EI Final Report Example

Attachment 4. Example of Prior EI Final Report

Health Consultation
Exposure Investigation
Blood Lead and Urine Arsenic Levels
ANACONDA CO. SMELTER
ANACONDA, MONTANA

October 17, 2019

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
Agency for Toxic Substances and Disease Registry
Division of Community Health Investigations
Atlanta, Georgia 30333

Health Consultation: A Note of Explanation

An ATSDR health consultation is a verbal or written response from ATSDR to a specific
request for information about health risks related to a specific site, a chemical release, or
the presence of hazardous material. In order to prevent or mitigate exposures, a health
consultation may lead to specific actions such as restricting use of or replacing water
supplies, intensifying environmental sampling, restricting site access, or removing the
contaminated material.
In addition, health consultations may recommend additional public health actions such as
conducting health surveillance activities to evaluate exposure or trends in adverse health
outcomes, conducting biological indicators of exposure studies to assess exposure, or
providing health education for health care providers and community members. This
concludes the health consultation process for this site, unless additional information is
obtained by ATSDR which, in the Agency’s opinion, indicates a need to revise or append
the conclusions previously issued.

You may contact ATSDR toll free at
1-800-CDC-INFO
or
visit our home page at: https://www.atsdr.cdc.gov

HEALTH CONSULTATION

Exposure Investigation
Blood Lead and Urine Arsenic Levels
ANACONDA CO. SMELTER
ANACONDA, MONTANA

Prepared by the
U.S. Department of Health and Human Services
Agency for Toxic Substances and Disease Registry
Division of Community Heath Investigations
Atlanta, Georgia 30333

Table of Contents
Executive Summary ........................................................................................................................ 2
1. Background and Purpose of the Exposure Investigation ........................................................ 7
1.1 Environmental Sampling Data.............................................................................................. 9
Residential Soils Overview..................................................................................................... 9
Recent Residential Yard Sampling ....................................................................................... 10
Dust in Attics and Home Interiors ........................................................................................ 10
Uncovered Waste in Place .................................................................................................... 10
1.2 Previous Biomonitoring...................................................................................................... 11
1.3 Risk Factors for Lead Exposure in Anaconda .................................................................... 13
1.4 Community Concern in Anaconda ..................................................................................... 13
2.0 Agency Roles .......................................................................................................................... 14
3.0 Methods................................................................................................................................... 16
3.1 Criteria for Participation ..................................................................................................... 16
3.2 Participant Recruitment ...................................................................................................... 17
3.3 Biologic Sample Collection and Analytic Procedures........................................................ 18
Blood Collection ................................................................................................................... 19
Urine Collection.................................................................................................................... 19
Statistical Methods................................................................................................................ 20
4.0 Results..................................................................................................................................... 20
4.1 Participants in the Exposure Investigation.......................................................................... 20
4.2 Evaluation of Exposure Investigation Results .................................................................... 22
4.3 Blood Lead Levels .............................................................................................................. 22
Lead and Health Effects........................................................................................................ 22
Blood Lead Results ............................................................................................................... 24
4.4 Urinary Arsenic Levels ....................................................................................................... 26
Arsenic and Health Effects ................................................................................................... 26
Urine Arsenic Results ........................................................................................................... 27
4.5 Correlation of Blood Lead and Urinary Arsenic Levels..................................................... 32
5.0 Limitations of this Exposure Investigation ............................................................................. 33
6.0 EI Conclusions ........................................................................................................................ 33
7.0 EI Recommendations .............................................................................................................. 34
8.0 Public Health Action Plan....................................................................................................... 35
8.1 Actions Completed ............................................................................................................. 35
8.2 On-going Actions................................................................................................................ 35
8.3 Actions Proposed ................................................................................................................ 36
9.0 References............................................................................................................................... 37
Appendix A: Anaconda Deer Lodge County Map and Demographics ........................................ 43
Appendix B: Summary of Cancer Incidence in Anaconda Deer Lodge County .......................... 44
Appendix C: Demographic and 2010 Census Information........................................................... 45
i

Appendix D: PESHU Recommendations for Lead...................................................................... 48
Appendix E: Analysis of Blood Lead and Total Urinary Arsenic Levels for Anaconda
Participants.................................................................................................................................... 51

Figures
Figure 1: Anaconda Smelter NPL Site (Montana): Site Location Map
Figure 2: Anaconda Smelter NPL Site (Montana): Site Features Map
Figure 3: Anaconda Blood Lead Levels Compared to NHANES
Figure 4: Boxplots of Anaconda blood lead levels compared to NHANES
Figure 5: Anaconda Urinary Total Arsenic Compared to NHANES
Figure 6: Anaconda Urinary Inorganic Arsenic Compared to NHANES
Figure 7: Boxplots of Anaconda urinary organic arsenic compared to NHANES
Figure 8: Boxplots of Anaconda urinary inorganic arsenic compared to NHANES

Tables
Table 1: Past (1977-1997) Biomonitoring Events in Anaconda
Table 2. Biomonitoring Result By Age [ARCO 2014]
Table 3: Exposure Investigation Activities and Agency Roles
Table 4: Goals, Recruitment Efforts and Participants for the Anaconda EI
Table 5: Summary of Participants by Age
Table 6: NHANES Levels Used for Urinary Arsenic Comparison for Individual Results

ii

Abbreviations and Acronyms
AAP
ADLC HC
AICc
ARCO
ATSDR
BLL
CDC
CI
Cr
CSEM
DHHS
DLS
DMA
EI
EPA
HD
IRB
µg/dL
µg/g Cr
ml
MMA
MTDPHHS
mg/kg
NIOSH
NCEH
NHANES
NPL
NTP
OMB
OU
PPE
PRA
RDU
RI/FS
ROD
UAS3
UAS5
UASB
UASC
UTMO
WIC

American Academy of Pediatrics
Anaconda Deer Lodge County Health Department
2nd order Akaike Information Criterion
Atlantic Richfield Corporation
Agency for Toxic Substances and Disease Registry
Blood Lead Level
Centers for Disease Control and Prevention
Confidence Interval
Creatinine
Case Studies in Environmental Medicine
Department of Health and Human Services
Division of Laboratory Sciences
Dimethylarsinic acid
Exposure Investigation
(U.S.) Environmental Protection Agency
Health Department
Institutional Review Board
micrograms per deciliter
micrograms per gram of creatinine
milliliters
Monomethylarsonic acid
Montana Department of Public Health and Human Services
milligrams per kilogram
National Institute for Occupational Safety and Health
National Center for Environmental Health
National Health and Nutrition Examination Survey
National Priorities List
National Toxicology Program
Office of Management and Budget
Operating Unit
Personal Protective Equipment
Paperwork Reduction Act
Remedial Design Unit
Remedial Investigation/Feasibility Study
Record of Decision
arsenous (III)
arsenic (V) acid
arsenobetaine
arsenocholine
trimethylarsine oxide
Women, Infants, and Children

Executive Summary
In the fall of 2018, the Agency for Toxic Substances and Disease Registry (ATSDR), in
coordination with the Montana Department of Public Health and Human Services (MT DPHHS),
conducted an Exposure Investigation (EI) in Anaconda, Montana to assess lead and arsenic
exposure. ATSDR tested a total of 367 people during two sampling events in September and
November of 2018.
Anaconda is home to the Anaconda Smelter Superfund Site, which the U.S. Environmental
Protection Agency (EPA) placed on the National Priority List (NPL) in 1983. Smelting
operations occurred in Anaconda from 1884 to 1977, resulting in contamination of soils in the
community. Soils contain elevated levels of lead and arsenic from the deposition of particulate
from stack emissions and the disposition of slag. Some attics have accumulated contaminated
dust. Under EPA oversight, the Potentially Responsible Party (PRP), Atlantic Richfield
Corporation (ARCO), has conducted extensive remediation; however, the residential soil cleanup is ongoing, and slag piles covering over a hundred acres remain uncovered. Anaconda also
has a significant number of older homes that may contain lead paint. As a result, the potential for
exposure to lead and arsenic in the community remains.
During ATSDR-sponsored community meetings held in 2018, Anaconda citizens and local
officials expressed a need for better understanding of current exposures to site contaminants. In
response, ATSDR committed to an exposure investigation in Anaconda, including the
community of Opportunity within the Anaconda municipality.
In August 2018, ATSDR invited all residents of Anaconda to participate in biological testing to
evaluate potential exposure in the community. An invitational mailing, local media, and
Anaconda social media publicized the event. Outreach also included providing health education
on lead and arsenic to local physicians, daycares, and schools. The Anaconda Deer Lodge
County Health Department (ADLC HD) posted flyers detailing the testing event at key locations
around the community.
The ATSDR EI team collected blood (lead) and urine (arsenic) samples from participants living
within the Anaconda community. Although all members of the community were invited to
participate in the EI, the populations most vulnerable to the effects of lead include young
children with hand-to-mouth behavior (especially children with pica behavior) and women who
are pregnant or of childbearing age.
ATSDR tested 191 participants in September. Community interest was high, and approximately
150 residents were placed on a wait list. ATSDR tested 177 people in November 2018 to
accommodate the wait-listed residents. For the November event, ATSDR reached out to Head
Start and Anaconda preschools and elementary schools to recruit additional young children and
women of childbearing age. The total sample population of 367 people over both events (one
person was tested in both events).
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Within 12 weeks of testing, ATSDR provided result letters to every participant and the
opportunity to contact an ATSDR Medical Officer and/or ATSDR staff. ATSDR’s Medical
Officer called the few individuals with results near or above ATSDR levels of concern for either
lead or arsenic. Results letters provided recommendations for reducing exposure to lead and
arsenic both inside and outside the home regardless of testing results. Outreach and testing
events increased awareness of lead and arsenic exposure prevention, especially awareness of nocost programs available to residents that test residential soils and attic dust for contaminants.
Evaluation of Exposure Investigation Results
ATSDR adopted the Center for Disease Control and Prevention (CDC) blood lead reference
value of 5 micrograms per deciliter (µg/dL) to identify children with blood lead levels (BLL) that
are higher than most children’s levels [CDC 2012 a,b,c]. CDC and the American Academy of
Pediatrics (AAP) recommend case management to reduce BLL for children above the 5 µg/dL
level of concern [CDC 2012 a,b,c, AAP 2016]. The CDC reference value is based on the 97.5th
percentile blood lead distribution in children aged 1 to 5 years from data collected in the National
Health and Nutritional Examination Survey (NHANES) from 2007 to 2010 [CDC 2012 a,b,c]. In
2015, the National Institute for Occupational Safety and Health (NIOSH) designated 5 µg/dL as
the reference blood lead level for adults in the workplace [NIOSH 2015].
Different species of arsenic are present in food, water, and the human body, and the EI
laboratory analysis distinguished these various forms in urine. The source and toxicology of
organic arsenic differs from inorganic arsenic. To identify elevated levels of urinary arsenic
ATSDR adopted the 95th percentile of the most recent NHANES values as a benchmark for total,
organic and inorganic urinary arsenic. Following the NHANES methodology, we summed the
four inorganic arsenic species (measured in NHANES) evaluated in the EI to permit comparison
of the EI data set to NHANES.
The age distribution of Anaconda EI participants differed from the age distribution of the 20152016 NHANES study group. To ensure a relevant comparison of median values, we developed
an age-adjusted NHANES median based on accepted statistical methods. The median offers
insight into exposures to the community. The median (50th percentile) of the Anaconda
aggregated data for BLL and urinary arsenic were compared to the age-adjusted median
NHANES levels. In addition, we compared results to the expected 5th, 50th and 95th percentiles of
NHANES by age.
An EI captures an exposure “snapshot in time.” EI results are limited since they are only
applicable to the individuals tested and cannot be generalized. EI results do not tell us when the
exposure occurred or the specific source of exposure.

3

Blood Lead Testing Findings
There is no identified threshold or “safe” blood lead level, and some studies indicate that even
very low BLLs can cause neurological, cognitive, and attention-related behavioral issues in
children [CDC 2012b]. Although CDC adopted the 5 µg/dL reference value to identify elevated
BLL in children aged 1 to 5 years old, ATSDR, along with the MT DPHHS and the ADLC HC,
uses this value as the follow-up level for lead for participants of all ages in this investigation.
All 18 children younger than 6 years old who participated in the testing events measured a BLL
< 5 µg/dL. Similarly, all 54 children ages 6-19 who were tested had BLL values < 5 µg/dL.
Three of 295 adults (i.e., ages 20 and above) tested had BLL ≥ 5µg/dL (maximum of 9.14
µg/dL). The three with BLL ≥ 5µg/dL ranged in age from 58 to 72.
Aggregate Anaconda BLLs were also compared to the representative median value found in
blood in the U.S. population [CDC 2019a; 2015-2016 data set] and the expected 5th, 50th and 95th
percentiles of NHANES by age. ATSDR used poststratification to match the age characteristics
of the Anaconda EI group (which was generally older), as age is an important predictor of BLL.
All participants tested had measurable lead in the blood (level of detection = 0.07 µg/dL).
Anaconda residents had a median BLL of 1.1 µg/dL which was slightly higher than the ageadjusted median BLL in NHANES of 0.95 µg/dL (difference of 0.15 µg/dL). The difference is
statistically significant but not clinically significant; no difference in clinical health effect would
be discernable between these two values. In general, the BLL values measured in the Anaconda
community in this EI are comparable to national values reported in the 2015-2016 NHANES
[CDC 2019a].
The results of the questionnaire provided insight into potential sources of blood lead in the
participants. Linear mixed effects modeling revealed that being older, being a male, entering the
attic more frequently than once per month, and self-reported occupational exposure to lead were
associated with higher BLL.
Urine Arsenic Testing Findings
The various forms of arsenic found in the human body can be categorized as organic and
inorganic. Organic forms of arsenic are associated primarily with diet, especially seafood;
inorganic forms are generally associated with environmental exposures [ATSDR 2007c, Schoof
1999]. Inorganic arsenic is associated with industrial contamination and may enter the food chain
becoming a source of dietary inorganic arsenic. For the Anaconda EI, ATSDR measured total
arsenic in urine, and speciation was performed to determine the relative organic and inorganic
portions. ATSDR compared levels of total arsenic, inorganic arsenic and organic arsenic in urine
samples for individual participants to the age-specific 95th percentile for the U.S. population
reported in NHANES. We compared the median urinary arsenic values for the aggregate EI data
to the representative median value in NHANES. Inorganic urinary arsenic was evaluated as the
sum of four inorganic arsenic species. The results of the questionnaire were used to better
4

understand how people may have been exposed to arsenic.
Testing results for urinary inorganic arsenic in one participant from the September testing (age
58) and two participants from the November testing (age 3 and 74) were above the age-specific
95th percentile of NHANES. The three participants were called by the EI Medical Officer to
discuss their elevated results and provide recommendations to reduce exposure.
For Anaconda EI participants, the median urinary total arsenic of 6.7 micrograms per gram of
creatinine (µg/g Cr) was 0.9 µg/g Cr higher than the age-adjusted NHANES median of 5.8 µg/g
Cr. The median urinary total inorganic arsenic level of 4.6 µg/g Cr was 0.2 µg/g Cr lower than
the age-adjusted NHANES median of 4.8 µg/g Cr [CDC 2019a]. Higher urinary organic arsenic
in Anaconda EI participants compared to NHANES accounts for the difference in total urinary
arsenic in the two sample populations. An evaluation of the questionnaire provides evidence for
why this was found. EI participants with elevated organic arsenic had eaten food known to
contain organic arsenic (e.g., seafood, chicken) in the week preceding the testing. Organic
arsenic is not harmful to humans at these levels.
The results of the questionnaire provided insight into potential sources of total urinary arsenic in
the participants. Linear mixed effects modeling revealed that entering the attic more frequently
than once per month and eating seafood were associated with higher total urinary arsenic levels.
EI Conclusions
•

•
•
•

•

The overall conclusion of the EI is that levels of blood lead and urinary arsenic measured
in residents of Anaconda that participated in the EI are comparable to the U.S.
population, as reported in NHANES.
All 18 children younger than 6 years old who participated in the testing events measured
a BLL below the 5 µg/dL follow-up level.
The median BLL for all EI participants was approximately 0.15 µg/dL higher than the
U.S. median, but this difference is not clinically significant.
For arsenic, Anaconda EI participants had a slight elevation in total urinary arsenic
(approximately 0.9 µg/gm Cr higher) compared to NHANES participants. The elevation
in total arsenic, however, appears to be attributable to organic arsenic given that the level
of inorganic arsenic was slightly lower (0.2 µg/gm Cr) than comparable NHANES
values. Organic arsenic enters the body through diet and is not toxic at these levels. The
organic arsenic testing results correlated to participants who reported eating foods high in
organic arsenic. ATSDR would not anticipate health effects associated with urine arsenic
levels measured in the Anaconda participants.
Evaluation of the questionnaire administered at the time of the testing suggests that
people can take measures to further reduce their exposure to lead. The analysis of
questionnaire data in relation to BLL indicates that people who reported working in
construction and maintenance jobs had higher BLLs.
5

•

•

Many Anaconda attics are contaminated with lead and arsenic as a result of smelter
activities in the past. Participants who reported entering their attics on a regular basis
generally had higher BLL and total arsenic than other participants.
The EI results do not mean that the risk of exposure to lead and arsenic in Anaconda
has been eliminated; residents should continue to be proactive in preventing exposure.

EI Recommendations
ATSDR identified specific actions, consistent with prudent public health practice that may
further reduce the risk of lead and arsenic exposures in Anaconda residents. ATSDR
recommends primary prevention efforts to avoid exposure to lead and arsenic in soil. ATSDR
supports the following recommendations and public health actions.
•

•

Anaconda citizens (including landlords) should participate in the Superfund Community
Soils OU residential yard and attic clean-up programs as a primary mechanism for
reducing potential exposure to lead and arsenic. Through the Superfund program (funded
by ARCO with EPA oversight), residents may opt for soil and attic testing. Based on the
results, residents can qualify for a contractor to clean contaminated attics. EPA and
ADLC should make efforts to increase participation in these programs. In the meantime,
ATSDR recommends that residents minimize time (or seal entryway) in untested or
contaminated (but not yet remediated) attics.
Anaconda citizens should take prudent actions to avoid contact with potentially
contaminated soil. These actions include:
o Avoid areas of known contamination (e.g., slag piles) and instruct children not to
play or ride bikes there;
o Supervise children closely to modify or eliminate risky hand-to-mouth behaviors
or intentional eating of dirt (pica behavior);
o Damp mop and damp dust surfaces;
o Cover bare soils with vegetation (grass, mulch, etc.) and create safe play areas for
children with clean ground cover;
o Remove shoes before entering the home;
o Bathe pets regularly to avoid them tracking contaminated soil into homes.

•

•

•

Anaconda citizens should take precautions to prevent exposure to lead from lead paint
during house renovations in homes build prior to 1978. Information is available at:
https://www.epa.gov/lead/protect-your-family-lead-your-home.
The EPA and ARCO should minimize risk of exposure to lead and arsenic from
uncovered slag through improved signage (specifically uncapped slag piles) and
Superfund remedial actions.
The ALDC Health Department should conduct regular BLL screenings for children under
age 6 based on risk identified from site contamination and the AAP recommendation
[AAP, 2016] of regular BLL screenings for communities with a significant portion of
6

•

•

homes built before 1960. Ensure venous draws and physician follow-up for capillary
BLL at or above the CDC Reference value of 5 µg/dL.
Primary healthcare providers should continue to improve understanding of lead screening
and ways to reduce exposure to site contaminants and lead paint. ATSDR’s Case Studies
in Environmental Medicine (CSEM) provide a self-instructional primer. The lead and
arsenic CSEMs are available at:
https://www.atsdr.cdc.gov/csem/csem.asp?csem=34&po=0
https://www.atsdr.cdc.gov/csem/csem.asp?csem=1&po=0
People working in jobs where lead and arsenic are present should use appropriate
personal protective equipment (PPE) while on the job to reduce exposure. Regular hand
washing and removing outer garments before entering the home after work reduces
exposures and protects family members.

1. Background and Purpose of the Exposure Investigation
Anaconda is the county seat of Anaconda-Deer Lodge County (a consolidated city-county
government) (ADLC) and is located at the southern end of the Deer Lodge Valley in
southwestern Montana (Figure 1). Figure 1 provides the location of the Anaconda Smelter
Superfund site in relation to other sites in the vicinity. The Anaconda Smelter Superfund Site
covers approximately 300 square miles of land impacted by smelter operations and ore
processing wastes. The site includes both Anaconda and the community of Opportunity located
within the municipality of Anaconda (Figure 2). Smelting operations over a 100-year history led
to an estimated 260 million cubic yard deposition of heavy metals from mill tailings, furnace
slag, and flue dust [EPA 1996]. Over 20,000 acres of soils (both residential and commercial)
were contaminated by emissions [EPA 2015].
In the 2010 census, the population of ADLC was 9,139 with 28% of the population living with
an income below the poverty level (Appendix A). Lead exposure may also result from lead in
house paint since 80% of the homes in Anaconda were built before 1980, when lead was allowed
in house paint (Appendix A). Homes built before 1960 are more likely to contain lead paint
[DHHS, 2011], and approximately 55% Anaconda homes were built before 1960 [Census
Bureau 2013-2017]. Older homes in this area may have copper water pipes joined with leaded
solder. Testing of tap water in nearby Butte in 1994 indicated that lead leaching from older
plumbing may be a source of lead exposure [EPA, 1994].

7

8

1.1 Environmental Sampling Data
ARCO, under EPA oversight, has conducted extensive environmental sampling over the course
of the site’s Superfund history. The information presented here provides an overview of historic
sampling followed by recent data that informs our understanding of present exposure pathways.
EPA often portions a site into smaller units, or Operable Unit (OU), to assist in site management
and ultimate cleanup of a site.
Residential Soils Overview
Through the Superfund process, ARCO and EPA together completed approximately 21 soil
investigations between 1985 and 1995. Analytic results from the 1997-1998 Remedial
Investigation/Feasibility Study (RI/FS) established the Community Soils OU as the focus of
residential clean ups. This OU includes residential yards in Anaconda, Opportunity, and rural
areas in the Anaconda vicinity. This focus area of remediation encompasses the population at
greatest current risk for exposure to arsenic and lead. Though ARCO has completed many
9

remedial activities for residential soils, EPA’s Fifth Five Year Review Report in 2015 [EPA
2015] concluded “the remedy for the Community Soils OU is not protective because exposure to
… contamination in residential soil and dust is not currently controlled.”
In 2006, ARCO sampled over 1,400 residential yards in Anaconda and the surrounding rural area
[EPA 2008]. Of these, 300 yards exceeded the 250 mg/kg action level for arsenic. Analysis of
the sampling indicated that arsenic contamination was more widespread than indicated in
previous decision documents. Also in 2006, ARCO evaluated residual lead concentrations in
yards where arsenic concentrations measured below the 250 mg/kg cleanup benchmark. The
results indicated that lead concentrations in residential soils posed a significant exposure
pathway for lead even where the arsenic level was below 250 mg/kg [EPA 2008]. A total of 347
of 554 soil samples exceeded the EPA 400 mg/kg lead clean up benchmark [EPA 2008]. The
lead and arsenic in community soils do not appear to be correlated; the reason is not known but
may be associated with differing deposition of lead and arsenic when the smelter was in
operation.
Recent Residential Yard Sampling
Remediation actions continued from 2015 to 2017 for the Community Soils OU with the action
levels set at 250 mg/kg and 400 mg/kg for arsenic and lead, respectively. Data collected in 2015
and 2016 data confirmed continued risk for community exposure to lead and arsenic through
residential soil [ATSDR 2018].
Dust in Attics and Home Interiors
The higher than anticipated soil arsenic concentrations prompted ARCO to sample attic dust for
arsenic and lead in 52 homes [ARCO 2008]. Environmental sampling of attic dust has
established that historic smelter emissions settled in home attics. In its analysis of the correlation
of contaminant levels found in residential interior, exterior, and attic dust, EPA concluded that
“attic dust may be a secondary source of interior dust arsenic and lead contamination” [EPA
2008]. In 49 attics sampled, the mean arsenic and lead values (496 mg/kg and 721 mg/kg,
respectively) were above the remedial action levels for soils [ARCO 2008].
The Community Soils Record of Decision [EPA 2013] established an attic remediation program
for residences located in the Community Soils OU. Testing and remediation of attic dust is an
ongoing process, though initial results indicate that approximately half of sampled attics require
remediation. Attic dust is a current pathway of exposure to lead and arsenic.
Uncovered Waste in Place
EPA’s most recent Superfund Five-Year Review identified areas with uncovered wastes left in
place. The remedy included some slag piles intentionally left in place for historic preservation
recognizing Anaconda’s history in processing copper ore [EPA 2015]. Some of these areas are
10

accessible to trespassers resulting in potential exposures through inhalation of airborne
particulates and contact with contaminated soils near the pile.
An area known as the Old Works Historic District, located in the Old Works/East Anaconda
Development Area Operating Unit, contains ore processing waste from smelter operations dating
from 1884-1902. In 2010, EPA estimated that 60,000 to 75,000 cubic yards of contaminated
waste remained [EPA 2015]. Previous sampling has indicated that portions of this waste exceed
the 1,000 mg/kg remedial action level for arsenic established for recreational/open
space/agricultural areas [EPA 2015].
Substantial progress in remediation has been made in the Anaconda Regional Water, Waste, and
Soil Operating Unit; however, remediation is not complete for multiple remedial design units
(RDUs) covering thousands of acres of contaminated land located within this OU. Three slag
piles covering approximately 197 acres and consisting of approximately 25.5 million cubic yards
of smelter slag are located within this OU. Wind and erosion control measures are in place;
however, particulates are entrained in air during high wind events [EPA 2015].
1.2 Previous Biomonitoring
In the past, several biomonitoring investigations have been conducted evaluating potential
exposure to residents exposed to environmental contaminants from smelting activities. The
ATSDR Health Consultation [ATSDR 2007a] provides information on the past biomonitoring
events in the Anaconda area; they are summarized in Table 1.

11

Table 1. Past (1977-1997) Arsenic Biomonitoring Events in Anaconda*
Reference
Testing
Conclusion
Baker et al.
Arsenic in hair and
Nationwide survey of children living around copper,
1977
urine
lead or zinc smelters, including Anaconda.
• Both hair and urine arsenic levels (total) in
Anaconda were above levels found in
comparison towns without smelters.
Hartwell et al. Arsenic in hair,
Nationwide survey of children living around copper,
1983 (testing
blood and urine
lead or zinc smelters, including Anaconda.
completed
(also evaluated air,
• Dust arsenic levels correlated best with hair
from 1978soil, dust, and tap
arsenic levels for all age groups; urine arsenic
1979)
water)
(total) correlated with air, water and dust
arsenic levels for 1 to 5 year old children.
Anaconda Smelter closed in 1980
Binder et al.
Arsenic urine (total) Four locations were evaluated and compared to each
1987 (testing
(also soil and house other. In the Mill Creek neighborhood (downwind of
completed in
dust)
smelter and adjacent to the stack): higher mean arsenic
1985)
in soil and urinary arsenic in children vs Eastern
Anaconda (upwind of stack), Opportunity (4 miles
downwind of smelter) and the control town. Eight
children relocated from Mill Creek based on this
investigation.
Hwang et al.
1997 (testing
completed in
1992-1993)

Total and speciated
arsenic in children
in Anaconda

Speciated urine arsenic concentration correlated with
soil arsenic level in bare yards.

* ATSDR (2007a)

In 2013, ARCO contracted with ENVIRON International Corporation in consultation with
ADLC HD to conduct a baseline blood lead and urinary arsenic biomonitoring study to evaluate
potential exposures of residents in the Anaconda area. Blood lead levels (BLL) and urine arsenic
sampling was offered to community members and results are presented in Table 2 [ARCO 2014].

12

Table 2: Biomonitoring Results by Age [ARCO 2014]
Blood Lead Levels

Number detections (DL = 1.0
µg/dL) /number tested
Concentration range (µg/dL)

Total Arsenic (µg/L)
Speciated Arsenic (µg/L) *
Speciated Arsenic, Specific
Gravity-Corrected (µg/L)
Speciated Arsenic, CreatinineCorrected (µg/g)

≥ 7 years
26/84

< 7 years
7/18
1-3.8
Urine Arsenic Results
<12 years
Number of Concentration
participants
Range of
detections
32
4.24-39.5
32
4.61-25.4
29
4.56-22.5
30

4.69-33.4

1-5.4
≥12 years
Number of Concentration
Participants
Range of
Detections
74
1.36-363
74
1.15-90.6
61
1.87-77.5
66

1.83-63.7

* Combined inorganic species, arsenous (III) acid and arsenic (V) acid, and their methylated metabolites
[monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA)] results.
DL = Detection Limit

1.3 Risk Factors for Lead Exposure in Anaconda
In addition to the potential exposure to contaminated soil, people living in the area have multiple
factors associated with increased risk of lead exposure. The census tract has a large percentage of
homes built before 1980 (80%) that may have lead-based paint and lead pipes that may impact
drinking water [Census Bureau 2010] (Appendix A). In addition, approximately 28% of residents
in Anaconda were below the poverty line in 2015 [American Fact Finder 2018] (Appendix A).
Poverty is an additional risk factor for increased BLL [Dixon et al. 2009, Jones et al. 2009,
Bernard et al. 2003].
1.4 Community Concern in Anaconda
In community meetings held in 2018, Anaconda citizens and local officials expressed a need for
a better understanding of current exposures to site contaminants. One of the outcomes of the
meetings was the identification of the need to conduct biomonitoring for lead and arsenic in the
community as a result of long-term exposure to products of the smelting process.

13

The MT DPHHS provided a summary of cancer incidence in ADLC (Appendix B). The results
of the analysis indicated that the rate of new cancer cases remains the same among ADLC
residents when compared to all Montana residents, and cancer in ADLC is not occurring at rates
higher than the rest of Montana.

2.0 Agency Roles
Many activities are conducted during an EI. ATSDR, the lead agency for the EI, collaborated
with EPA, the Montana Department of Public Health and Human Services (MT DPHHS), the
Anaconda Deer Lodge County Health Department (ADLC HD), and the CDC National Center
for Environmental Health (NCEH) Division of Laboratory Sciences (DLS) to complete these
activities. The roles of each agency are described in Table 3.

14

Table 3. Exposure Investigation Activities and Agency Roles
Activity
EI protocol and
PRA/OMB submittal

Agency
ATSDR

Agency Role
Completed the EI protocol which included Fact
Sheets, Flyers, Posters, Questionnaire, Parental
Permission, Consent and Assent Forms,
Sampling and Analysis Plan
Submitted the Paperwork Reduction Act (PRA)
forms to the Office of Management and Budget
(OMB) for approval to administer the
questionnaire and consent forms. This package
also included an Institutional Review Board
(IRB) exemption since the EI is not considered
to be research.

Identification of area
with risk for lead and
arsenic exposure

EPA, ADLC HD,
ATDSR

Provided information regarding soil lead levels
and the status of remediation in the Community
Soils OU to identify a mailing list for
recruitment materials.

Provided ATSDR
with BLL for
Anaconda Residents

EPA and MT
DPHHS

Both agencies provided ATSDR with historical
BLL data for children in Anaconda. The
agencies continue to engage the community
regarding potential lead contamination in
Anaconda.

Participant
recruitment

ATSDR, ADLC
HD

Sent informational postcards, and scheduled
appointments.

Blood sample
collection

ATSDR, MT
DPHHS, ADLC
HD, DLS

Administered parental permission/assent/consent
forms to participants and their parent/guardian.

NCEH/DLS

Used approved laboratory methods to analyze
biological samples for lead and arsenic. Provided
results to ATSDR.

Blood and urine
sample analysis

Hired or provided licensed phlebotomists to
draw blood from participants.

15

Table 3. Exposure Investigation Activities and Agency Roles
Activity
Reporting of results

Agency
ATSDR, MT
DPHHS, ADLC
HD

Agency Role
Prepared and mailed letters with results to all
participants.
Contacted EI participants who had BLL ≥ 5
µg/dL to recommend follow-up with their
physician.
Contacted EI participants with inorganic arsenic
levels greater than NHANES to discuss reducing
exposure to arsenic.
Evaluated data and prepared the Exposure
Investigation (EI) report.

Abbreviations: ATSDR, Agency for Toxic Substances and Disease Registry; EPA, Environmental Protection
Agency; MT DPHHS, Montana Department of Public Health and Human Service; ALDC HD, Anaconda Deer
Lodge County Health Department; NCEH/DLS, National Center for Environmental Health/Division of
Laboratory Services

3.0 Methods
The goal of the EI was to implement sample collection in September 2018 when contact with soil
(and therefore exposure to arsenic and lead) was expected to be high due to increased outdoor
activity by residents. Exposure to soil is expected to be highest during months with good
weather. Given high community participation, an additional round of testing was completed in
November 2018.
3.1 Criteria for Participation
All members of the Anaconda municipality, including those living in the Opportunity
community, were eligible to be included in the Exposure Investigation (EI). The EI was initially
conducted to test up to 200 persons in the Anaconda community (September 2018). The first
effort was very successful (191 participants), and an additional 150 people were put on a waiting
list for a second round of testing. For the second round of testing (November 2018), testing was
offered to those on the waiting list and others who approached the ADLC HD to ask about
testing. In addition, given the low number of young children and women of childbearing age that
were tested in September, outreach to Head Start and the preschools/elementary schools in
Anaconda was conducted to recruit participants from these groups. Young children (younger
than 6 years old) and women who are pregnant or of childbearing age are most susceptible to the
effects of elevated BLL.

16

3.2 Participant Recruitment
Table 4 provides the goals, recruitment strategy and participant profile for the two testing events.

Table 4: Goals, Recruitment Efforts and Participants for the Anaconda EI
Testing Event
September 14-17, 2018

November 3-6, 2018
Goal

Given community concern, all members of
the Anaconda community were invited to
participate.

Individuals who were on the waiting list after
the first testing round were offered testing. In
addition, young children and women of
childbearing age were specifically recruited.

Recruitment Effort
•
•

•

•

•

•

Invited all Anaconda residents to be
tested for BLL and urine arsenic
Mailed approximately 5000
recruitment postcards inviting
residents to be tested approximately 3
weeks prior to testing. Approximately
20% of the letters were returned as
undeliverable.
Provided and distributed fact sheets
and recruitment posters within the
community by ADLC HD and
ATSDR Region 8 personnel
Provided a Grand Rounds presentation
and information packets for lead and
arsenic information to local physicians
in Butte and Anaconda
Announced the testing event in a press
release in the local Anaconda
newspaper (Anaconda Leader and
Montana Standard)
Used local resources and contacts,
including the ADLC HD and the MT
DPHHS, to publicize the EI testing
event.

•
•
•

•

Invited all Anaconda residents that
were on the waiting list to participate
Recruited young children and women
of childbearing age to participate
Provided information to Head Start
and preschools and elementary
schools in the community to recruit
young children and women of
childbearing age
Used local resources and contacts,
including the ADLC HD and the MT
DPHHS, to publicize the EI testing
event.

17

Table 4: Goals, Recruitment Efforts and Participants for the Anaconda EI
Testing Event
September 14-17, 2018

November 3-6, 2018
Participants

•

•
•

191 participants
o 1 child younger than 3 yrs
o 2 children aged 3-5 yrs
o 12 children aged 6-11 yrs
o 13 children aged 12-19 yrs
o 163 adults aged 20 yrs and older
184 tested for blood lead†
185 tested for urine arsenic†

• 177 participants
o 5 children younger than 3 yrs
o 10 children aged 3-5 yrs
o 19 children aged 6-11 yrs
o 10 children aged 12-19 yrs
o 133 adults aged 20 yrs and older*
• 175 tested for blood lead†
• 173 tested for urine arsenic†

EI = Exposure Investigation; BLL = Blood Lead Level; ATSDR = Agency for Toxic Substances and Disease
Registry; ADLC HD = Anaconda Deer Lodge County Health Department; MT DPHHS = Montana Department of
Public Health and Human Services
* One adult participant was tested for BLL in both testing events
† Not all participants were tested for both lead and arsenic.

3.3 Biologic Sample Collection and Analytic Procedures
ATSDR completed the biological sample collection at the Anaconda Community Service Center,
located at 118 East 7th Street in Anaconda, from September 14-17, 2018 and November 3-6,
2018. We offered weekend and early evenings testing times for the convenience for Anaconda
residents.
Prior to the testing date, participants were asked to obtain a urine collection kit from the ADLC
HD. The urine collection kit included a urine collection cup and instructions on how to obtain a
first morning urine sample. Once the urine sample was collected, the participant was asked to put
it directly into their freezer and bring it with them to their blood collection appointment.
At the blood collection location, the participants signed in and provided their frozen urine sample
to ATSDR personnel, who logged it into a hard copy and electronic data collection log. To
maintain privacy, the samples were labeled with a unique identification number. No personal
information was sent to the laboratory. The EI team then administered the appropriate
Consent/Assent/Parental Permission form and OMB-approved questionnaire (OMB # 09230048) to each participant. The household questionnaire included questions on demographics,
characteristics and age of residences, and activities that might result in exposure to lead and
arsenic. Federal rules require that ATSDR maintain confidentiality of the information gathered
through interviews as well as the results of laboratory tests.

18

Blood Collection
After the consent forms were administered and the questionnaire completed, the participant
provided a blood sample for analysis. Licensed phlebotomists (medical professionals who draw
blood from a vein) were obtained from the MT DPHHS, DLS and from local sources.
Blood lead sampling is the most reliable method for measuring lead exposure from all sources
[Barbosa et al. 2005]. Whole blood samples were obtained by venous puncture. A phlebotomist
collected 3 milliliters (ml) of blood from each participant who provided consent. The collection
tubes and supplies were provided by the NCEH/DLS. As with the urine samples, the blood
samples were logged on a hard copy and electronic collection log and were labeled with a unique
identification number.
After collection, blood samples were maintained near 4ºC throughout the week and during
overnight shipment. Samples were delivered for analysis to the NCEH/DLS laboratory in
Atlanta, Georgia.
The NCEH/DLS laboratory performed blood lead testing in Atlanta, Georgia using NHANES
Method 2009-2010 [CDC 2009-2010] and Quality Assurance/Quality Control for lead according
to NHANES 2007-2008 [CDC 2007-2008a,b].
Urine Collection
Urine arsenic is the most reliable method for measuring arsenic exposures occurring within a few
days prior to the sample collection. A 24–hour urine collection is considered the optimal method
to collect urine for arsenic sampling due to fluctuations in excretion rates. However, most studies
use a first morning void or random spot sample because it is convenient for the participant and
improves their compliance. These methods appear to correlate well with 24-hour collection
results [Orloff et al. 2009, Hinwood et al. 2002]. Participants were provided a urine collection kit
that included the urine collection cups (provided by DLS for quality control) and instructions for
urine collection and freezing of the sample.
Frozen urine samples brought to the collection location were placed on dry ice and shipped
frozen by FedEx overnight to NCEH/DLS in Atlanta for analysis. DLS analyzed the urine for
total arsenic by DLS method 3031.1 and DLS method 3000.15-02 for speciated arsenic by high
performance liquid chromatography inductively coupled plasma dynamic reaction cell mass
spectrometry (HPLC ICP-DRC-MS).
All urine specimens were analyzed for total arsenic, speciated arsenic, creatinine and specific
gravity. Seven arsenic species were analyzed: three methylated metabolites (organic)
[arsenobetaine (UASB), arsenocholine (UASC) and trimethylarsine (UTMO)] and four inorganic
arsenic species [arsenic (V) acid (UAS5), arsenous (III) acid (UAS3), dimethylarsinic acid
(DMA) and monomethylarsonic acid (MMA)]. The urine test results were creatinine-corrected,
19

as age appropriate. The organic arsenic species were evaluated individually while the four
inorganic arsenic species were summed and evaluated as a total inorganic arsenic value. To
maintain privacy, the samples were labeled with a coded identification number so no personally
identifiable information was provided to the laboratory.
Statistical Methods
Results for lead, total creatinine corrected urinary arsenic, and inorganic creatinine corrected
urinary arsenic were compared to NHANES 2015 – 2016 [CDC 2019a] after post stratification to
adjust for differences in ages between the NHANES 2015 – 2016 population and the Anaconda
EI participants. Similarly, organic creatinine corrected urinary arsenic results were compared to
post stratified NHANES 2015-2016 data for UASB and UASC; UTMO was evaluated using data
from the 2011-2012 NHANES data set since that was the last year UTMO was evaluated [CDC
2019a].
We assigned the limit of detection divided by the square root of two for results less than the limit
of detection for inorganic arsenic results, consistent with the approach taken in NHANES. We
calculated 50th and 95th percentiles for the age-adjusted NHANES and betaWald 95% confidence
intervals using R software package [Lunley 2019, R Core Team 2019]. To compare how the
Anaconda EI participants compared to the U.S. population, we compared boxplots for the
Anaconda EI results to the age-adjusted 2015-2016 NHANES. In addition, we compared results
to the expected 5th, 50th and 95th percentiles of NHANES by age.
For the EI participants, one participant gave biological samples in both the September and
November events, so the results were averaged. To compare the NHANES results to the
Anaconda EI participants, we developed boxplots and calculated median estimates of blood lead
and urinary arsenic and calculated bootstrap 95% percentile confidence intervals (1,999
replications) for these parameters [Manly 2007]. We also compared the logs of blood lead to the
logs of urinary total and inorganic arsenic levels using Pearson’s correlation coefficient.
Anaconda results were evaluated using linear mixed effects modeling. Further details are
discussed in Appendix E.

4.0 Results
4.1 Participants in the Exposure Investigation
There were 367 participants in the Anaconda EI: 191 participants in the September testing event
and 177 participants in the November testing event (one participant was tested in both the
September and November testing event for BLL). Table 5 below presents the break down by age
as reported by participants.

20

Table 5. Summary of Participants by Age
Total number of participants tested
Age Group
September

November

Total

Less than 3 years
3 to 5 years old
6 to 11 years old
12 to 19 years old
≥ 20 years old

1
2
12
13
163

5
10
19
10
133

6
12
31
23
295*

TOTAL

191†

177ǂ

367

* one participant was tested in both the September and November sampling round for BLL
†
184 were tested for blood lead and 185 were tested for urine arsenic
ǂ
175 were tested for blood lead and 173 were tested for urine arsenic

The demographics of the sampled population and the demographics of the community based on
the 2010 US Census is presented in Appendix C. The table in Appendix C presents the
demographic data for each testing event as well as a summation for both efforts. The results
indicate that the demographics were similar between testing events and were consistent with the
results from the 2010 Census.
Based on information gathered from the questionnaire, the majority of the homes in the
community are single-family homes (93%) with most being built prior to 1980 (77 to 85%).
Lead paint, a risk factor for children for lead exposure, ceased being manufactured in 1978, so
homes built prior to 1980 may contain lead paint.
The most sensitive population groups associated with the potential impacts of lead exposure are
young children (younger than 6 years) and pregnant women or women of childbearing age. For
the second round of testing in November 2018, ATSDR recruited additional participants in these
groups. ATSDR tested 18 children younger than 6 years old in the EI, which represents
approximately 5% of the population tested during the EI (18/367 participants tested). The
percentage of children younger than 6 years old tested in the EI is comparable to the percentage
of children in this age group identified in the 2010 Census (348/9,139 residents; approximately
4%) [Appendix C].
There were a greater number of male children (63%) than female children (38%) tested and a
greater number of female adults (57%) than male adults (43%) tested. Close to 100% of those
tested identified as white (97%) and few identified as being of Mexican descent (2 to 7%). These
results are comparable to the results from the 2010 census (93% white and 3% of Mexican
descent) [Appendix B].
21

The questionnaire results indicate that the community is stable with 75% of adults living in their
home for 10 years or longer. Approximately 27% of participants indicated that the soil in their
yards had been replaced by EPA, indicating that the lead or arsenic levels in their yard soil
warranted cleanup in the past but only 10% have had their attics professionally cleaned
[Appendix C].
Questions associated with resident’s lifestyle included questions about occupational exposure,
whether participants remove their shoes prior to entering their home and questions about their
diet to provide context for arsenic exposure. Approximately 24% of participants lived in a home
where a family member worked in a profession associated with potential exposure, such as
construction work. About half of the participants never or seldom take off their shoes before
entering their home, thereby tracking in soil that may become dust in the home. It was clear that
many participants consumed food items that are associated with potential exposure to arsenic,
including seafood (36%), rice (45%) and chicken (83%) [Appendix C].
4.2 Evaluation of Exposure Investigation Results
The CDC assesses the health and nutritional status of adults and children in the general U.S.
population through the National Health and Nutritional Examination Survey (NHANES).
NHANES evaluates health and nutritional status by applying a survey that includes interviews
and physical examinations in people across the U.S. The testing of BLL and urinary arsenic is
included in NHANES: data from the 2015-2016 testing events were used to evaluate BLL and all
urinary arsenic species except for UTMO, which was evaluated using the 2011-2012 data set
because NHANES did not test for urinary UTMO after 2012 [CDC 2019a].
For the Anaconda EI, ATSDR used the CDC blood lead reference value of 5 micrograms per
deciliter (µg/dL) to identify children who require case management [CDC 2012a]. The CDC
reference value is based on the 97.5th percentile of the NHANES’s 2012 blood lead distribution
in children aged 1 to 5 years [CDC 2019a]. Each participant’s BLL was compared to the
reference value of 5 µg/dL and reported directly to the participant. Similarly, the arsenic results
(total and speciated) for each participant were compared to the 95th percentile of the NHANES
for each species and reported directly to the participant. When the aggregate data from the EI
testing was compiled, the median (50th percentile) results for BLL and urinary arsenic were
compared to the age-adjusted median NHANES levels for BLL and urine arsenic.
4.3 Blood Lead Levels
Lead and Health Effects
Lead is a naturally occurring metal. Typically found at low levels in soil, lead is processed for
many industrial and manufacturing applications, and it is found in many metallic alloys. Lead
was banned as an additive to gasoline in 1996 and from paint in 1978. Lead can be found in all
parts of our environment because of past and current human activities including burning fossil
fuels, mining, and manufacturing processes [ATSDR 2007b]. Because of this, lead is often found
22

in the body at low levels. Lead exposure occurs primarily via the oral route, with some
contribution from the inhalation route. The toxic effects of lead are the same regardless of the
route of entry into the body.
Lead has no physiological value, and if it gets into the blood, lead can affect various organ
systems and be stored in the bones. Lead that is not stored in bones and teeth is excreted from the
body in urine and feces. About 99% of the amount of lead taken into the body of an adult will
leave the body in urine or feces within a couple of weeks, while about 30% of the lead taken into
the body of a child will leave the body in urine or feces [ATSDR 2007b]. Lead can stay in bones
for decades. Lead can leave bones and re-enter the blood and deposit in organs under certain
circumstances: during pregnancy and lactation, after a bone is broken, and during menopause in
women due to osteoporosis [ATSDR 2007b].
Depending on the level of exposure, lead can adversely affect the nervous system, kidney
function, immune system, reproductive system, development, and cardiovascular system. Lead
exposure also affects the oxygen carrying capacity of the blood. The lead effects most commonly
encountered in the current population are neurological effects in children, and cardiovascular
effects (e.g., high blood pressure and heart disease) in adults. Lead can be passed from a
mother’s body to negatively affect the health of her unborn child.
Exposure investigations that evaluate BLL usually emphasize the testing of pregnant women and
children younger than 6 years. Epidemiologic cohort studies suggest that prenatal lead exposure,
even with maternal BLLs <10 µg/dL, is inversely related to fetal growth and neurodevelopment
independent of the effects of postnatal lead exposure. Lead exposure can also cause a
miscarriage. Infants and young children are especially sensitive to even low levels of lead, which
may contribute to behavioral problems, learning deficits, and lowered IQ (intelligence quotient)
[Lanphear et al. 2005, Crump et al. 2013]. The exact mechanism(s) by which low-level lead
exposure, whether prenatal or postnatal, may adversely affect child development remains
uncertain [DHHS, 2010].
It is not known for certain if lead causes cancer in humans. Rats and mice fed large amounts of
lead in their food developed kidney tumors. The U.S. Department of Health and Human Services
classifies lead as “reasonably anticipated” to cause cancer and EPA considers lead a “probable”
cancer causing substance [ATSDR 2007b]. Because of the absence of any clear threshold for
some of lead’s more sensitive health effects, ATSDR has not established guidelines for a low or
no risk lead intake dose.
Currently a blood lead level of 5 µg/dL is used to identify children with blood lead levels greater
than most children in the U.S. These levels are known to have adverse effects. As a result, blood
lead levels should be kept as low as possible since no safe blood lead level in children has been
identified. In Montana, the reportable blood lead level is ≥ 5 µg/dL for all age groups.

23

An elevated level of lead in a person’s blood is an indication that an exposure has occurred. In
general, BLL correlates well with adverse health effects [ATSDR 2007b]. Young children and
the developing fetus are particularly sensitive to the effects of lead. The Pediatric Environmental
Health Specialty Units (PEHSU) provide recommendations for medical management of children
exposed to lead at all BLLs (Appendix D). CDC also provides a guide for recommended actions
based on BLL (https://www.cdc.gov/nceh/lead/advisory/acclpp/actions-blls.htm).
Some characteristics contribute to susceptibility (e.g., age, race, sex) and others to vulnerability
(e.g., socio-economic status and living in older housing). Living in older housing [CDC 2013,
Bernard et al. 2003], and poverty [CDC 2013, Jones et al. 2009] and being non-Hispanic black
[Bernard et al. 2003, CDC 2013, Jones et al. 2009] are risk factors for higher blood lead levels.
In Anaconda, living in poverty (28% below the poverty line) and living in older homes (80% of
homes were built before 1980) may indicate vulnerability of the Anaconda community to lead
exposure in addition to risk associated with site contamination.
Blood Lead Results
All 18 children younger than 6 years old who participated in the testing events measured a BLL
< 5 µg/dL. Similarly, all 54 children ages 6-19 who were tested had BLL values < 5 µg/dL.
Three adults (ages 58, 60 and 72) had BLL ≥ 5µg/dL (maximum of 9.14 µg/dL) with one
participant being tested in both events and having elevated results in both events. The results of
the questionnaire provided insight into the potential source of the BLL in the participants (e.g.,
participants lived in older homes for over 10 years, had hobbies associated with lead exposure, or
had their yard soil and attics tested and remediated). In addition to receiving a letter with their
results, the three participants were called by the EI Medical Officer to discuss their elevated
results and to provide recommendations to reduce exposure.
Figure 3 provides the blood lead levels found in the EI participants versus age. The dots in the
figure represent each of the participants in the EI where blood lead was analyzed. The figure
shows the age of each participant and the BLL in comparison to NHANES and the follow-up
level of 5 µg/dL. The black line indicates the 50th percentile (median) of the NHANES
population and the grey area outlines the area that reflects 90% of the NHANES population
(bordered on the top by the 95th percentile and on the bottom by the 5th percentile). The swish
pattern in the grey outline indicates higher lead concentrations at an early age due to greater
susceptibility of young children to lead exposure, including in utero, lower concentration in
adolescents resulting from rapid growth, and an increase of lead body burden in adults. This
pattern is consistent with current understanding of BLL distribution by age.

24

Figure 3: Anaconda Blood Lead Levels Compared to NHANES Values*

*NHANES 2015-2016 data set

Figure 3 provides the median estimates for Anaconda BLL compared to NHANES within
boxplots of the overall distribution of the EI and NHANES. ATSDR used post stratification to
match the age characteristics of the Anaconda EI group (which was generally older), as age is an
important predictor of blood lead levels. All participants tested had measurable lead in the blood
(level of detection = 0.07 µg/dL). In addition to comparing BLLs to the blood reference level of
5 µg/dL, BLLs were also compared to values that are representative of the median value found in
blood in the U.S. population (Figure 4). ATSDR used post stratification to match the age
characteristics of the Anaconda EI group (which was generally older), as age in an important
predictor of blood lead levels. The Anaconda residents had a median BLL of 1.1 µg/dL (95%
confidence interval [CI] 1.0 – 1.2 µg/dL) which was slightly higher compared to the median BLL
in age – adjusted NHANES of 0.95 µg/dL (95% CI 0.86 – 1.0 µg/dL) (difference of 0.15 µg/dL)
[CDC 2019a]. The difference is not clinically significant.

25

Figure 4: Boxplots of Anaconda blood lead levels compared to NHANES Values*

*NHANES 2015-2016 data set

Linear regression of the log transformed BLL values with the questionnaire results suggest that
occupational exposure to lead may be a contributing factor in BLL (Appendix E). After
controlling for the effects of age, diet and being male, we found that having a household member
employed in a construction or maintenance job, and entering their attic more than once per
month, were associated with higher BLLs.
4.4 Urinary Arsenic Levels
Arsenic and Health Effects
Arsenic is a naturally occurring element that is found in combination with either inorganic or
organic substances to form many different compounds. Arsenic often occurs naturally with lead.
Arsenic is also released into the environment from mining, ore smelting, and industrial use.
Inorganic arsenic compounds are of greater concern for toxicity than organic arsenic compounds
and are found in soils, sediments, groundwater, and some foods. People are most likely exposed
to excessive amounts of inorganic arsenic through drinking water. Other potential sources of
inorganic arsenic exposure can include contact with contaminated soil or with wood preserved
with arsenic. [ATSDR 2007c].
Fish and shellfish commonly contain organic arsenic compounds that can lead to organic arsenic
exposure in people consuming seafood. Chicken may also be a dietary source of organic arsenic.
Rice may be a source of dietary inorganic arsenic [CDC 2019b]. Organic arsenic is less toxic
26

than its inorganic form, which is generally associated with environmental exposures [Schoof
1999; ATSDR 2007c].
Inorganic arsenic is well absorbed from the gastrointestinal tract and, to a lesser degree, from
inhalation. Inorganic arsenic and its metabolites are rapidly metabolized and excreted from the
body with elimination half-lives of around 2-4 days. Therefore, urinary arsenic testing measures
only recent exposures [ATSDR 2007c; Orloff et al. 2009]. Inorganic arsenic crosses the human
placenta [ATSDR 2007b]. Inorganic arsenic is found in trivalent (arsenite) and pentavalent
(arsenate) forms. Trivalent arsenic is substantially more toxic and carcinogenic than pentavalent
arsenic [ATSDR 2007b]. Inorganic arsenic has been used as an outdoor wood preservative, as a
semiconductor in dopant materials, in some pesticides and in certain medicines.
Inorganic arsenic has been linked to skin, liver, bladder, and lung cancer, and the Department of
Health and Human Services (DHHS) has designated it as known to be a human carcinogen
[ATSDR 2007c].
Arsenic also induces a wide variety of non-cancer effects in humans. Unusually large doses of
inorganic arsenic can cause symptoms ranging from nausea, vomiting, and diarrhea to
dehydration and shock. Swelling of the face and cold-like symptoms which go away and are
followed by a rash or numbness are also associated with acute exposure [Mizuta 1956]. Longterm exposure to high levels of inorganic arsenic in drinking water has been associated with skin
disorders (e.g., hyperkeratosis and hyperpigmentation) and increased risks for diabetes and high
blood pressure [ATSDR 2007c].
All participants were tested for total arsenic as well as speciated arsenic in order to differentiate
organic from inorganic arsenic. Creatinine was also evaluated to correct for dilution variation.
For each participant, the total arsenic results were creatinine-corrected, as age-appropriate, and
compared to the 95th percentile NHANES values (2015-2016 data set for all species except
UTMO (2011-2012 data set); CDC 2019). For inorganic arsenic, ATSDR uses a conservative
approach by comparing the total of the participant’s inorganic arsenic species results (sum of
UAS5, UAS3, DMA and MMA) to NHANES values [CDC 2019]. Participants who exceed the
95th percentile NHANES value for total arsenic and total inorganic arsenic were contacted by the
ATSDR Medical Officer to discuss whether further evaluation may be warranted. The results of
the questionnaire were used to evaluate organic arsenic exposure, since most exposure to organic
arsenic is dietary.
Urine Arsenic Results
As indicated above, all urine specimens were analyzed for total arsenic, speciated arsenic,
creatinine and specific gravity. Seven arsenic species were analyzed: three methylated
metabolites (organic) [UASB, UASC and UTMO] and four inorganic arsenic species [UAS5,
UAS3, DMA and MMA]. The urine test results were creatinine-corrected, as age appropriate. To

27

evaluate urinary inorganic arsenic, the four inorganic arsenic species were combined because the
NHANES values provide comparison to the sum of the inorganic species.
Each participant’s creatinine-corrected, total urinary arsenic level and speciated arsenic levels
were compared to the 95th percentile value reported in NHANES [CDC 2019], as indicated in
Table 6.
Table 6. NHANES Levels (95th percentile) Used for Urinary Arsenic Comparison for
Individual Results

Age
Less than 3 yr
3 to 5 yrs
6 to 11 yrs
12 to 19 yrs
≥ 20 yrs

Total
Arsenic
NA
40.90
28.10
22.30
56.20

NHANES Level (µg/g Creatinine)*
Organic Arsenic
Inorganic
Arsenic†
UASB
UASC
NA
NA
NA
23.70
20.5
1.06
17.70
17.1
0.571
12.90
12.3
0.421
16.1
36.6
0.533

UTMO
NA
NA
1.06
<0.17
<0.17

* - Data from the 2015-2016 data set (CDC 2019); Data for UTMO was from the 2011-2012 data set
† - Inorganic arsenic includes a sum of UAS5, UAS3, DMA and MMA
NHANES = National Health and Nutritional Examination Survey; UASB = arsenobetaine; UASC = arenochloine;
UTMO = trimethylarsine; UAS5 = arsenic (V) acid; UAS3 = arsenous (III) acid; DMA = dimethylarsinic acid;
MMA = monomethylarsonic acid

The following conclusions were drawn based on this comparison for individual participants:
•

•

Total arsenic: four adult participants from the September testing and eight adult
participants from the November testing had total arsenic results greater than the agespecific NHANES values provided in Table 6.
o NHANES values are only provided for children 3 years or older. There was one
child younger than 3 years that had a higher-than-expected total urinary arsenic
result (87.1 µg/gm Cr), but there is no NHANES value that can be used for
comparison. Given the level, the child’s parents were called by the EI Medical
Officer to discuss the elevated results and to provide recommendations to reduce
exposure.
Inorganic arsenic: one adult participant from the September testing and one adult and one
child participant from the November testing had inorganic arsenic results greater than the
age-specific NHANES value provided in Table 6. The results of the questionnaire
provided insight into the potential source of the inorganic arsenic in the participants (e.g.,
participants have remodeled their home, including their attic or lived with a family
member that is employed in an occupation associated with metals exposure). In addition
to the standard results letter, the three participants were called by the EI Medical Officer
28

•

to discuss their elevated results and provided recommendations to reduce exposure.
Organic arsenic: approximately 5% of tested participants had organic arsenic that was
above the age-specific NHANES value provided in Table 9. The questionnaire provided
information that these residents had eaten a diet consisting of arsenic-containing foods
(e.g., fish, chicken, rice) in the week prior to testing.

Figure 5 provides the urinary levels for total arsenic found in all the EI participants versus age.
The urinary total arsenic levels include both organic and inorganic forms of arsenic with the
inorganic forms of arsenic being of potential health concern and the organic forms being
associated with exposure to arsenic in the diet. The dots in the figure represent each of the
participants in the EI where urinary total arsenic was analyzed. Figure 5 shows the age of each
participant and the urinary total arsenic level in comparison to NHANES and the age-specific
follow-up level for urinary total arsenic. The black line indicates the 50th percentile (median) of
the NHANES population and the grey area outlines the area that reflects 90% of the NHANES
population (bordered on the top by the 95th percentile and on the bottom by the 5th percentile).
Several participants had urinary total arsenic levels above the follow-up level, especially adult
participants.

29

Figure 5: Anaconda Urinary Total Arsenic Compared to NHANES*

*NHANES 2015-2016 data set

As noted above, there were several participants that had an elevated level of total arsenic in their
urine sample. Speciation of all urine samples was completed to determine whether urinary total
arsenic levels were associated with inorganic or organic forms of arsenic. Figure 6 provides the
urinary levels for inorganic arsenic, the more toxic form of arsenic, found in the EI participants
versus age. The dots in the figure represent each of the participants in the EI where urinary
inorganic arsenic was analyzed. The black line indicates the 50th percentile (median) of the
NHANES population and the grey area outlines the area that reflects 90% of the NHANES
population. Two adult and one child participants had slightly elevated urinary inorganic arsenic
levels. The EI Medical Officer discussed ways to reduce potential arsenic exposure with these
participants.
For urinary inorganic arsenic, one participant from the September testing (age 58) and two
participants from the November testing (age 3 and 74) had inorganic arsenic results greater than
the age-specific 95th percentile of NHANES. For perspective, if there were no differences
between the Anaconda EI participants and the U.S. population, we would have expected about
18 participants to be higher than the 95% due to chance alone. The EI Medical Officer called the
three participants were to discuss their elevated results and provide recommendations to reduce
exposure.

30

For organic arsenic, 16 EI participants had UASB greater than the 95th percentile of NHANES,
and four EI participants had UASC levels greater than the 95th percentile of NHANES. UTMO
was detected in four EI participants (detected values range from 0.276 – 7.2 µg/gm Cr). In the
NHANES 2011-2012 data set, it was detected in approximately 3% of the NHANES population
(range 0.11 – 9.2 µg/gm Cr).
Figure 6: Anaconda Urinary Inorganic Arsenic Compared to NHANES Values*

*NHANES 2015-2016 data set

ATSDR compared the Anaconda EI urinary total and inorganic arsenic to NHANES values in
(see Table 6 for NHANES values) at the 95th percentile, the median, as well as the 25th and 75th
quantile values (Figures 7, 8, 9, and 10). For the Anaconda EI participants, the median urinary
total arsenic of 6.7 of arsenic per gram of creatinine (µg/gm Cr) (95% CI 6.2 – 7.4 µg/gm Cr)
was 0.9 µg/gm Cr higher than the age-adjusted NHANES median of 5.8 (µg/gm Cr (95% CI 5.5
– 6.1 µg/gm Cr). However, Anaconda EI participants had a median urinary total inorganic of 4.6
µg/gm Cr (95% CI 4.3 – 4.8 µg/gm Cr), which was lower than the age – adjusted NHANES
median of 4.8 (95% CI 4.6 – 5.1 µg/gm Cr) (difference of 0.2 µg/gm Cr). This result indicates
that the increase in total arsenic is associated with organic arsenic. The responses to the
questionnaire, in which participants reported eating food potentially containing organic arsenic
(e.g., seafood, chicken) in the week preceding the testing, are consistent with this finding.
Organic arsenic is not harmful to humans at these levels [ATSDR 2007c].

31

Figure 7: Boxplots of Anaconda urinary total arsenic compared to NHANES*

*NHANES 2015-2016 data set

Figure 8: Boxplots of Anaconda urinary inorganic arsenic compared to NHANES*

*NHANES 2015-2016 data set

4.5 Correlation of Blood Lead and Urinary Arsenic Levels
ATSDR analyzed the correlation between BLL and urine arsenic levels. Pearson correlation
coefficients between log transformed urine total arsenic, urine inorganic arsenic, and blood lead
identified significant (p <0.01) correlations exist between urine and blood measurements, but the
32

strength of the relationship is weak between lead and total and inorganic arsenic (r = 0.22 and
0.26, respectively).
The weak correlation suggests that people with low BLL values may still be at risk for increased
urine arsenic values and vice versa. Public health actions should not assume that risk reduction
of exposure to one site contaminant ensures protective public health actions for the other
contaminant.

5.0 Limitations of this Exposure Investigation
All investigations have some inherent limitations. This EI has the following limitations:
•
•
•

The results of this EI are applicable only to the individuals tested and cannot be
generalized to other populations.
The results cannot be used to predict the future occurrence of disease in individuals.
The sampling offers insight into current levels of exposure to lead and arsenic. The
investigation methodology does not measure past exposures. Elevated blood lead
indicates there was exposure to lead. However, results do not provide information to
determine when the exposure occurred. As stated before, the results are a ‘snapshot in
time’ of current levels in peoples’ bodies.

6.0 EI Conclusions
•

•
•
•

•

The overall conclusion of the EI is that levels of blood lead and urinary arsenic measured
in residents of Anaconda that participated in the EI are comparable to the U.S.
population, as reported in NHANES.
All 18 children younger than 6 years old who participated in the testing events measured
a BLL below the 5 µg/dL follow-up level.
The median BLL for all EI participants was approximately 0.15 µg/dL higher than the
U.S. median, but this difference is not clinically significant.
For arsenic, Anaconda EI participants had a slight elevation in total urinary arsenic
(approximately 0.9 µg/gm Cr higher) compared to NHANES participants. The elevation
in total arsenic, however, appears to be attributable to organic arsenic given that the level
of inorganic arsenic was slightly lower (0.2 µg/gm Cr) than comparable NHANES
values. Organic arsenic enters the body through diet and is not toxic at these levels. The
organic arsenic testing results correlated to participants who reported eating foods high in
organic arsenic. ATSDR would not anticipate health effects associated with urine arsenic
levels measured in the Anaconda participants.
Evaluation of the questionnaire administered at the time of the testing suggests that
people can take measures to further reduce their exposure to lead. The analysis of
33

•

•

questionnaire data in relation to BLL indicates that people who reported working in
construction and maintenance jobs had higher BLLs.
Many Anaconda attics are contaminated with lead and arsenic as a result of smelter
activities in the past. Participants who reported entering their attics on a regular basis
generally had higher BLL and total arsenic than other participants.
The EI results do not mean that the risk of exposure to lead and arsenic in Anaconda
has been eliminated; residents should continue to be proactive in preventing exposure.

7.0 EI Recommendations
ATSDR identified specific actions, consistent with prudent public health practice that may
further reduce the risk of lead and arsenic exposures in Anaconda residents. ATSDR
recommends primary prevention efforts to avoid exposure to lead and arsenic in soil. ATSDR
supports the following recommendations and public health actions.
•

•

Anaconda citizens (including landlords) should participate in the Superfund Community
Soils OU residential yard and attic clean-up programs as a primary mechanism for
reducing potential exposure to lead and arsenic. Through the Superfund program (funded
by ARCO with EPA oversight), residents may opt for soil and attic testing. Based on the
results, residents can qualify for a contractor to clean contaminated attics. EPA and
ADLC should make efforts to increase participation in these programs. In the meantime,
ATSDR recommends that residents minimize time (or seal entryway) in untested or
contaminated (but not yet remediated) attics.
Anaconda citizens should take prudent actions to avoid contact with potentially
contaminated soil. These actions include:
o Avoid areas of known contamination (e.g., slag piles) and instruct children not to
play or ride bikes there;
o Supervise children closely to modify or eliminate risky hand-to-mouth behaviors
or intentional eating of dirt (pica behavior);
o Damp mop and damp dust surfaces;
o Cover bare soils with vegetation (grass, mulch, etc.) and create safe play areas for
children with clean ground cover;
o Remove shoes before entering the home;
o Bathe pets regularly to avoid them tracking contaminated soil into homes.

•

•

Anaconda citizens should take precautions to prevent exposure to lead from lead paint
during house renovations in homes build prior to 1978. Information is available at:
https://www.epa.gov/lead/protect-your-family-lead-your-home.
The EPA and ARCO should minimize risk of exposure to lead and arsenic from
uncovered slag through improved signage (specifically uncapped slag piles) and
Superfund remedial actions.
34

•

•

•

The ALDC Health Department should conduct regular BLL screenings for children under
age 6 based on risk identified from site contamination and the AAP recommendation
[AAP, 2016] of regular BLL screenings for communities with a significant portion of
homes built before 1960. Ensure venous draws and physician follow-up for capillary
BLL at or above the CDC Reference value of 5 µg/dL.
Primary healthcare providers should continue to improve understanding of lead screening
and ways to reduce exposure to site contaminants and lead paint. ATSDR’s Case Studies
in Environmental Medicine (CSEM) provide a self-instructional primer. The lead and
arsenic CSEMs are available at:
https://www.atsdr.cdc.gov/csem/csem.asp?csem=34&po=0
https://www.atsdr.cdc.gov/csem/csem.asp?csem=1&po=0
People working in jobs where lead and arsenic are present should use appropriate
personal protective equipment (PPE) while on the job to reduce exposure. Regular hand
washing and removing outer garments before entering the home after work reduces
exposures and protects family members.

8.0 Public Health Action Plan
The Public Health Action Plan for Anaconda contains a description of actions completed and
proposed actions by ATSDR, EPA and ARCO. The purpose of the EI is to ensure that we
identify exposures that may be of public health concern and to provide a plan of action designed
to prevent or mitigate adverse human health effects from contaminant exposure. ATSDR will
follow-up on this plan to ensure these actions are carried out.
8.1 Actions Completed
1. In December 2018 and February 2019, ATSDR sent each participant a letter informing
them of their BLL and urinary arsenic results and the EI Medical Officer called
participants that had levels above or approaching the follow-up level.
2. In September 2018, Grand Rounds were completed in Butte and Anaconda, MT.
Educational materials containing information regarding impacts of lead and arsenic were
provided to physicians in the area to assist with patient management.
8.2 On-going Actions
1. ARCO continues to test and remediate yard soil per their remediation plan under EPA
oversight.
2. ARCO continues to test attics per their remediation plan. Some of these may be
remediated.
3. The ADLC HD screens children in the Women, Infants, and Children (WIC) program for
lead exposure.
35

8.3 Actions Proposed
1. ATSDR will provide the results, conclusions and recommendations to the community in
a public meeting to be held in Anaconda the fall of 2019.
2. ATSDR will be available to community leaders and physicians in Anaconda to continue
to provide information and recommendations regarding how to reduce exposure to metals
in Anaconda.
3. ATSDR will partner with EPA, MT DPHHS and the ADLC HD to inform the Anaconda
community about the health benefits that can be gained by participating in existing soil
and attic remediation programs.
4. ATSDR will partner with MT DPPHS and ADLC to identify best practices in screening
children for lead exposure.
5. ATSDR will partner with EPA, MT DPHHS and the ADLC HD to educate workers with
potential occupational exposure to lead and arsenic about ways to reduce occupational
exposure and minimize tracking contamination into the home.

36

9.0 References
[AAP, 2016] Academy of Pediatrics, 2016. Prevention of Childhood Lead Toxicity. Pediatrics.
Available at:
https://pediatrics.aappublications.org/content/pediatrics/early/2016/06/16/peds.20161493.full.pdf. Accessed September 11, 2019
American Fact Finder, online, 2018. Percent of Related Children Under 18 Years Below Poverty
Level in the Past 12 Months.
https://factfinder.census.gov/faces/nav/jsf/pages/community_facts.xhtml
[ARCO 2008] Atlantic Richfield Corporation. 2008. Draft Final Community Soils Interior and
Attic dust Characterization Study Data Summary Report (DSR). Prepared by Pioneer
Technical Services for ARCO. January 2008.
[ARCO 2014] Atlantic Richfield Corporation. 2013. Anaconda Smelter Community Soils
Operable Unit: Lead and Arsenic Baseline Biomonitoring Study Report. Prepared for
Atlantic Richfield Company by ENVIRON International Corporation. June 2014.
[ATSDR 2007a] Agency for Toxic Substances and Disease Registry. 2007. Health Consultation:
Evaluation of Residential Soil Arsenic Action Level. Anaconda Co. Smelter Site,
Anaconda, Deer Lodge County, MT. EPA Facility ID: MTD093291656
[ATSDR 2007b] Agency for Toxic Substances and Disease Registry. 2007. Toxicological profile
for Lead. Atlanta, GA: U.S. Department of Health and Human Services, Public Health
Service.
[ATSDR 2007c] Agency for Toxic Substances and Disease Registry. 2007. Toxicological
profile for Arsenic. Atlanta, GA: U.S. Department of Health and Human Services,
Public Health Service.
[ATSDR 2018] Agency for Toxic Substances and Disease Registry. 2018. Personal
communication between David Dorian, ATSDR Region 8, and Charlie Partridge,
Toxicologist, U.S. Environmental Protection Agency. July 10, 2018.
Barbosa F, et al. 2005. A critical review of biomarkers used for monitoring human exposure to
lead: Advantages, limitations and future needs. Environmental Health Perspective, 2005,
113:1669-1674.
Bernard SM, McGeeing MA, Michael A.2003. Prevalence of Blood Lead Levels greater than 5
µg/dL Among U.S. Children 1 to 5 Years of Age and Socioeconomic and Demographic
Factors associated with Blood Lead Levels 5 to 10 µg/dL, Third National Health and
Nutrition Examination Survey, 1988 – 1994. Pediatrics 2003;112;1308.
[CDC 2012a] Centers for Disease Control and Prevention. Lead (web page). 2012a. Update on
Blood Lead Levels in Children. Last Updated October 30, 2012. Available online at:
http://www.cdc.gov/nceh/lead/ACCLPP/blood_lead_levels.htm

37

[CDC 2012b] Centers for Disease Control and Prevention. 2012b. Low Level Lead Exposure
Harms Children: A Renewed Call for Primary Prevention: Report of the Advisory
Committee on Childhood Lead Poisoning Prevention, Centers for Disease Control and
Prevention. U.S. Department of Health and Human Services, January. Available
at: http://www.cdc.gov/nceh/lead/acclpp/final_document_010412.pdf
[CDC 2012c] Centers for Disease Control and Prevention. 2012c. CDC Response to Advisory
Committee on Childhood Lead Poisoning Prevention Recommendations in "Low Level
Lead Exposure Harms Children: A Renewed Call of Primary Prevention". Centers for
Disease Control and Prevention, June 7, 2012. Available at:
http://www.cdc.gov/nceh/lead/ACCLPP/CDC_Response_Lead_Exposure_Recs.pdf
[CDC 2013] Centers for Diseases Control and Prevention. Blood Lead Levels in Children 1-5
Years-U.S. 1999-2010 (April 5, 2013) MMWR: Morbidity and mortality Weekly Report,
62913);245-248. Available at: http://www.cdc.gov/immigrantrefugeehealth/pdf/leadguidelines.pdf
[CDC 2019a] Centers for Disease Control and Prevention. Fourth Report on Human Exposure
to Environmental Chemicals, Updated Tables, (January 2019). Atlanta, GA: U.S.
Department of Health and Human Services, Centers for Disease Control and
Prevention. https://www.cdc.gov/exposurereport/
[CDC 2019b] Centers for Disease Control and Prevention. National Biomonitoring Program,
Arsenic Fact Sheet. Available at;
https://www.cdc.gov/biomonitoring/Arsenic_FactSheet.html. Accessed September 13,
2019.
[Census Bureau 2010] U.S. Census Bureau. 2010. Online. https://www.census.gov/
[Census Bureau 2013-2017] U.S. Census Bureau, 2013-2017 American Community Survey 5Year Estimates. Available at https://factfinder.census.gov/faces/tableservices. Accessed:
September 11, 2019
Crump KS, Van Landingham C, et al., 2013. A statistical reevaluation of the data used in the
Lanphear et al. (2005) pooled-analysis that related low levels of blood lead to intellectual
deficits in children. Crit Rev Toxicol 43:785-799.
[DHHS 2010] U.S. Department of Health and Human Services. 2010. Atlanta, Georgia.
Guidelines for the Identification and Management of Lead Exposure in Pregnant and
Lactating Women. November 2010. U.S. Department of Health and Human Services.
[DHHS 2011] U.S. Department of Health and Human Services. 2011. Washington, DC.
American Healthy Homes Survey. Lead and Arsenic Findings Office of Healthy Homes
and Lead Hazard Controls. April 2011. U.S. Department of Health and Human Services.
Available at https://www.hud.gov/sites/documents/AHHS_REPORT.PDF. Accessed
September 11, 2019.
Dixon SL, Gaitens JM, et al., 2009. Exposure of U.S. Children to Residential Dust Lead, 19992004: II. The contribution of lead contaminated dust to children’s blood lead levels.

38

Environmental Health Perspective 117:468-474. Available at:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2661919/
[EPA 1996] U. S. Environmental Protection Agency. 1996. EPA Superfund Record of Decision:
Anaconda Company Smelter. Denver: U.S. Environmental Protection Agency, Region 8.
EPA/ROD/R08-96/127. September 1996.
https://cumulis.epa.gov/supercpad/SiteProfiles/index.cfm?fuseaction=second.scs&id=08
00403&doc=Y&colid=32604®ion=08&type=SC
[EPA 2008] U.S. Environmental Protection Agency. 2008. Residential Soils Interpretation and
Analysis Report; Community Soils Operable Unit, Anaconda Smelter NPL Site. 2008.
[EPA 2013] U.S. Environmental Protection Agency. 2013. Record of Decision (ROD)
Amendment, Community Soils Operable Unit, Anaconda Smelter National Priorities
List Site. Anaconda, MT. EPA ID: MTD093291656. Community Soils Operable Unit.
September 2013.
https://cumulis.epa.gov/supercpad/SiteProfiles/index.cfm?fuseaction=second.scs&id=08
00403&doc=Y&colid=32604®ion=08&type=SC
[EPA 1994] U.S. Environmental Protection Agency. 1994. Draft Baseline Risk Assessment for
Lead, Expedited Response Action Priority Soils Operable Unit Silver Bow Creek/Butte
Area NPL Site, Butte Montana.
[EPA 2015] U.S. Environmental Protection Agency. 2015. Fifth Five-Year Review Report.
Anaconda Smelter Superfund Site. Anaconda-Deer Lodge County, MT. EPA ID:
MTD093291656.
https://cumulis.epa.gov/supercpad/SiteProfiles/index.cfm?fuseaction=second.scs&id=080
0403&doc=Y&colid=32604®ion=08&type=SC
Hinwood AL, Sim MR, de Klerk N, Drummer O, Gerostamoulos J, Bastone EB. Are 24-hour
urine samples and creatinine adjustment required for analysis of inorganic arsenic in
urine in population studies? Environ Res Section A. 88, 219–224.
Jones R, Homa D, Meyer P, et al. 2009. Trends in Blood Lead Levels and Blood Lead Testing
Among U.S. Children aged 1- 5 Years, 1988-2004. Pediatrics 2009. Mar; 123(3):e376385 Available at: http://pediatrics.aappublications.org/content/123/3/e376.full.pdf+html
Lanphear, BP, Hornung, R et al. 2005. Low-level environmental lead exposure and children’s
intellectual function: An international pooled analysis. Environ Health Perspect 113:894899.
Lumley T. 2019. survey: analysis of complex survey samples. R package version 3.35-1.
Manly, B. F. J. (2007). Randomization, Bootstrap and Monte Carlo Methods in Biology, Third
Edition. Boca Raton, FL, Chapman & Hall/CRC.
[NIOSH 2015]. National Institute for Occupational Safety and Health. Online.
https://www.cdc.gov/niosh/topics/ables/description.html

39

Orloff K, Mistry K, Metcalf S. Biomonitoring for Environmental Exposures to Arsenic. Journal
of Toxicology and Environmental Health, Part B: Critical Reviews. 2009. 12:7, 509-524.
Available at http://dx.doi.org/10.1080/10937400903358934
R Core Team. 2019. R: A language and environment for statistical computing. Version 3.5.3. R
Foundation for Statistical Computing, Vienna, Austria. URL https://www.R-project.org/
Schoof RA, Eickhoff J, Yost LJ, et al. 1999a. Dietary exposure to inorganic arsenic. In:
Chappell WR, Abernathy CO, Calderon RL, eds. Arsenic exposure and health
effects. Amsterdam: Elsevier Science, 81-88.

40

Authors
Karen Scruton, MS
Environmental Health Scientist
Science Support Branch (SSB)
Division of Community Health Investigations (DCHI)
David Dorian, MS
Regional Representative
Region 8 ATSDR
Division of Community Health Investigations (DCHI)
Kai Elgethun, PhD, MPH
Regional Director
Region 8 ATSDR
Division of Community Health Investigations (DCHI)
Rene Suarez-Soto, MS
Science Support Branch
Division of Community Health Investigations (DCHI)
Data Analysis and Exposure Investigation Team
James Durant, MS
Science Support Branch
Division of Community Health Investigations (DCHI)
Data Analysis and Exposure Investigation Team
Matthew Ferguson, PhD
State Toxicologist
Montana Department of Public Health and Human Service (DPHHS)

41

Acknowledgements
ATSDR is appreciative of the personnel who were involved in recruitment, sampling and data
analysis for the EI, including ATSDR Personnel:
•
•
•
•

Dr. Lourdes Rosales-Guevara
Dr. Arthur Wendel
Loretta Asbury
Susan McBreairty

EPA Personnel:
•
•

Charles Partridge
Charles Coleman

Division of Laboratory Services (DLS) at the National Center for Environmental Health
(NCEH):
•
•
•

Sina De Leon Salazar
Kathleen Caldwell
Angela Hicks

Anaconda Deer Lodge County Health Department (ADLC HD)
•

Kitty Basirico

Montana Department of Public Health and Human Services (MTDPHHS)
Laura Williamson
Todd Harwell
Connie Garrett
Heather Welch
Hallie Koeppen
Kristen Rogers
Lisa Schmidt
Jen Fladager

Matthew Ferguson
Jessica Miller
Dorota Carpenedo
Victoria Troeger
Carrie Oser
Robin Silverstein
Alex Long
Heather Zimmerman

Finally, ATSDR wants to thank the community, for its participation and collaboration on this EI,
including members of the Anaconda city council and local government.

42

Appendix A: Anaconda Deer Lodge County Map and Demographics

43

Appendix B: Summary of Cancer Incidence in Anaconda Deer Lodge County
In 2018, residents of Anaconda expressed concern to local and state agencies that there may be
too much cancer in the Anaconda community. Also, people were not sure what kinds of cancer
among Deer Lodge County residents might be related to the heavy metal contamination. The
Montana Cancer Control Program conducted analyses to determine if new cancer cases and
cancer death rates among Deer Lodge County residents from 1985-2016 were statistically the
same as the rest of Montana. The rate of new cancer cases remains the same among Deer Lodge
County residents when compared to all Montana residents. Similar results were observed for
rates of cancer deaths where no significant differences were observed.
Residents also wanted to know what cancers were associated with arsenic and lead exposures.
Currently, there is no conclusive evidence that lead causes cancer in humans. However, arsenic
is known to cause lung, urinary bladder, and skin cancers; and it is also associated with kidney,
liver, and prostate cancers. The Montana Department of Public Health and Human Services
(DPHHS) looked and compared data specific to these cancer types. Using data from 1985 to
2016, there were no significant differences between Deer Lodge County residents and the state’s
rates of observed new cancer cases for lung cancer, prostate cancer, kidney cancer, and bladder
cancer (looking at a range of years from 1985-2016). Finally, Anaconda census tracks were
identified and incidence rates within these areas were used to compare to the expected number of
cases (Figure D.1). Since 2009 and with an average of 38 new cancer cases identified among
Anaconda residents each year, the rates of new cancers cases are not occurring at rates higher
than the rest of Montana.
45

Expected

40

Number of new cancers

35
30

Observed

25
20
15
10
5
30

42

38

45

2009

2010

2011

2012

43

37

28

39

2013

2014

2015

2016

0

Year

Figure D.1 Number of new cancer cases observed among Anaconda residents compared to how
many were expected
44

Appendix C: Demographic and 2010 Census Information

45

Appendix C. Demographic Information
Testing Event
September

November

Total

Info from 2010
Census*

Children Younger than 6 yrs
3/191 (1.6%)

15/177 (8.5%)

18/368 (4.9%)

348/9,139
(3.8%)

Gender
Children (≤ 19yrs)
Male
Female
Adult (≥ 20 yrs)
Male
Female

17/28 (61%)
11/28 (39%)

28/44 (64%)
16/44 (36%)

45/72 (63%)
27/72 (38%)

68/163 (42%)
95/163 (58%)

60/133 (45%)
73/133 (55%)

128/296 (43%)
168/296 (57%)

NA

Ethnicity
Mexican Descent
Children
Adults

4/28 (14%)
3/163 (2%)

1/44 (2%)
3/133 (2%)

5/72 (7%)
6/296 (2%)

3%

42/44 (95%)
127/132 (96%)

67/69 (97%)
284/293 (97%)

93%

2/44 (5%)
4/132 (3%)

2/69 (3%)
7/293 (2%)

3%

97/133 (73%)

223/296 (75%)

NA

164/177 (93%)

343/368 (93%)

NA

39/44 (89%)

61/72 (85%)

80%

Race†
White
Children
Adults

25/25 (100%)
157/161 (98%)

American Indian/Alaska Native
Children
Adults

0/25 (0%)
3/161 (2%)

Home Information
Lived in Anaconda more than 10 yearsǂ
Adults

126/163 (77%)

Lives in a Single Family Home
Residents

179/191 (94%)

Lives in a home older than 1980
Children

22/28 (79%)

46

Adults

126/163 (77%)

101/133 (76%)

227/296 (77%)

EPA has removed soil from resident’s yard
Residents
44/191(23%)
Attic professionally clean
Residents
18/191 (9%)

54/177 (31%)

98/368 (27%)

NA

18/177 (10%)

36/368 (10%)

NA

Lifestyle
Lives in a home where someone works at a job associated with lead exposure
Residents

35/191 (18%)

53/177 (30%)

88/368 (24%)

NA

Takes off shoes before entering home (never or seldom)§
Residents

105/190 (55%)

85/176 (48%)

190/366 (52%)

NA

131/368 (36%)
167/368 (45%)
307 (368 (83%)

NA

Diet of Participants
Seafood
Rice
Chicken

55/191 (29%)
84/191 (44%)
154/191 (81%)

76/177 (43%)
83/177 (47%)
153/177 (86%)

*

The demographic information from the 2010 census is provided in Appendix A.
Three children and two adults in the September testing and 1 adult in the November testing did not respond to the
race question
ǂ The results represent the number of adults that have lived in Anaconda more than 10 years since the results for
children vary by the child’s age
§ One participant in each sampling event did not answer the question regarding shoe removal
†

47

Appendix D: PESHU Recommendations for Lead

Recommendations on Medical Management of Childhood Lead Exposure and
Poisoning
No level of lead in the blood is safe. In 2012, the CDC established a new “reference value” for
blood lead levels (5 mcg/dL), thereby lowering the level at which evaluation and intervention are
recommended (CDC).
Lead level
Recommendation
< 5 mcg/dL
1. Review lab results with family. For reference, the geometric mean blood lead level for
children 1-5 years old is less than 2 mcg/dL.
2. Repeat the blood lead level in 6-12 months if the child is at high risk or risk changes during the
timeframe. Ensure levels are done at 1 and 2 years of age.
3. For children screened at age < 12 months, consider retesting in 3-6 months as lead exposure
may increase as mobility increases.
4. Perform routine health maintenance including assessment of nutrition, physical and mental
development, as well as iron deficiency risk factors.
5. Provide anticipatory guidance on common sources of environmental lead exposure: paint in
homes built prior to 1978, soil near roadways or other sources of lead, take-home exposures
related to adult occupations, imported spices, cosmetics, folk remedies, and cookware.
5-14 mcg/dL 1. Perform steps as described above for levels < 5 mcg/dL.
2. Re-test venous blood lead level within 1-3 months to ensure the lead level is not rising. If it is
stable or decreasing, retest the blood lead level in 3 months. Refer patient to local health
authorities if such resources are available. Most states require elevated blood lead levels be
reported to the state health department. Contact the CDC at 800-CDC-INFO (800-232-4636)
or the National Lead Information Center at 800-424-LEAD (5323) for resources regarding lead
poisoning prevention and local childhood lead poisoning prevention programs.
3. Take a careful environmental history to identify potential sources of exposures (see #5 above)
and provide preliminary advice about reducing/eliminating exposures. Take care to consider
other children who may be exposed.
4. Provide nutritional counseling related to calcium and iron. In addition, recommend having a
fruit at every meal as iron absorption quadruples when taken with Vitamin C-containing foods.
Encourage the consumption of iron-enriched foods (e.g., cereals, meats). Some children may
be eligible for Special Supplemental Nutrition Program for Women, Infants and Child (WIC) or
other nutritional counseling.
5. Ensure iron sufficiency with adequate laboratory testing (CBC, Ferritin, CRP) and treatment
per AAP guidelines. Consider starting a multivitamin with iron.

48

6. Perform structured developmental screening evaluations at child health maintenance visits, as
lead’s effect on development may manifest over years.
15-44 mcg/dL 1. Perform steps as described above for levels 5-14 mcg/dL.
2. Confirm the blood lead level with repeat venous sample within 1 to 4 weeks.
3. Additional, specific evaluation of the child, such as abdominal x-ray should be considered
based on the environmental investigation and history (e.g., pica for paint chips, mouthing
behaviors). Gut decontamination may be considered if leaded foreign bodies are visualized on
x-ray. Any treatment for blood lead levels in this range should be done in consultation with
an expert. Contact local PEHSU or PCC for guidance; see resources on back for contact
information.
>44 mcg/dL
1. Follow guidance for BLL 15-44 mcg/dL as listed above.
2. Confirm the blood lead level with repeat venous lead level within 48 hours.
3. Consider hospitalization and/or chelation therapy (managed with the assistance of an
experienced provider). Safety of the home with respect to lead hazards, isolation of the lead
source, family social situation, and chronicity of the exposure are factors that may influence
management. Contact your regional PEHSU or PCC for assistance; see resources on back for
contact information.
Document authored by Nicholas Newman, DO, FAAP, Region 5 PEHSU, Helen J. Binns, MD, MPH, Region 5 PEHSU,
Mateusz Karwowski, MD, MPH, Region 1 PEHSU, Jennifer Lowry, MD , Region 7 PEHSU and the PEHSU Lead
Working Group.

Principles of Lead Exposure in Children
•

A child’s blood lead concentration depends on their environment, habits, and nutritional status. Each of these
can influence lead absorption. Children with differing habits or nutritional status but who live in the same
environment can vary on blood lead concentration. Further, as children age or change residences, habits or
environments change creating or reducing lead exposure potential.

•

While clinically evident effects such as anemia, abdominal pain, nephropathy, and encephalopathy are seen at
levels >40 µg/dL, even levels below 10 µg/dL are associated with subclinical effects such inattention and
hyperactivity, and decreased cognitive function. Levels above 100 µg/dL may result in fatal cerebral edema.

•

Lead exposure can be viewed as a lifelong exposure, even after blood lead levels decline. Bone acts as a
reservoir for lead over an individual’s lifetime. Childhood lead exposure has potential consequences for adult
health and is linked to hypertension, renal insufficiency, and increased cardiovascular-related mortality.

•

Since lead shares common absorptive mechanisms with iron, calcium, and zinc, nutritional deficiencies in
these minerals promotes lead absorption. Acting synergistically with lead, deficiencies in these minerals can
also worsen lead-related neurotoxicity.

49

Principles of Lead Screening
•

Lead screening is typically performed with a capillary specimen obtained by a finger prick with blood blotted
onto a testing paper. Testing in this manner requires that the skin surface be clean; false positives are
common. Therefore, elevated capillary blood lead levels should be followed by venipuncture testing to
confirm the blood lead level. In cases where the capillary specimen demonstrates an elevated lead level but
the follow-up venipuncture does not, it is important to recognize that the child may live in a leadcontaminated environment that resulted in contamination of the finger tip. Efforts should be made to identify
and eliminate the source of lead in these cases. Where feasible, lead screening should be performed by
venipuncture.

Principles of Iron Deficiency Screening
•
•

The iron deficiency state enhances absorption of ingested lead.
Hemoglobin is a lagging indicator of iron deficiency and only 40% of children with anemia are iron deficient.

•

Lead exposed children (≥ 5 mcg/dL) are at risk for iron deficiency and should be screened using CBC, Ferritin,
and CRP. Alternatively, reticulocyte hemoglobin can be used, if available.

•

Children with iron deficiency, with or without anemia, should be treated with iron supplementation.

Resources
•

Pediatric Environmental Health Specialty Unit
(PEHSU) Network

•

www.pehsu.net or 888-347-2632

•

Poison Control Center (PCC)

•

www.aapcc.org/ or 800-222-1222

•

Centers for Disease Control and Prevention

•

www.cdc.gov/nceh/lead/ or 800-232-4636

•

U.S. Environmental Protection Agency

•

www.epa.gov/lead/ or 800-424-5323

Suggested Reading and References:
Pediatric Environmental Health, 3rd edition. American Academy of Pediatrics, 2012.
Woolf A, Goldman R, Bellinger D. Pediatric Clinics of North America 2007;54(2):271-294.
Levin R, et al. Environmental Health Perspectives 2008; 116(10):1285-1293.
Baker RD, Greer FR. Pediatrics 2010;126(5):1040-50.
Guidelines for the Identification and Management of Lead Exposure in Pregnant and Lactating Women. CDC, 2010.
CDC Response to Advisory Committee on Childhood Lead Poisoning Prevention Recommendations in “Low Level Lead Exposure Harms Children: A
Renewed Call of
Primary Prevention” June 7, 2012
This document was supported by the Association of Occupational and Environmental Clinics (AOEC) and funded (in part) by the cooperative
agreement award number 1U61TS000118-04 from the Agency for Toxic Substances and Disease Registry (ATSDR).
Acknowledgement: The U.S. Environmental Protection Agency (EPA) supports the PEHSU by providing funds to ATSDR under Inter-Agency
Agreement number DW-7592301301-0. Neither EPA nor ATSDR endorse the purchase of any commercial products or services mentioned in
PEHSU publications. (June 2013 update)

50

Appendix E: Analysis of Blood Lead and Total Urinary Arsenic Levels for
Anaconda Participants
Methods
We matched participant questionnaire results with laboratory results for lead and arsenic by
participant identification number. There was one participant who returned for retesting in
November, so we averaged the results of blood lead and urinary arsenic for this participant.
Geometric means were calculated for the questions and 95% confidence intervals were generated
using t-statistics of the log-transformed values [Helsel 2012]. We combined categorical
responses that had a low number of responses for the purposes of analysis. Since there were
often multiple participants from a single address, linear mixed effects model (lmer) [Kuznetsova
et al. 2017] was used to age adjust measures of association by demographic and questionnaire
responses using a b-spline to account for the non-linear effects of age. We modeled each address
as a random intercept in the lmer to account for random differences in lead levels at each
address. Since the regression was performed on the log transformed variable, the measures of
effect (Beta) are ratios of model predicted geometric means after controlling for the effect of age.
We first performed analysis of each questionnaire individually (bi-variate analysis), controlling
for the fixed effects of age, and the random effect of address. From the bivariate analysis, we
considered any factor with a p-value less than 0.1 as a candidate factor in the multivariate
analysis. After elimination of redundant and collinear variables (such as time in Anaconda, time
at address), we used forward selection of variables using corrected Akaike Information Criterion
to arrive at the best fitting lmer [Long 2012]. We modeled only blood lead and total urinary
arsenic because they were slightly higher than the referent age adjusted NHANES 2015 – 2016
population. If the participant was a minor, ATSDR asked 3 specific questions related to potential
for hand – mouth transfer of dust or direct ingestion of soil. We analyzed these questions
individually for the 71 participants who were minors but did not develop a full multivariate
model because of the small sample size.
Results
Blood lead
Results of the bivariate analysis are shown in Tables

Table E - 1 and E - 2. In addition to age and sex, we found the following to be potentially
associated with higher blood lead levels after controlling for the effect of age:
•
•
•

hours per day outside, (greater than 6 hours),
entry into attic (respondent entering on daily or weekly basis),
peeling paint in house (do not know),
51

•
•
•
•

changing clothes (sometimes or always),
occupation (self-reported job with contact with lead or slag, construction work,
mechanical work),
self-reported hobbies with contact with lead (firearms, hunting, or fishing), and
consumption of 3 or more servings of rice in past week.

We found the following questionnaire responses to be potentially associated with lower blood
lead levels after controlling for the effects of age:
•
•
•
•

time at address (greater than 2 years),
removing shoes (sometimes or always),
never entering attic, and
consumption of chicken in past week.

In the final fully adjusted model (Table E - 3), the lowest AICc was produced by a spline of age,
with additive factors of sex, construction or maintenance, consumption of chicken, and entry into
attic (daily or weekly). The marginal and conditional r – squared was 0.32 and 0.68,
respectively, with an AICc of 493.85. To show the overall impact of these responses on blood
lead in the lmer, predicted marginal geometric means were plotted for a 49.88 year old male
(Figure E - 1) and showing all ages by sex (Figure E - 2) (Lüdecke 2018). In general, marginal
effects were below 1 µg/dL, consistent with the comparison of the Anaconda EI participants to
the NHANES 2015 – 2016. Children who responded as having behaviors that would increase
soil or dust ingestion had slightly higher blood lead levels, but the effects on blood lead had
relatively high p values, so we could not rule out the effects being a result of statistical chance
alone (Table E - 2).
Urinary Total Arsenic
For urinary arsenic, we show results of the bivariate analysis in Table E - 4. After controlling for
the effects of age, questionnaire responses that were potentially associated in the bivariate
analysis with increased total urinary arsenic:
•
•
•
•
•

sex (male),
daily or weekly entry into attic,
remove shoes (sometimes or always),
use vacuum cleaner (several times a week or monthly),
consume seafood

The following questionnaire responses were associated in the bivariate analysis with decreased
total urinary arsenic:
•
•

Enter attic (yearly), and,
Change clothing when entering home (seldom do this, always do this).
52

As with the lead results, the child specific questions were not statistically associated with urinary
total arsenic (Error! Reference source not found.). The model with the lowest AICc consisted
of a spline of age and additive terms for sex, consumption of seafood, and entry into attic (Table
E - 6).

References
Helsel, DR. 2011. Statistics for Censored Environmental Data Using Minitab and R, Wiley.
Kuznetsova A, Brockhoff PB, Christensen RHB. 2017. “lmerTest Package: Tests in Linear
Mixed Effects Models. Journal of Statistical Software, 82(13), 1-26. doi: 10.18637/jss.v082.i13.
(URL: http://doi.org/10.18637/jss.v082.i13)
Long JD. 2012. Longitudinal Data Analysis for the Behavioral Sciences Using R. Sage.
Lüdecke, D. ggeffects: Tidy Data Frames of Marginal Effects from Regression Models.” Journal
of Open Source Software, 3(26), 772. doi: 10.21105/joss.00772 (URL:
http://doi.org/10.21105/joss.00772)

53

Tables

Table E - 1: Participant Questionnaire Results and Age-Adjusted Estimates of Association with Blood Lead, Anaconda EI (N=367, 9
missing blood lead results)
Abbreviations: CI: Confidence Interval, NA: Not Applicable, Ref: Reference Factor Level, SE: Standard Error

Risk Factor
What is your or your child/ward’s
sex?
City
Are you or your child/ward
Hispanic, Latino/a, or Spanish
Origin? (one or more
categories may be selected)
What is your or your child/ward’s
race? (one or more categories may
be
selected)

Do you or your child/ward spend
time outside the home (e.g., work or
daycare/school)?
If yes, how long are your or your
child/ward out of the house during

Value

Number of
participants
[missing blood lead]

Geometric mean
blood lead
[95% CI]

Female

194 [5]

1 [0.93--1.1]

Male

173 [4]

Anaconda
Bozeman or Deer Lodge
No
Yes

Estimate
[SE]

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

Ref

Ref

1.2 [1.1--1.4]

Ref
0.28
[0.046]

1.3 [1.2--1.4]

<0.001

358 [8]
9 [1]
355 [8]
11 [0]

1.1 [1--1.2]
1.1 [0.71--1.7]
1.1 [1--1.2]
0.97 [0.63--1.5]

Ref
-0.13 [0.25]
Ref
0.16 [0.17]

Ref
0.88 [0.54--1.4]
Ref
1.2 [0.84--1.6]

Ref
0.595
Ref
0.360

(Missing)
White
Other

1 [1]
352 [8]
9 [0]

NA
1.1 [1--1.2]
1.3 [0.81--2.2]

NA
Ref
0.24 [0.19]

NA
Ref
1.3 [0.88--1.8]

NA
Ref
0.205

(Missing)
No

6 [1]
43 [0]

0.7 [0.34--1.4]
1.5 [1.2--1.7]

NA
Ref

NA
Ref

NA
Ref

Yes

324 [9]

1.1 [1--1.2]

-0.043
[0.098]

0.96 [0.79--1.2]

0.658

0 hours
1 to 4 hours

36 [0]
86 [2]

1.4 [1.2--1.7]
1.2 [1.1--1.4]

Ref
-0.06 [0.12]

Ref
0.94 [0.75--1.2]

Ref
0.605

Risk Factor

Value

Number of
participants
[missing blood lead]

Geometric mean
blood lead
[95% CI]

the day?

If you or your child/ward are out of
the house during the day, how many
times
per week?

How many hours per day do you or
your child/ward typically spend
outdoors?

Approximately when was the
building built?

How many hours per day do you or
your child/ward typically spend in
your attic?

Does you or your child/ward wash
hands before eating?

5 to 8 hours

79 [1]

1.1 [1--1.3]

Over 8 hours
(Missing)

165 [6]
1 [0]

0.99 [0.89--1.1]
NA

0 days
1-3 days per week

36 [0]
24 [0]

1.4 [1.2--1.7]
0.9 [0.64--1.3]

4 or more days per week

306 [9]

(Missing)
Do not spend time
outdoors
2 to 4 hours per day

Estimate
[SE]
-0.012
[0.12]
0.052
[0.12]
NA

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

0.99 [0.79--1.2]

0.921

1.1 [0.84--1.3]
NA

0.654
NA

Ref
0.82 [0.61--1.1]

Ref
0.175

1.1 [1--1.2]

Ref
-0.2 [0.15]
0.0071
[0.11]

1 [0.82--1.2]

0.946

1 [0]

NA

NA

NA

NA

7 [0]
150 [4]

1.3 [0.61--2.8]
1 [0.92--1.1]

Ref
0.15 [0.22]

Ref
1.2 [0.76--1.8]

Ref
0.491

4 to 6 hours per day
Less than 2 hours per
day

59 [1]

1.1 [0.96--1.3]

0.21 [0.23]

1.2 [0.79--1.9]

0.351

104 [4]

1.1 [0.95--1.2]

0.14 [0.22]

1.1 [0.74--1.8]

0.535

Over 6 hours per day
(Missing)
pre1980

46 [0]
1 [0]
287 [4]

1.5 [1.3--1.8]
2.9
1.1 [1.1--1.2]

0.52 [0.23]

1.7 [1.1--2.6]

0.024

Ref

Ref

post1980

62 [3]

1.1 [0.93--1.3]

0.99 [0.83--1.2]

0.926

Don’t know

17 [2]

0.84 [0.6--1.2]

Ref
-0.0085
[0.092]
-0.069
[0.16]

0.93 [0.68--1.3]

0.675

(Missing)
Do not spend time in
attic

1 [0]

NA

NA

NA

NA

343 [9]

1.1 [1--1.2]

Ref

Ref

Ref

Spend time in attic

16 [0]

1.7 [1.3--2.2]

0.32 [0.14]

1.4 [1.1--1.8]

0.021

(Missing)
Always

8 [0]
231 [4]

1.2 [0.67--2]
1.2 [1.1--1.3]

NA
Ref

NA
Ref

Never or Sometimes

136 [5]

1 [0.92--1.2]

NA
Ref
0.19
[0.069]

1.2 [1.1--1.4]

0.007

2

Risk Factor
How long have you lived at this
address?

Do you speak a language other than
English at home? (5 years or older)

Do you live in a(n):

Do the windows (e.g., sills) have
peeling paint?
Is there peeling paint in other places
such as cabinets, interior walls
and/or
exterior walls?

Any peeling paint

How often do you clean your home
using a wet mop?

Number of
participants
[missing blood lead]
15 [1]

Geometric mean
blood lead
[95% CI]
1.5 [1--2.2]

18 [0]
81 [3]
52 [2]
200 [3]
1 [0]
353 [9]

1.3 [0.93--1.8]
0.98 [0.85--1.1]
0.95 [0.81--1.1]
1.2 [1.1--1.3]
NA
1.1 [1--1.2]

Yes
(Missing)

11 [0]
3 [0]

1.6 [0.96--2.5]
1.3 [0.088--20]

Single Family Home
Apartment, Townhouse,
Condominium, or Other

342 [8]

1.1 [1.1--1.2]

18 [1]

0.88 [0.66--1.2]

Mobile Home
No

7 [0]
293 [7]

1.2 [0.62--2.3]
1.1 [1.1--1.2]

Yes
No
Do not know

74 [2]
261 [7]
3 [0]

0.99 [0.86--1.1]
1.1 [1--1.2]
2.4 [1.9--3.1]

Yes

96 [2]

1.1 [0.94--1.2]

(Missing)
No

7 [0]
228 [5]

1.6 [1--2.7]
1.1 [1.1--1.2]

Yes

133 [4]

(Missing)
Daily to several times a
week
Weekly to Monthly

Value
Less than 6 months
6 months to less than 2
years
2 to 5 years
6 to 10 years
More than 10 years
(Missing)
No

Ratio of
Geometric
Means [CI]
Ref

p value
(fixed
effects)
Ref

-0.28 [0.22]
-0.35 [0.18]
-0.59 [0.18]
-0.54 [0.17]
NA
Ref
0.045
[0.17]
NA

0.76 [0.49--1.2]
0.7 [0.5--1]
0.55 [0.39--0.79]
0.58 [0.42--0.82]
NA
Ref

0.205
0.053
0.001
0.002
NA
Ref

1 [0.74--1.5]
NA

0.797
NA

Ref
-0.097
[0.17]

Ref

Ref

0.91 [0.65--1.3]

0.577

-0.13 [0.25]
Ref
-0.057
[0.083]
Ref
0.92 [0.32]
0.12
[0.077]

0.88 [0.54--1.4]
Ref

0.594
Ref

0.94 [0.8--1.1]
Ref
2.5 [1.3--4.7]

0.491
Ref
0.004

1.1 [0.97--1.3]

0.115

NA
Ref

NA
Ref

1.1 [0.94--1.2]

NA
Ref
0.037
[0.07]

1 [0.9--1.2]

0.600

6 [0]

1.7 [0.92--3]

NA

NA

NA

46 [1]

1.2 [1—1.4]

Ref

Ref

284[8]

1.1 [1.1--1.2]

Ref
-0.065
[0.099]

0.94 [0.77--1.1]

0.512

Estimate
[SE]
Ref

3

Risk Factor

How often do you clean your home
using a vacuum cleaner?

Value

Number of
participants
[missing blood lead]

Geometric mean
blood lead
[95% CI]

If you have an attic in your home,
how often do you enter the attic?
Have you had your attic cleaned, if
yes, when was it cleaned?

Does your home have a yard with
bare dirt?
Has soil in your yard been removed
and replaced with clean soil?

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

Other

37 [0]

1.2 [0.98--1.5]

-0.55 [0.32]

0.57 [0.31--1.1]

0.688

Daily

67 [2]

1 [0.87--1.2]

Ref

Ref

Several times a week

100 [3]

1.1 [0.96--1.2]

0.95 [0.78--1.2]

0.649

Weekly
Monthly

150 [3]
25 [1]

1.1 [1--1.2]
1.6 [1.3--1.9]

Ref
-0.048
[0.11]
-0.03
[0.098]
0.14 [0.15]

0.97 [0.8--1.2]
1.2 [0.86--1.5]

0.760
0.349

no carpets
Other
No

2 [0]
23 [0]
53 [3]

2.4 [0.046--130]
1 [0.77--1.4]
1.2 [1--1.4]

2.1 [0.85--5.4]
1.2 [0.84--1.6]
Ref

0.112
0.368
Ref

Yes
Daily

314 [6]
6 [0]

1.1 [1--1.2]
2.1 [1.1--3.8]

0.88 [0.73--1.1]
Ref

0.194
Ref

Weekly
Monthly
Yearly
Never
(Missing)
Monthly, Yearly, Never,
or no attic
Daily_or_Weekly

9 [0]
20 [0]
56 [0]
224 [6]
52 [3]

1.5 [0.98--2.4]
1.4 [1.1--1.7]
1.1 [0.9--1.3]
1 [0.96--1.1]
1.2 [1.1--1.5]

0.76 [0.48]
0.15 [0.17]
Ref
-0.13
[0.097]
Ref
-0.091
[0.28]
-0.28 [0.25]
-0.34 [0.23]
-0.44 [0.22]
-0.24 [0.24]

0.91 [0.53--1.6]
0.76 [0.47--1.2]
0.71 [0.45--1.1]
0.64 [0.42--0.99]
0.79 [0.5--1.3]

0.747
0.273
0.137
0.050
0.322

352 [9]
15 [0]

1.1 [1--1.2]
1.7 [1.3--2.4]

Ref
0.32 [0.14]

Ref
1.4 [1--1.8]

Ref
0.026

Before 2017
2017 and After

9 [0]
17 [1]

1.6 [0.97--2.6]
1.2 [0.84--1.7]

Ref
-0.17 [0.36]

Ref
0.84 [0.44--1.6]

Ref
0.643

(Missing)
No

341 [8]
183 [4]

1.1 [1--1.2]
1.2 [1.1--1.3]

NA
Ref

NA
Ref

Yes
No
don't know

184 [5]
264 [6]
5 [1]

1.1 [0.97--1.2]
1.1 [1--1.2]
1.2 [0.56--2.7]

NA
Ref
-0.014
[0.068]

0.99 [0.86--1.1]

0.831

0.44 [0.43]

1.6 [0.68--3.6]

0.302

Do you have an attic in your home?

If you have an attic in your home,
how often do you enter the attic?

Estimate
[SE]

4

Risk Factor

If yes, when was it done?

How often do you or your
child/ward remove shoes before
entering your home?

Does anyone in the home work
primarily outdoors in a job with
frequent soil or
slag contact? (slag reprocessor,
construction worker, landscaping,
etc.)

How often do they change clothing
when entering the home after work
outdoors?

Do you have a job that may bring
you into contact with lead?

Value

Number of
participants
[missing blood lead]

Geometric mean
blood lead
[95% CI]

Yes

97 [2]

1.2 [1.1--1.4]

(Missing)
No soil replaced

1 [0]
264 [6]

NA
1.1 [1--1.2]

After 2016

67 [2]

1.2 [1--1.3]

Before and during 2016

26 [0]

Other
(Missing)
Never or Seldom
Remove Shoes
Sometimes or Always
Remove Shoes

Estimate
[SE]
0.055
[0.077]

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

1.1 [0.91--1.2]

0.477

NA
Ref

NA
Ref

1 [0.88--1.2]

0.614

1.4 [1.1--1.6]

NA
Ref
0.046
[0.091]
0.068
[0.13]

1.1 [0.83--1.4]

0.599

2 [0]
8 [1]

1.3 [0.0024--710]
1 [0.58--1.8]

0.31 [0.47]
NA

1.4 [0.55--3.4]
NA

0.509
NA

189 [7]

1.2 [1.1--1.3]

Ref

Ref

176 [2]

1 [0.95--1.1]

Ref
-0.11
[0.062]

0.9 [0.79--1]

0.080

(Missing)
No
Yes

2 [0]
274 [7]
88 [2]

1.8 [0.29--12]
1.1 [1--1.2]
1.2 [1--1.3]

NA
Ref
0.2 [0.077]

NA
Ref
1.2 [1.1--1.4]

NA
Ref
0.009

(Missing)
Never do this

5 [0]
58 [3]

1.9 [1.2--3.1]
1 [0.86--1.2]

NA
Ref

NA
Ref

NA
Ref

Seldom do this
Sometimes do this
Always do this

29 [2]
36 [0]
51 [1]

1.1 [0.89--1.4]
1.4 [1.1--1.7]
1.2 [1.1--1.5]

0.11 [0.14]
0.27 [0.13]
0.3 [0.12]

1.1 [0.85--1.5]
1.3 [1--1.7]
1.4 [1.1--1.7]

0.434
0.038
0.011

(Missing)
No

193 [3]
281 [7]

1.1 [0.98--1.2]
1.1 [1--1.2]

NA
Ref

NA
Ref

Yes
(Missing)

62 [1]
24 [1]

1.3 [1.1--1.5]
1.3 [0.95--1.7]

NA
Ref
0.22
[0.075]
NA

1.3 [1.1--1.4]
NA

0.003
NA

5

Risk Factor

Do you have a job that may bring
you into contact with lead?

Have you or your child/ward used
any Mexican pottery in the past
month?

Have you or your child/ward used
any home (folk) remedies (used in
Indian,
Asian and Hispanic cultures) in the
past month for any illnesses?

Have you or your child/ward eaten
any Mexican candy (containing
chili powder or
tamarind) in the past month?

Do you or your child/ward own any
imported toy or costume jewelry

Number of
participants
[missing blood lead]
276 [7]

Geometric mean
blood lead
[95% CI]
1.1 [0.99--1.1]

29 [1]
4 [0]

1.4 [1.2--1.8]
1.8 [0.54--5.9]

Other

24 [0]

1 [0.74--1.3]

Mining

3 [0]

0.75 [0.45--1.3]

Historic
Nonoccupation
(Missing)
Don't know

5 [0]
2 [0]
24 [1]
1 [0]

1.8 [0.89--3.6]
1.7 [0.59--5.2]
1.3 [0.95--1.7]
1.5 [NaN--NaN]

No
Yes

363 [9]
2 [0]

(Missing)
Don't know
No

Value
No
Construction or
Maintenance
Mechanic

Estimate
[SE]

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

0.44 [0.1]
0.46 [0.26]
-0.067
[0.11]
-0.024
[0.29]

1.6 [1.3--1.9]
1.6 [0.96--2.6]

<0.001
0.077

0.94 [0.75--1.2]

0.547

0.98 [0.55--1.7]

0.934

0.14 [0.23]
0.26 [0.36]

1.1 [0.74--1.8]
1.3 [0.65--2.6]

0.550
0.464

1.1 [1--1.2]
1.8 [0.16--21]

0.085
[0.56]
0.4 [0.68]

1.1 [0.37--3.2]
1.5 [0.4--5.6]

0.879
0.558

1 [0]
3 [0]
345 [8]

1.1 [NaN--NaN]
1.2 [0.15--9.8]
1.1 [1--1.2]

Ref
0.11 [0.3]

Ref
1.1 [0.62--2]

Ref
0.718

Yes

14 [0]

1.2 [0.92--1.6]

0.1 [0.33]

1.1 [0.58--2.1]

0.757

(Missing)
No

5 [1]
363 [9]

1.2 [0.56--2.7]
1.1 [1--1.2]

NA
Ref

NA
Ref

Don't know

2 [0]

1.6 [0.019--130]

NA
Ref
-0.034
[0.48]

0.97 [0.38--2.4]

0.942

Yes
No
Don't know

2 [0]
294 [7]
5 [0]

1.1 [0.94--1.3]
1.1 [1.1--1.2]
0.74 [0.32--1.7]

-0.18 [0.37]

0.83 [0.4--1.7]

0.627

-0.34 [0.25]

0.71 [0.43--1.2]

0.182

6

Risk Factor
that are over
10 years old?

Do you or your child/ward have any
hobbies that may involve exposure
to lead?

Do you or your child/ward have any
hobbies that may involve exposure
to lead?

How many portions of fish and
other seafood (including shrimp)
did you or your
child/ward eat in the past week?

How many portions of rice (white
or brown) did you or your
child/ward eat in
the past week?

How many portions of chicken did
you or your child/ward eat in the
past week?

Value

Number of
participants
[missing blood lead]

Geometric mean
blood lead
[95% CI]

Yes
No

68 [2]
264 [7]

1.1 [0.91--1.3]
1.1 [1--1.2]

Yes

92 [1]

(Missing)

Estimate
[SE]

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

0.9 [0.77--1.1]
Ref

0.210
Ref

1.2 [1.1--1.4]

-0.1 [0.08]
Ref
0.17
[0.067]

1.2 [1--1.4]

0.010

11 [1]

0.81 [0.59--1.1]

NA

NA

NA

No
firearms, fishing,
hunting

264 [7]

1.1 [1--1.2]

73 [1]

gardening
Other
(Missing)
None
1-2

Ref

Ref

1.2 [0.99--1.3]

0.16
[0.074]

1.2 [1--1.4]

0.033

6 [0]
13 [0]
11 [1]
237 [7]
120 [2]

1.8 [0.93--3.5]
1.5 [0.96--2.5]
0.81 [0.59--1.1]
1 [0.95--1.1]
1.3 [1.1--1.4]

0.27 [0.23]
0.23 [0.16]
NA
Ref
0.1 [0.066]

1.3 [0.84--2]
1.3 [0.93--1.7]
NA
Ref
1.1 [0.97--1.3]

0.235
0.146
NA
Ref
0.129

3-4
None

10 [0]
200 [5]

1.5 [0.87--2.7]
1.1 [1--1.2]

1.2 [0.86--1.8]
Ref

0.262
Ref

1-2

146 [4]

1.1 [0.98--1.2]

0.21 [0.19]
Ref
0.022
[0.065]

1 [0.9--1.2]

0.734

3 or more
None

21 [0]
60 [1]

1.6 [1.2--2]
1.4 [1.2--1.7]

1.4 [1--1.8]
Ref

0.025
Ref

1-2

194 [6]

1.1 [1--1.2]

0.75 [0.64--0.87]

<0.001

3-4
5 or more

98 [2]
15 [0]

1 [0.89--1.1]
1 [0.7--1.4]

0.3 [0.13]
Ref
-0.29
[0.079]
-0.28
[0.093]
-0.37 [0.17]

0.76 [0.63--0.91]
0.69 [0.5--0.95]

0.003
0.026

7

Table E - 2: Participant Child Specific Questionnaire Results and Age-Adjusted Estimates of Association with Blood Lead,
Anaconda EI (N=71, 7 missing blood lead results)
Abbreviations: CI: Confidence Interval, NA: Not Applicable, Ref: Reference Factor Level, SE: Standard Error

Risk Factor

Value

Number of
Geometric mean
participants [missing
Estimate
blood lead
blood lead]
[95% CI]
[SE]

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

No

33 [3]

0.67 [0.56--0.8]

Ref

Ref

Ref

Yes

37 [4]

0.89 [0.73--1.1]

0.16 [0.15]

1.2 [0.88--1.6] 0.286

1 [0]

0.45

NA

NA

NA

No

64 [5]

0.75 [0.66--0.86] Ref

Ref

Ref

Yes

5 [1]

1.3 [0.64--2.6]

0.1 [0.24]

1.1 [0.68--1.8] 0.670

(Missing)

2 [1]

0.45 [NA]

NA

NA

NA

No

42 [5]

0.68 [0.59--0.78] Ref

Ref

Ref

Yes

28 [2]

0.94 [0.73--1.2]

0.25 [0.15]

1.3 [0.96--1.7] 0.110

(Missing)

1 [0]

0.45

NA

NA

Does the child put their hands or toys in their mouth? (Missing)

Have you noticed the child eating dirt while playing
outside?

Has your child ever had their blood tested for lead?

NA

Table E - 3: Adjusted Model Fixed Effects – Blood Lead
Abbreviations: NA: Not Applicable

Parameter
Intercept
Basis Spline
of age (1)
Basis Spline
of age (3)
Basis Spline
of age (3)
Sex: Male
Construction
or
Maintenance
Enter Attic:
Daily or
Weekly
Do not eat
Chicken

Estimate

Standard
Error

-0.10

0.11

-1.49

0.33

1.01

0.25

0.30

0.25

0.21

0.05

0.34

0.10

0.41

0.13

0.30

0.07

Ratio of
Geometric
Means
NA
NA
NA
NA
1.2

Degrees
of
Freedom
237.5753

t value

p value

-0.97

0.33

243.0301

-4.54

<0.01

326.7575

4.00

<0.01

322.457

1.20

0.23

205.8827

4.49

<0.01

308.1739

3.38

<0.01

326.6467

3.02

<0.01

321.637

4.10

<0.01

1.4

1.5

1.4

Table E - 4: Participant Questionnaire Results and Age-Adjusted Estimates of Association with Total Urinary Arsenic, Anaconda EI
(N=367, 13 missing urine results)

Risk Factor

What is your or your child/ward’s sex?

City

Are you or your child/ward Hispanic, Latino/a, or
Spanish Origin? (one or more
categories may be selected)

What is your or your child/ward’s race? (one or more
categories may be
selected)

Do you or your child/ward spend time outside the home
(e.g., work or
daycare/school)?
If yes, how long are your or your child/ward out of the
house during the day?

Value

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Female

194 [5]

Male

173 [8]

Anaconda

358 [13]

Bozeman or Deer Lodge

9 [0]

No

Geometric
mean
urinary
arsenic
[95% CI]
8.8 [7.8-10]

Estimate
[SE]
Ref

Ratio of
Geometric
Means
[CI]

p value
(fixed
effects)

Ref
0.79
[0.68-0.92]

Ref

Ref
0.74
[0.35-1.6]

Ref

Ref

7.4 [6.5-8.4]
8.1 [7.4-8.9]

-0.23
[0.076]

-0.3
[0.39]

355 [13]

6.8 [4.5-10]
8.2 [7.5-9]

Yes

11 [0]

6.1 [3.6-10]

-0.11
[0.26]

Ref
0.89
[0.53-1.5]

(Missing)

1 [0]

White

352 [13]
9 [0]

Ref
0.8 [0.45-1.4]

Ref

Other

Ref
-0.23
[0.3]

(Missing)

6 [0]

NA

NA

NA

No

43 [2]

Ref

Ref

Yes

324 [11]

-0.11
[0.16]

Ref
0.89
[0.66-1.2]

0 hours

36 [2]

Ref

Ref

Ref

4.7
8.2 [7.5-9]
6.6 [4.3-10]
4 [1.9-8.5]
10 [7.3-14]
7.9 [7.2-8.6]
9.4 [6.7-13]

Ref

Ref

0.002

0.443

0.667

0.442

0.471

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Geometric
mean
urinary
arsenic
[95% CI]

Estimate
[SE]

1 to 4 hours

86 [5]

8.6 [7.1-10]

-0.014
[0.19]

5 to 8 hours

79 [2]

8.5 [6.9-11]

-0.019
[0.19]

Over 8 hours

165 [4]

7.4 [6.6-8.4]

(Missing)

1 [0]

0 days

36 [2]

1-3 days per week

0.939

-0.08
[0.19]

Ratio of
Geometric
Means
[CI]
0.99
[0.68-1.4]
0.98
[0.67-1.4]
0.92
[0.63-1.3]

NA

NA

NA

Ref
0.15
[0.24]

4 or more days per week

306 [9]

7.8 [7.1-8.6]

-0.044
[0.17]

Ref
1.2 [0.72-1.9]
0.96
[0.68-1.3]

Ref

24 [2]

7
9.4 [6.7-13]
10 [6.4-16]

(Missing)

1 [0]

NA

NA

NA

Do not spend time outdoors

7 [0]

7
15 [7.8-28]

Ref

Ref

2 to 4 hours per day

150 [5]

7.8 [6.8-8.9]

-0.27
[0.35]

4 to 6 hours per day

59 [1]

7.2 [5.7-9]

-0.45
[0.37]

Less than 2 hours per day

104 [7]

Over 6 hours per day

46 [0]

8.5 [7.1-10]
8.4 [6.6-11]

-0.2
[0.36]
-0.2
[0.37]

Ref
0.77
[0.39-1.5]
0.64
[0.31-1.3]
0.82
[0.41-1.6]
0.82 [0.4-1.7]

(Missing)

1 [0]

61

NA

NA

NA

Risk Factor

If you or your child/ward are out of the house during the
day, how many times
per week?

How many hours per day do you or your child/ward
typically spend outdoors?

Value

p value
(fixed
effects)

0.919

0.668

0.537

0.798

0.448

0.221

0.583
0.589

2

Risk Factor

Approximately when was the building built?

How many hours per day do you or your child/ward
typically spend in your attic?

Does you or your child/ward wash hands before eating?

How long have you lived at this address?

Value

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Geometric
mean
urinary
arsenic
[95% CI]
8.1 [7.3-8.9]
8.6 [6.7-11]
7.2 [4.6-11]

Estimate
[SE]

Ratio of
Geometric
Means
[CI]

Ref
0.2
[0.14]
0.12
[0.25]

Ref
1.2 [0.92-1.6]
1.1 [0.69-1.9]

Ref

2.9
8.1 [7.4-8.9]
10 [6.4-17]
4.7 [3.2-7]
8.7 [7.8-9.8]
7.1 [6.1-8.2]
8.4 [4.9-15]

NA

NA

NA

Ref
0.18
[0.22]

Ref
1.2 [0.78-1.8]

Ref

NA

NA

NA

Ref
-0.11
[0.11]

Ref
0.9 [0.73-1.1]

Ref

Ref

Ref

-0.16
[0.36]
-0.12
[0.29]

NA

pre1980

287 [9]

post1980

62 [2]

Don’t know

17 [2]

(Missing)

1 [0]

Do not spend time in attic

343 [12]

Spend time in attic

16 [0]

(Missing)

8 [1]

Always

231 [3]

Never or Sometimes

136 [10]

Less than 6 months

15 [2]

6 months to less than 2 years

18 [1]

2 to 5 years

81 [1]

8.9 [5-16]
8.1 [6.7-9.7]

6 to 10 years

52 [2]

7.6 [6.1-9.4]

-0.27
[0.3]

More than 10 years

200 [7]

8.2 [7.2-9.2]

-0.31
[0.28]

Ref
0.85
[0.43-1.7]
0.89 [0.5-1.6]
0.77
[0.43-1.4]
0.73
[0.43-1.3]

(Missing)

1 [0]

10

NA

NA

p value
(fixed
effects)

0.175
0.623

0.413

0.325

0.650
0.678

0.369

0.273

3

Risk Factor

Do you speak a language other than English at home? (5
years or older)

Do you live in a(n):

Do the windows (e.g., sills) have peeling paint?

Is there peeling paint in other places such as cabinets,
interior walls and/or
exterior walls?

Any peeling paint

Value

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

No

353 [13]

Yes

11 [0]

(Missing)

3 [0]

Single Family Home
Apartment, Townhouse,
Condominium, or Other

342 [12]

Mobile Home

7 [0]

No

293 [5]

18 [1]

Geometric
mean
urinary
arsenic
[95% CI]
8 [7.3-8.7]
11 [6.5-17]
21 [0.82-560]
8.1 [7.4-8.9]
7 [4.2-11]
8.9 [3.2-25]
8.5 [7.7-9.4]

Estimate
[SE]

Ratio of
Geometric
Means
[CI]

Ref
0.14
[0.27]

Ref
1.2 [0.68-2]

Ref

NA

NA

NA

Ref
0.047
[0.28]
0.045
[0.39]

Ref
1 [0.61-1.8]
1 [0.49-2.3]

Ref

-0.21
[0.13]

0.81
[0.63-1.1]

p value
(fixed
effects)

0.600

0.865
0.909

Yes

74 [8]

No

261 [6]

6.6 [5.7-7.6]
8.4 [7.5-9.3]

Do not know

3 [0]

6.2 [2.3-16]

-0.16
[0.51]

Yes

96 [6]

-0.021
[0.12]

(Missing)

7 [1]

NA

NA

NA

No

228 [3]

7.2 [6-8.6]
13 [6.4-27]
8.6 [7.7-9.7]

0.85
[0.31-2.3]
0.98
[0.77-1.2]

Ref

Ref

Yes

133 [9]

7.1 [6.2-8.2]

-0.12
[0.11]

Ref
0.89
[0.71-1.1]

0.128

0.753

0.865

0.306

4

Risk Factor

How often do you clean your home using a wet mop?

How often do you clean your home using a vacuum
cleaner?

Do you have an attic in your home?
If you have an attic in your home, how often do you
enter the attic?

Value

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

(Missing)

6 [1]

Daily

4 [0]

Monthly

61 [1]

Other

37 [4]

Several times a week

42 [0]

Weekly

223 [8]

Daily

67 [1]

Several times a week

100 [3]

Weekly

150 [4]

Monthly

25 [1]

no carpets

2 [0]

Other

23 [4]

No

53 [2]

Yes
Monthly, Yearly, Never, No
attic

314 [11]
352 [13]

Geometric
mean
urinary
arsenic
[95% CI]
15 [6.3-35]
6.4 [3.2-13]
9 [7.3-11]
10 [7.8-14]
8.6 [6.2-12]
7.5 [6.7-8.4]
7.1 [6.1-8.1]
9.1 [7.5-11]
7.4 [6.5-8.5]
12 [7.9-19]

Estimate
[SE]

Ratio of
Geometric
Means
[CI]

NA

NA

NA

Ref
0.23
[0.49]
0.34
[0.5]
0.24
[0.5]
0.066
[0.48]

Ref
1.3 [0.49-3.3]
1.4 [0.53-3.7]
1.3 [0.48-3.3]
1.1 [0.42-2.7]

Ref

0.33
[0.17]
0.031
[0.16]
0.4
[0.24]

1.4 [1-1.9]
1 [0.76-1.4]
1.5 [0.94-2.4]
0.78
[0.18-3.4]
1.1 [0.62-1.9]

5.4 [0.6-48]
8.7 [5.7-13]
8.1 [6.3-10]

-0.24
[0.76]
0.065
[0.29]

8.1 [7.4-8.9]
7.9 [7.2-8.6]

Ref

p value
(fixed
effects)

0.636
0.502
0.629
0.890

0.052
0.844
0.092

0.749
0.821
Ref

-0.028
[0.15]

Ref
0.97
[0.72-1.3]

Ref

Ref

Ref

0.855

5

Risk Factor

If yes, when was it cleaned?

Does your home have a yard with bare dirt?

Has soil in your yard been removed and replaced with
clean soil?

If yes, when was it done?
How often do you or your child/ward remove shoes
before entering your home?

Value

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Daily or Weekly

15 [0]

Before 2017

9 [1]

2017 and After

17 [3]

(Missing)

341 [9]

No

183 [6]

Yes

184 [7]

No

264 [9]

don't know

5 [0]

Yes

97 [4]

(Missing)

1 [0]

No soil replaced

264 [9]

After 2016

67 [4]

Before and during 2016

26 [0]

Other

2 [0]

(Missing)

8 [0]

Never or Seldom Remove Shoes

189 [9]

Geometric
mean
urinary
arsenic
[95% CI]
14 [8.1-25]
9.5 [4.2-22]

Estimate
[SE]
0.54
[0.22]
Ref

Ratio of
Geometric
Means
[CI]
1.7 [1.1-2.7]

0.015

0.148

p value
(fixed
effects)

6.6 [4.9-8.9]
8.1 [7.4-8.9]
8.1 [7.2-9.2]
8.1 [7.1-9.2]
7.8 [7-8.6]
8.1 [3.7-18]
9.1 [7.5-11]

-0.66
[0.41]

Ref
0.52
[0.25-1.1]

NA

NA

NA

Ref
0.012
[0.11]

Ref
1 [0.82-1.2]

Ref

Ref
0.11
[0.67]
0.11
[0.12]

Ref
1.1 [0.3-4.1]
1.1 [0.88-1.4]

Ref

3.6
7.8 [7-8.6]
9.4 [7.5-12]
8.9 [5.9-13]
3.5 [0.73-16]
7.6 [4.4-13]
7.2 [6.4-8]

NA

NA

NA

Ref
0.16
[0.14]
0.066
[0.2]
-0.79
[0.75]

Ref
1.2 [0.88-1.6]
1.1 [0.72-1.6]
0.46
[0.11--2]

Ref

NA

NA

NA

Ref

Ref

Ref

0.909

0.874
0.383

0.276
0.747
0.299

6

Risk Factor

Does anyone in the home work primarily outdoors in a
job with frequent soil or
slag contact? (slag reprocessor, construction worker,
landscaping, etc.) (if
NO, skip to question 49)

How often do they change clothing when entering the
home after work outdoors?

Do you have a job that may bring you into contact with
arsenic?
Do you have a job that may bring you into contact with
arsenic?

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Value
Sometimes or Always Remove
Shoes

176 [4]

(Missing)

2 [0]

No

274 [10]

Yes

88 [3]

(Missing)

5 [0]

Never do this

58 [1]

Seldom do this

29 [0]

Sometimes do this

36 [3]

Always do this

51 [2]

(Missing)

193 [7]

No

291 [11]

Yes

53 [1]

(Missing)

23 [1]

No

288 [11]

Geometric
mean
urinary
arsenic
[95% CI]
9.3 [8.1-11]
2.8
[0.066-120]
8.2 [7.4-9.2]

Estimate
[SE]
0.3
[0.097]

Ratio of
Geometric
Means
[CI]
1.3 [1.1-1.6]

0.002

NA

NA

NA

Ref

Ref

p value
(fixed
effects)

7.2 [6.2-8.4]
27 [10-73]
9 [6.9-12]
6.3 [4.8-8.2]

-0.07
[0.12]

Ref
0.93
[0.74-1.2]

NA

NA

NA

Ref
-0.41
[0.21]

Ref

7.8 [6-10]
6.7 [5.6-8]
8.6 [7.6-9.8]
8.4 [7.6-9.4]

-0.19
[0.2]
-0.31
[0.18]

Ref
0.66
[0.44--1]
0.83
[0.56-1.2]
0.74
[0.52--1]

NA

NA

NA

Ref

Ref

6.7 [5.6-7.9]
7.5 [5.5-10]
8.5 [7.6-9.5]

-0.15
[0.13]

Ref
0.86
[0.67-1.1]

NA

NA

NA

Ref

Ref

Ref

0.562

0.054

0.339
0.086

0.261

7

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Mechanic

2 [0]

Geometric
mean
urinary
arsenic
[95% CI]
5.1
[0.0096-2800]

Construction or Maintenance

14 [0]

5.9 [4.5-7.7]

-0.16
[0.23]

Other

25 [0]

-0.24
[0.18]

Mining

2 [0]

6.5 [5.1-8.1]
5.4 [4.1e05-7e+05]

Nonoccupational

9 [0]

7.7 [4.4-13]

-0.059
[0.29]

Historic

4 [1]

-0.098
[0.47]

(Missing)

23 [1]

11 [1.7-65]
7.5 [5.5-10]

0.89
[0.26--3]
0.94
[0.54-1.6]
0.91
[0.36-2.3]

Don't know

1 [0]
363 [13]

Have you or your child/ward used any Mexican pottery
in the past month?

Yes

2 [0]

Ref
0.39
[0.88]
0.19
[1.1]

Ref
1.5 [0.27-8.1]
1.2 [0.15-9.8]

Ref

No

7.4
8.1 [7.4-8.9]
7.4 [7.3-7.4]

(Missing)

1 [0]

NA

NA

NA

Have you or your child/ward used any home (folk)
remedies (used in Indian,
Asian and Hispanic cultures) in the past month for any
illnesses?

Don't know

3 [0]

4
10 [0.41-250]

Ref

Ref

No

345 [11]

8 [7.3-8.8]

-0.064
[0.47]

Ref
0.94
[0.37-2.3]

Risk Factor

Value

Estimate
[SE]
-0.34
[0.63]

-0.11
[0.63]

Ratio of
Geometric
Means
[CI]
0.71
[0.21-2.4]
0.85
[0.54-1.3]
0.78
[0.55-1.1]

p value
(fixed
effects)

0.591

0.476

0.187

0.856

0.837

0.835

0.660
0.858

0.891

8

Risk Factor

Have you or your child/ward eaten any Mexican candy
(containing chili powder or
tamarind) in the past month?

Do you or your child/ward own any imported toy or
costume jewelry that are over
10 years old?

Do you or your child/ward have any hobbies that may
involve exposure to lead?

Do you or your child/ward have any hobbies that may
involve exposure to lead?

Value

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Yes

14 [2]

(Missing)

5 [0]

No

363 [13]

Don't know

2 [0]

Yes

2 [0]

No

294 [8]

Don't know

5 [1]

Yes

68 [4]

No

264 [8]

Yes

92 [4]

(Missing)

11 [1]

No

264 [8]

firearms, fishing, hunting

73 [3]

gardening

6 [0]

Geometric
mean
urinary
arsenic
[95% CI]
9.5 [6.4-14]
8.1 [3.7-18]
8.1 [7.4-8.8]
11 [4.5-25]
16 [0.065-3800]
8 [7.2-8.8]

-0.04
[0.54]

Ratio of
Geometric
Means
[CI]
0.96
[0.33-2.8]

NA

NA

NA

NA
0.014
[0.75]
0.61
[0.58]

NA
1 [0.23-4.4]
1.8 [0.59-5.7]

NA

Ref

Ref

4 [2.4-6.8]
9.1 [7.4-11]
8.3 [7.4-9.2]
7.6 [6.4-9.1]
7.8 [3.9-16]
8.3 [7.4-9.2]

-0.37
[0.41]
0.17
[0.12]

Ref
0.69
[0.31-1.5]
1.2 [0.92-1.5]

Ref
-0.15
[0.11]

Ref
0.86 [0.7-1.1]

Ref

NA

NA

NA

Ref

Ref

7.4 [6-9.1]
11 [3.5-33]

-0.16
[0.12]
-0.0079
[0.36]

Ref
0.85
[0.68-1.1]
0.99 [0.5-2]

Estimate
[SE]

p value
(fixed
effects)

0.941

0.985
0.297

0.366
0.184

0.166

0.172
0.982

9

How many portions of rice (white or brown) did you or
your child/ward eat in
the past week?

How many portions of chicken did you or your
child/ward eat in the past week?

Geometric
mean
urinary
arsenic
[95% CI]

-0.16
[0.26]
NA

NA

NA

Ref
0.77
[0.094]
0.84
[0.26]

Ref
2.2 [1.8-2.6]
2.3 [1.4-3.9]

Ref

0.17
[0.1]
0.14
[0.21]

1.2 [0.96-1.4]
1.1 [0.76-1.7]

60 [1]

7.8 [5.4-11]
7.8 [3.9-16]
6.1 [5.6-6.6]
13 [11-16]
14 [5.5-34]
7.6 [6.7-8.5]
8.8 [7.6-10]
9.1 [7.1-12]
9.1 [7.2-11]

Ratio of
Geometric
Means
[CI]
0.86
[0.51-1.4]

Ref

1-2

194 [6]

8.4 [7.3-9.5]

-0.022
[0.13]

3-4

98 [4]

7.3 [6.2-8.5]

-0.2
[0.15]

5 or more

15 [2]

6.7 [4.5-10]

-0.17
[0.28]

Ref
0.98
[0.76-1.3]
0.82
[0.61-1.1]
0.84
[0.49-1.5]

Risk Factor

How many portions of fish and other seafood (including
shrimp) did you or your
child/ward eat in the past week?

Number of
urinary
arsenic
participants
[missing
urinary
arsenic]

Value

other

13 [1]

(Missing)

11 [1]

None

237 [12]

1-2

120 [1]

3-4

10 [0]

None

200 [5]

1-2

146 [7]

3 or more

21 [1]

None

Estimate
[SE]

p value
(fixed
effects)

0.554

<0.001
0.002

0.113
0.521
Ref

0.867

0.184

0.551

10

Table E - 5: Participant Child Specific Questionnaire Results and Age-Adjusted Estimates of Association with Total Urinary Arsenic,
Anaconda EI (N=71, 7 missing blood lead results)
Abbreviations: CI: Confidence Interval, NA: Not Applicable, Ref: Reference Level, SE: Standard Error

Risk Factor

Value

Has your child ever had their blood tested for lead?

Ratio of
Geometric
Means [CI]

p value
(fixed
effects)

No

33 [3]

5.4 [4.6--6.4]

Yes

37 [5]

9.4 [7.3--12]

1 [0]

7.3

NA

NA

NA

No

64 [6]

7.1 [5.9--8.4]

Ref

Ref

Ref

Yes

5 [2]

11 [4.9--24]

(Missing)

2 [0]

5.8 [0.34--99]

NA

NA

NA

No

42 [5]

5.9 [4.9--7.1]

Ref

Ref

Ref

Yes

28 [3]

9.7 [7.3--13]

(Missing)

1 [0]

7.3

Does the child put their hands or toys in their mouth? (Missing)

Have you noticed the child eating dirt while playing
outside?

Number of
Geometric mean
participants [missing urinary arsenic Estimate
urinary arsenic]
[95% CI]
[SE]
Ref

Ref

0.27 [0.16] 1.3 [0.98--1.8]

0.29 [0.33] 1.3 [0.71--2.5]

0.26 [0.16] 1.3 [0.95--1.8]
NA

NA

Ref

0.083

0.387

0.113
NA

11

Abbreviations: NA: Not Applicable

Table E - 6: Adjusted Model Fixed Effects – Total Urinary Arsenic
Parameter

Intercept
Basis Spline
of age (1)
Basis Spline
of age (2)
Basis Spline
of age (3)
Sex: Male
Eat Seafood:
1-2
times/week
Eat Seafood:
3-4
times/week
Enter Attic:
Daily or
Weekly

Estimate

Standard Error

2.46
-2.05

0.17
0.51

0.12

Ratio of
Geometric
Means
NA

Degrees of Freedom

t value

p value

NA

246.173676
248.1026229

14.75
-4.06

<0.01
<0.01

0.38

NA

336.9649163

0.33

0.75

-0.40

0.38

NA

341.3293665

-1.06

0.29

-0.24
0.76

0.07
0.09

0.79
2.15

199.6944344
320.823082

-3.33
8.26

<0.01
<0.01

0.89

0.26

2.43

257.1397725

3.40

<0.01

0.40

0.20

1.49

337.4456251

1.97

0.05

1

Figures
Figure E - 1: Linear Mixed Effect Model Predicted Marginal Geometric Mean Blood Lead
(Chicken, Attic, Construction/Maintenance, Sex)

Figure E - 2: Linear Mixed Effect Model Predicted Marginal Geometric Mean Blood Lead (Age
+ Sex)

Figure E - 3: Linear Mixed Effect Model Predicted Marginal Geometric Mean Urinary Total
Arsenic (Attic, Eat Seafood, Sex)

Figure E-4: Linear Mixed Effect Model Predicted Marginal Geometric Mean Urinary Total
Arsenic (Age + Sex)