v>EPA
United States
Environmental Protection
Agency
Health Effects Research
Laboratory
Research Triangle Park NC 27711
EPA-600/W8-037b
June 1978
Research and Development
Human Scalp Hair:
An Environmental
Exposure Index for
Trace Elements
II. Seventeen
Trace Elements in
Four New Jersey
Communities (1972)
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U S Environmental
Protection Agency, have been grouped into nine series These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields
The nine series are
1 Environmental Health Effects Research
2 Environmental Protection Technology
3 Ecological Research
4 Environmental Monitoring
5 Socioeconomic Environmental Studies
6 Scientific and Technical Assessment Reports (STAR)
7 Interagency Energy-Environment Research and Development
8 "Special" Reports
9 Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL HEALTH EFFECTS RE-
SEARCH series This series describes projects and studies relating to the toler-
ances of man for unhealthful substances or conditions This work is generally
assessed from a medical viewpoint, including physiological or psychological
studies In addition to toxicology and other medical specialities, study areas in-
clude biomedical instrumentation and health research techniques utilizing ani-
mals — but always with intended application to human health measures
This document is available to the public through the National Technical Informa-
tion Service, Springfield. Virginia 22161
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EPA-600/l-78-037b
June 1978
HUMAN SCALP HAIR: AN ENVIRONMENTAL
EXPOSURE INDEX FOR TRACE ELEMENTS
II. Seventeen Trace Elements in Four New Jersey Communities (1972)
by
John P. Creason
Statistics and Data Management Office
Health Effects Research Laboratory
and
Thomas A. Hinners
Cecil Pinkerton
Joseph E. Bumgarner
Environmental Monitoring and Support Laboratory
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
HEALTH EFFECTS RESEARCH LABORATORY
RESEARCH TRIANGLE PARK, N.C. 27711
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DISCLAIMER
This report has been reviewed by the Health Effects Research Laboratory,
U.S. Environmental Protection Agency, and approved for publication. Mention
of trade names or commercial products does not constitute endorsement or
recommendation for use.
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FOREWORD
The many benefits of our modern, developing, industrial society
are accompanied by certain hazards. Careful assessment of the relative
risk of existing and new man-made environmental hazards is necessary
for the establishment of sound regulatory policy. These regulations
serve to enhance the quality of our environment in order to promote the
public health and welfare and the productive capacity of our Nation's
population.
The Health Effects Research Laboratory, Research Triangle Park,
conducts a coordinated environmental health research program in toxicology,
epidemiology, and clinical studies using human volunteer subjects.
These studies address problems in air pollution, non-ionizing
radiation, environmental carcinogenesis and the toxicology of pesticides
as well as other chemical pollutants. The Laboratory participates in
the development and revision of air quality criteria documents on
pollutants for which national ambient air quality standards exist or
are proposed, provides the data for registration of new pesticides or
proposed suspension of those already in use, conducts research on
hazardous and toxic materials, and is primarily responsible for providing
the health basis for non-ionizing radiation standards. Direct support
to the regulatory function of the Agency is provided in the form of
expert testimony and preparation of affidavits as well as expert advice
to the Administrator to assure the adequacy of health care and surveillance
of persons having suffered imminent and substantial endangerment of
their health.
These data are provided for those researchers interested in developing
a reliable and easily collected index of environmental exposure to certain
trace elements, and as well, the data shed light on the influences of
personal covariates on the trace element content of hair. These data are
timely with regard to the current concerns regarding low-level environmental
exposure to trace elements and their uptake by exposed populations.
F. G. Hueter, Ph. D.
Acting Director,
Health Effects Research Laboratory
iii
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ABSTRACT
Seventeen trace elements - arsenic (As), barium (Ba), boron (B),
cadmium (Cd), chromium (Cr), copper (Cu), Iron (Fe), lead (Pb), lithium
(Li), manganese (Mn), mercury (Hg), nickle (Ni), selenium (Se), silver
(Ag), tin (Sn), vanadium (V), and zinc (Zn) - were measured in human scalp
hair collected in four eastern New Jersey communities. Of the seven for
which dustfall trace element measurements were available (lead, nickle,
cadmium, copper, zinc, chromium and manganese) lead, nickle and manganese
showed significant positive relationships with children's scalp hair
concentrations. This result supports findings of an earlier New York City
study, even though the dustfall trace element concentrations are much lower
in this study. When all 17 trace elements were tested for geographic
differences, all except boron and silver showed significant differences for
children, while 8 of 17 showed significant variation in adults. Several
hair-related covariates were assessed for possible influences on scalp hair
trace element levels for both children and adults. These covariates are
evaluated as potential confounding factors in any future use of hair as
an environmental index.
IV
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CONTENTS
Foreword iii
Abstract iv
Tables vi
Acknowledgment viii
1. Introduction 1
Hypotheses 2
2. Methods 4
Environmental Monitoring 4
Scalp Hair and Covariate Information 4
Chemical Analysis 5
Statistical Analysis 6
3. Results 8
Study Population Characteristics 8
Scalp Hair Trace Element Characteristics 10
Pollution Media Trace Metal Characteristics 11
Hair Trace Element Concentrations in
Relation to Hair-Related Covariates 12
Hair Trace Element Concentrations in Relation
to Environmental Exposure, Area of
Resistance, and Personal Covariates 14
The Correlation of Housedust Trace Element
Levels with Scalp Hair Levels in Ridgewood 17
4. Summary and Discussion 19
References 47
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TABLES
Number Page
1 Sample Preparation and Analytical Methods 25
2 Number of Participants by Age, Sex, and Area of
Residence 26
3 Demographic Characteristics of Adults 27
4 Hair Color by Age Category and Sex 28
5 Hair Preparation Usage in Adults by Sex 29
6 Frequency of Haircut and Hair Shampoo by Age Category
and Sex 30
7 Length of Hair by Age Category and Sex 31
8 Length of Hair by Fequency of Shampoo for Children 32
9 Trace Element Levels in Human Scalp Hair (pg/g) 33
10 Trace Element Levels in Human Scalp Hair in Children
(ages 0-15) and Adults (ages > 16) (pg/g) 34
11 A Significance Table for Hair Element/Element Correlations. ... 35
12 Dustfall Trace Element Means by Community (mg/m2/mo.) 36
13 Housedust Trace Element Arithmetic and Geometric
Means in Ridgewood (pg/g dust) 37
14 Tests of Significance of the Effect of Hair-Related
Factors on Children's Scalp Hair Trace Element Levels 38
15 Tests of Significance of the Effect of Hair-Related
Factors on Adults' Scalp Hair Trace Element Levels 39
16 Tests of Significance of the Effect of Selected
Factors on Scalp Hair Trace Element Levels,
Using (1) Dustfall as a Measure of Environmental
Exposure and (2) Area of Residence 40-41
17 Arithmetic Mean Trace Element Concentrations in
Children's and Adults' Scalp Hair by Community
for Scalp Hair Elements with Significant
Differences Between Communities (pg/g) 42
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Number Page
18 Mean Trace Element Concentrations in Dustfall and
Scalp Hair, by Community, for Scalp Hair Elements
with a Significant Dustfall Exposure Effect 43
19 Geometric Means of Scalp Hair Trace Elements
Significantly Related to Age, by Age and Sex
(ug/g) 44-45
20 Correlations of Housedust Trace Elements to Scalp
Hair Trace Elements in Ridgewood (n=18 to 21) 46
vii
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ACKNOWLEDGEMENT
We gratefully acknowledge Ms. Peggy Stewart, Dr. Anna Yoakum, and the
personnel of Stewart Laboratories Inc., Knoxville, Tennessee, for their major
contributions and dedication to this study.
viii
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SECTION 1
INTRODUCTION
Human scalp hair has been shown to reflect increased environmental
exposure to elements such as lead, mercury, cadmium, vanadium, barium, and
arsenic (1-7). Hair chromium and zinc concentrations have been reported to
reflect deficiency conditions in humans (8-17). Similar trends for these
and other elements have been found in animal studies (8,10,14,15,18).
Scalp hair is an almost ideal test object for such population sampling;
it is painlessly removed, normally is discarded and is easily collected
and conveniently stored (1-3,10).
The purpose of this study is to support and extend findings of a
similar study carried out in greater New York City during the same relative
time period (1). A relationship had been indicated in the prior study
between values for some trace elements in scalp hair and important personal
covariates such as age, sex, and socioeconomic level. In addHion,
questions were raised concerning the effect of personal grooming and
hygiene factors on the trace element content of scalp hair. Information
was collected about these factors in an attempt to answer those questions.
Because smoking has been implicated as an important exposure covariate
for some elements (19,20), it is also included in the study. A knowledge
of the effects of the above-mentioned covariates, as well as other personal
covariates on results of analyses for trace elements in scalp hair, will
permit a more accurate assessment of the quantitative relationships
between such data and environmental exposure.
The following 17 elements will be dealt with in this report: arsenic
(As), barium (Ba), boron (B), cadmium (Cd), chromium (Cr), copper (Cu),
1
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iron (Fe), lead (Pb), lithium (Li), manganese (Mn), mercury (Hg), nickel
(Ni), selenium (Se), silver (Ag), tin (Sn), vanadium (V), and zinc (Zn).
The specific hypotheses tested in this study are:
1. Significant relationships exist for trace element concentrations
between the two "media indexes": dustfall and household dust
(housedust).
2. There are significant variations in the concentrations of selected
trace elements in scalp hair that can be attributed to personal
covariates such as age, sex, hair color, hair cosmetic treatments,
socioeconomic status, and smoking habits.
3. Environmental exposure, as measured by one of the above media
(hypothesis 1), is significantly related to the concentrations of
selected trace elements in scalp hair, even after adjusting for any
effects caused by personal covariates.
Although it is of great interest, one covariate - race - could not be
evaluated. Only four of the 325 respondents were nonwhites. This covariate
will be examined in later studies.
In addition to the above specific hypotheses, the distributional
characteristics of each scalp hair trace element, including baseline levels,
ranges, and skewness of the distributions, are also examined.
Dustfall has been used as an index of environmental exposure to trace
substances (21,22). More intimate indexes to trace substance exposure—such
as household dust, soil and water from CHESS -participant homes—have
CHESS stands for Community Health and Environmental Surveillance System
(23).
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already been considered (1,20,23). Seven metals (Cd, Cr, Cu, Pb, Mn, Ni,
and Zn) were measured in dustfall in the communities under study. All 17
elements were measured in housedust samples collected from one of the four
communities in order to examine the relationship between this index of
exposure and scalp hair trace element levels.
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SECTION 2
METHODS
Environmental Monitoring
Four eastern New Jersey CHESS communities were selected for
community-wide sampling of scalp hair: Ridgewood, Fairlawn, Matawan, and
Elizabeth. These were communities for which the general pollution exposure
gradient was believed to range from low (Ridgewood) to intermediate
(Fairlawn and Matawan) to high (Elizabeth). However upon examination of
exposure measurements of total suspended particulates, dustfall, and
gaseous pollutant data and examination of estimates of past levels, it
appears there is little reason to assume the existence of a present or past
exposure gradient for these pollutants within the four New Jersey
communities (25).
Atmospheric studies including dustfall measurements were made at CHESS
air monitoring sites. The locations of these sites were such that the
families from each of the three communities of interest were within 2.5 km
of its monitoring site.
Data on dustfall were obtained monthly for 14 months (August, 1971
through September, 1972) at the central site within each community. Standard
procedures of collection were followed (26). Housedust samples were
obtained from 14 households in the Ridgewood community by collecting the
contents of vacuum cleaner dust bags from community homes.
Scalp Hair and Covariate Information
In the spring of 1972, letters giving information about the proposed
trace element study were sent to all families actively participating in a
CHESS Acute Respiratory Disease Study (ARD) in the four communities.
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These letters included for each family member a return-addressed postpaid
envelope, with the individual member identification label affixed to the
back, and instructions for collecting the hair sample.
In the instructions it was stressed that the hair should be from the
next normal haircut or trim, and that as much hair as possible should be
collected. It was also stressed that there was no special need to wash
or shampoo the hair before the haircut or trim, because it would be washed
in the laboratory before analysis. Polyethylene bags for hair samples were
sent with the letters and had an identification label on the back, with
each person's first name, family name, and a space for the date of the
haircut. In addition, information as to frequency of haircut, place of
haircut, use and type of hair coloring preparation (dye, tint, or shampoo),
natural hair color, frequency of shampoo, and hair length was obtained
during a regular ARD study telephone interview. All of this information
was then combined with the CHESS ARD background information questionnaire
obtained at the start of the ARD study to make a complete covariate
information file on each contributing family member.
Chemical Analysis
Dustfall samples were acid extracted and the metals determined by
atomic absorption spectrophotometry (26). Housedust samples were sieved
through a 0.5-mm screen for 5 minutes at 260 oscillations per minute on a
mechanical shaker and extracted with nitric acid (6 mol/liter) at 50° C in
a muffle furnace. Hair specimens were washed with a detergent solution,
rinsed, and dried according to the procedure of Harrison et al. (27). The
sample was prepared for analysis by combustion in oxygen for some elements
and by dry ashing for others, as indicated in Table 1. The dry ashing
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procedure consisted of wetting the hair with quartz-distilled sulfuric acid
and heating at 550°C in a muffle furnace. To prevent any losses when
volatile elements were to be analyzed, weighed portions of the washed
and dried hair were prepared by the Schoniger flask technique (28).
Table 1 also shows the analytical methods used for each element.
Standard laboratory quality-control procedures were used. In addition,
recoveries of all 17 elements added to a housedust sample and to a hair
sample were evaluated by using additions that were either twice the
detection limit or twice the endogenous level, whichever was larger.
Recovery rates exceeded 85% in all cases and were greater than 95% in
most cases.
Statistical Analysis
Before statistical analysis of the data for hair, the values were
edited for outliers, values so far removed from the main body of readings
as to warrant their removal from the population for statistical analysis
purposes.
A statistical procedure was developed for this process, so that the
editing was completely objective. In this procedure the inherent population
variability, as measured by the standard deviation of the logarithms of
the values, was estimated from the central section of the sample. Limits
were then set at three standard deviations from the mean of the logs.
Histograms of the data were carefully examined to ensure the effectiveness
of this procedure, and to verify that a large number of seemingly valid
observations were not being eliminated. The percent rejected ranged from
OX for many elements to 11% for Se. Logarithms of the concentration values
were used to normalize the data and to make significance tests valid.
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Standard statistical techniques of correlation and multiple linear regression
were then used to discover the effects and interrelationships of all of the
measured variables.
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SECTION 3
RESULTS
Study Population Characteristics
Approximately 1200 families, totaling 6451 individual members, were
contacted for participation in this study through an existing CHESS sampling
network (24); 139 families responded to the hair study letter in some
fashion. Family members who gave no hair, who gave an insufficient quantity
of hair, or who gave no covariate information, were excluded. The
resultant population consisted of 325 individual subjects with fairly
complete information. The distribution of subjects by age, sex and
residence is shown in Table 2. The study population is seen to consist of
two distinct age groups. This is a result of the method of contact in the
ARD study, wherein only families having children in elementary schools
were selected. This population division presents no difficulty, however,
since subsequent analyses are made on children and adult populations
separately.
The distributions of parents with respect to smoking habits (Table 3)
reveals that a significant shift in smoking patterns occurred in moving from
the original population to the subpopulation of families donating hair
samples, and again in moving from this subpopulation to the subpopulation
of parents who actually donated their own hair. There are many more
nonsmokers and exsmokers and fewer smokers in the final population. The
smoking patterns were found to be consistent across areas for families
in which at least one member donated hair, but when the parents who
donated hair samples were examined separately, significant variations in
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smoking patterns were found (Table 3). Ridgewood parents had fewer smokers
and Elizabeth had a greater number of smokers than the other areas. This
difference in smoking patterns could be a reflection of socioeconomic
differences across areas (Table 3); Elizabeth was found to have significantly
fewer families with education of the head of household greater than high
school, a result in agreement with findings in the study of the original
population from which our subpopulation was drawn (25).
Reported hair color by sex for children (15 years of age and less) and
adults (over 15 years of age) showed significant differences in hair color
distribution between adult males and females, but not between male and
female children (Table 4). The adult males showed a higher percentage of
grey and white hair, while adult females had a higher percentage of subjects
with brown hair. These differences may be explained by looking at hair
preparation usage in adults (Table 5). There are many more females
reported as using a dye, tint, or hair coloring shampoo than there are
males. There were no children reported as using a hair coloring preparation.
As expected, males were found to have more frequent haircuts than females
in both the children and adult groups; however, a significant difference
in shampoo frequency between males and females was found only in the adults
(Table 6). Again as expected, males and females displayed different patterns
of hair length for both children and adults (Table 7). The females had much
greater frequency of shoulder length hair and longer. This was especially
true of the female children.
No relationship was found between hair length and frequency of shampoo
in adults, but a significant interaction between these variables was found
in both the male and female children (Table 8). For both sexes, there was
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a significant shift towards reduced frequency of shampooing as hair length
increased.
Scalp Hair Trace Element Characteristire
The 17 trace elements in this study all have a log-normal type of
distribution typical of trace elects in hair (1,29-33). Analytical hair
values obtained are shown in Table 9. They generally agree with published
values.
One exception to this agrees is the average scalp hair zinc
range of ,51-220 pg/g reported in some plications (8,27,29,34) and they
are lower than the average rates found in the New York study (1). However
other investigators have reported mean values between 75-197 ug/g (35)
82-190 ug/g (46), and 88-180 „„, (9). Available evidence does not support
the hypothesis that zinc was lost from our hair specimens. First,
nonionic detergent removed little, if any, Zn from hair specimens (27,37).
Second, hair specimens stored for several decades have exhibited typical
values with (30) or without (38) laboratory washing. Third, treatments
that do remove zinc from hair also remove Cu (39) or Pb (40) extensively
our values for Cu and Pb agree well with values reported in the literature.
The interrelationships of scalp hair trace metal levels were examined
separately for children (15 years of age or less) and adults (over 15 years
of age), since children are in a rapidly developing stage of growth in
contrast to adults, who have reached a leveling off ,„ 9rowth and develop,ent.
In addition, the use of hair coloring preparations by adults could possibly
affect trace element levels. Some adults also are likely to have been
exposed to some work-related sources of trace metals, and hence may display
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a good degree more variability from person to person in scalp hair trace
element burden.
It was found that children have significantly higher mean scalp hair
levels than adults for Cd, Pb, Ag and V, while Sn was significantly higher
in the adults (Table 10).
Pairwise correlation coefficients were computed separately for the
adults and children groupings using the logs of scalp hair trace metals.
There were 75 significant correlations for adults and 90 for the children
out of the 136 correlation coefficients (Table 11). Arsenic and Se were the
only elements to show consistently significant negative correlations to the
other elements. This result for Se is in close agreement with the
New York Study, whereas As was not examined in that report. Lead, Cd, Cu
and Zn were highly intercorrelated in children (r=0.5 to 0.8). In adults
these four metals were in general still highly intercorrelated, (r=0.4 to
0.7) but not as strongly as in children.
Pollution Media Trace Metal Characteristics
Arithmetic means of dustfall trace element concentrations for Pb, Cd,
Cu, Zn, Cr, Ni and Mn by community and geometric means for all 17 trace
elements in housedust from 14 houses in Ridgewood are given in Tables 12
and 13, respectively. The above seven elements were the only determinations
done on dustfall, and Ridgewood was the only community in which housedust
was collected. A previous study of gaseous and particulate pollution from
the dustfall sites failed to establish a definable gradient in pollution
exposure, and this conclusion is supported by the dustfall trace element
analysis (25). Of the seven metals measured, only Pb showed significant
differences across communities, with Fairlawn and Elizabeth higher than
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Ridgewood and Matawan. There are no data available for the other ten
elements in this study. These tables demonstrate the lack of concentration
gradients across communities as well as the similarities and differences in
trace element patterns in these media. Cd, Cr and Ni generally have much
lower concentrations than Cu, Pb, Mn and Zn in both dustfall and housedust
in all communities where measurements are available. This is in exact
agreement with the earlier New York City study.
Hair Trace Element Concentrations in Relation to Hair-Related Covariates
The possible influences of hair color, hair length, frequency of haircut,
and frequency of shampoo were assessed separately for children (<_15 years old)
and adults (>. 16 years old). In the adult groups, "hair preparation usage" is
included as one hair color category for analysis purposes. The covariates
usually have quite different distributional patterns between sexes. A
separate analysis of each covariate is carried out for each sex-age group
category in order to avoid the confounding of covariate effects with sex
differences. The results of the linear model analysis of each covariate
are presented in one table for each sex-age group in order to allow
comparisons of significant factors for each trace element (Tables 14-15).
For the children, the only covariates that are repeatedly significant
across trace elements are shampoo frequency and hair length.
Haircut frequency is significant for 2 trace elements in male children
(Ba, and V) and is never significant in females. Hair length is also
significant for Ba in male children, and the trends are the same as for
haircut frequency. That is, Ba concentrations increase with hair length and
with lessened haircut frequency. Vanadium increases with lessened haircut
frequency but displays no trends in relation to hair length.
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Hair color is a significant factor for Pb and Cd in female children's
scalp hair. In these two cases the blondes have higher levels than the
brown-haired females, quite likely as a result of the fact that the very
young females were almost all blondes. The New York study found the very
young having much higher trace element concentrations in their hair (1).
The hair color effect is quite possibly a reflection of this fact for these
two elements. Therefore in children's scalp hair, hair length and shampoo
frequency are important covariates for many of the trace elements, while
haircut frequency and hair color are not significant contributors to
observed differences, with the possible exception of haircut frequency on
vanadium in males. In subsequent analyses, therefore, only hair length and
shampoo frequency will be included as covariates.
In male adults, 7 significant trace element-covariate relationships
were found out of 68 tested with 5 of the 7 involving either haircut
frequency or hair length (Table 15). Vanadium increases with lessened
haircut frequency as it did in the male children, while Cu and As decrease
with lessened haircut frequency. Ag and V concentrations both increase with
length of hair in the adult males. Shampoo frequency is never significant,
and hair color is significant for As, and Cd. The female adults have no
significant covariate relationships.
The paucity of significant relations of shampoo frequency and hair
color to trace elements in adults leads to the conclusion that these factors
are not important determinants of scalp hair trace element levels in this
age group. Also, since hair length and haircut frequency seem to be
measuring the same effect in adults, only hair length will be included
as a covariate in subsequent analyses for this age group.
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Hair Trace Element Concentrations in Relation to Environmental Exposure.
Area of Residence, and Personal Covarlates
For each age group, a linear multiple regression analysis is used to
examine the relation of environmental exposure (as measured by dustfall
trace element content) to hair trace element content for the seven elements
measured in dustfall. The linear models for each age group include age,
sex, socioeconomic level (as measured by education of head of household),
hair length, shampoo frequency (in children only), and smoking patterns
(in adults only) as covariates, along with dustfall trace element levels.
The logs of both the scalp hair and dustfall trace element levels are used
in the analyses to make the scalp hair values more closely fit a normal
distribution and to help insure the fit of a linear model to the data.
The results of the statistical tests when monthly average trace element
dustfall rates are used are given in Table 16. Dustfall trace elements
are significantly related to hair levels for Pb, Cr, and Ni in children,
while none of the seven elements are significant for adults. Lead and Ni
show an increase in scalp hair trace clement concentration with the dustfall
gradient, while Cr shows a decrease with increasing dustfall trace element
levels (Table 10). The Pb and Ni results for children are in exact
agreement with the earlier New York study (1). Scalp hair chromium was
also significant in the previous study, but showed a general positive
relationship to media indices of pollution, while in this study that
relationship is negative for the only index available-dustfall. The
results for adults are also in agreement with the New York study, except
for the case of scalp hair Pb, which was significantly related to Pb in
dustfall in New York but is not related in this study. This lack of
14
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relationship could possibly be a result of the smaller gradient of exposure
encountered in the New Jersey communities.
There was no environmental index of exposure available for 10 of the 17
elements measured in scalp hair. The community-to-community variability of
scalp hair trace element levels was investigated for these elements as well
as for the original seven. In children, all the elements except B and Ag
indicated significant differences between communities after adjusting for
the covariates, while in adults 0 of the 17 elements showed significant
coinniunity-to-cominunity variation (Table 16). Of the 15 trace elements
found to have significantly different scalp hair concentrations across
communities in children, all except As, Li, and Se had the highest scalp
hair concentrations in Ridgewood or Elizabeth (Table 17). Ridgewood had
the highest or second highest scalp hair concentration in 13 of the 15
significant cases, and Elizabeth was highest or second highest in 8 of the
15 cases. These geographic differences indicate that there may be varying
degrees of exposure to these trace elements through some as yet
undetermined mechanisms within the communities.
Significant trends of scalp hair B, Ba, Cu, Li, Pb, Mn, Sn, V and Zn
with age were found in children, while As and B in scalp hair were related
to age in adults. In children, scalp hair Pb, Sn and V decreased with age
while B, Ba, Cu, Li, Mn, and Zn increased with age. In adults, both As and
B decreased with age. When the means of the significant trace elements
are computed by age for each sex, it is found that the age trends are
concentrated in the females for both adults and children (Table 19). For
children, the age trends are strongly evident for females but not males
in Ba, Cu, Pb, Mn, and Sn, while Zn, was the only element with a strong
15
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age trend in males but not females. For B, Li, and V the age trends were
not strongly evident in either sex when the unadjusted means were
calculated by age. For adults, the age trends in both As and B were
found to be in the females but not in the males.
For adults, significant differences in scalp hair trace elements
between sexes, after adjusting for differences in hair length, were found
for As, Ba, Cd, Hg, Pb, Mn, and Ni. For children, significant differences
between sexes, after adjusting for differences in hair length and shampoo
frequency, were found for Ba, Pb, Mn, Ni, and Sn. In both adults and
children, female scalp hair trace element concentrations were always
higher than male concentrations wherever significant differences were
found, with the exception of Pb, which was higher in males in both age
groups.
Uhen hair length and frequency of shampoo were omitted from the above
models, differences due to sex were found for every element except B, Li,
Se and Zn in children and for every element except Cr, Fe, Li, Mn, Se and
Zn in adults. Therefore, differences in many scalp hair trace element
concentrations previously attributed to sex are seen to be accounted for
by differences in scalp hair length and/or frequency of hair shampooing.
Scalp hair Cu in children in the 'area of residence1 model was the only
trace element found to be significantly related to socioeconomic (SE) level
as measured by education; Cu was not significantly related under the
dustfall model. Hence, in this study no consistent relationship to SE level
was found for any of the 17 trace elements studied.
Hair length was a significant factor in scalp hair trace element
levels for Ba, Cd, Cr, Cu, Pb, Ag and V in children. In every case
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it was marginally (a=0.04) related, so that this trace element's relation
to hair length in adults is at best tentative.
Shampoo frequency was included as a covariate for children only, and
was found to be significantly related to 8 of the trace elements: As, Cd,
Cr, Hg, Pb, Mn, Ni, and Sn. Trace element concentrations in scalp hair
increased with increased frequency of shampooing for all the above elements
except As, for which scalp hair concentrations decreased with increased
shampoo frequency.
Smoking was included as a covariate for adults only, and was found to
be significantly related to Cd (a=0.03) in the 'areas' model but not in the
dustfall model. This lack of consistency for Cd indicates that any
statement of results relating Cd in scalp hair to smoking patterns in adults
would be in the realm of speculation.
The Correlation of Housedust Trace Element Levels with Scalp Hair Levels in
Ridgewood" ~~~~~~
Housedust was collected in 14 households in Ridgewood, and trace element
levels measured for 17 elements. Of the 14 households, 9 also had at
least one member contribute a hair sample, with a total of 21 individuals
in the 9 households contributing scalp hair samples for analysis. The
correlation of these scalp hair trace elements and the corresponding
housedust trace elements gives a more direct comparison of environmental
exposure and scalp hair levels of trace elements, although other covariates
must of necessity be ignored. The relatively small sample size and the
multiple samples from within these 9 households must also be taken into
consideration in the interpretation of these correlations.
Correlations between scalp hair trace element levels and housedust
levels as well as between the logs of these variables were computed (Table
17
-------
20). Significant correlations were found for Pb and Ni using trace element
concentrations and the logs of these concentrations, while Hg and V were
significant for concentrations only and Ba for logs of concentrations only.
All significant correlations were positive. The Hg correlation was
attributable to one particular household in which very hiqh housedust Hg
was found, and in which two of the four members measured had some of the
highest observed scalp hair Hg values (1.2 and 1.9 yq/g) of the 21
individuals in the sample. The V result was not due to such a familial
relationship, however, since the correspondence between V in scalp hair and
V in housedust for both the original values and the log-transformed values
was fairly consistent across all 21 subjects. The correlation after taking
logs was still high (r=0.28) although not significant.
-------
SECTION 4
SUMMARY AND DISCUSSION
Other studies have illustrated trace element changes in hair when
exposure differences have been dramatic (2-7), while a study recently
conducted in New York City has indicated that hair trace element content
can reflect exposure trends within a single metropolitan area when there
are substantial environmental gradients between communities (1). This
report supports the New York study findings of significant effects of Pb
and Ni concentrations in children's scalp hair, using dustfall trace
element concentrations as an environmental index. Five other trace
elements for which dustfall trace element concentrations were available
(Cd, Cu, Zn, Cr and Mn) showed no significant positive relationships,
a result in agreement with the New York study except for Mn, which showed a
significant positive relationship in the earlier study. The much smaller
dustfall gradients of these trace elements across the New Jersey
communities than found in the New York study makes the Pb and Ni scalp
hair results even more striking.
No environmental index of exposure was available for 10 of the 17
elements measured in scalp hair, so that only regional variations could be
examined. Of the 17 elements studied (As, Ba, B, Cd, Cr, Cu, Fe, Pb, Li,
Mn, Hg, Ni, So, Ag, Sn, V, and Zn), all except B and Ag indicated
significant differences between communities for children, while 8 of the
17 showed significant community-to-community variation in adults. Two
of the communities (Ridgewood and Elizabeth) consistently displayed
the highest scalp hair values. These geographic differences indicate
19
-------
that there may well be varying degrees of exposure to trace elements
through some as yet undetermined biologic pathways within the communities.
Differences in content along hair fibers have been reported (4,10,11,
41-43). Consequently, efforts were made in this study to determine
whether several hair-related covariates were influencing trace element
concentrations in scalp hair. Hair color, hair length, frequency of
haircut, and frequency of shampoo were assessed for possible influences
on scalp hair trace element levels for both children and adults. A
separate analysis was carried out for each sex category in order to avoid
the confounding of covariate effects with sex differences. Hair length
and shampoo frequency were found to be important covariates in children
for many of the trace elements, while haircut frequency and hair color
were not significant contributors to observed differences in scalp hair
trace element content.
Five of the 7 significant trace element-covariate relationships,
out of 68 tested in adult males, involved either haircut frequency or
hair length. Adult females had no significant hair-related covariates.
Hence, it appears that in adults, hair-related covariates are not as
important as in children, although haircut frequency and/or hair length
could be an influencing factor on scalp hair trace element concentrations.
In examining the results of these analyses, one should keep in mind
the strong yet complex interrelationships of haircut frequency, hair
length, and shampoo frequency. Significant differences found for one
factor could be merely a reflection of that factor's interrelationship
with another factor, expecially in children.
Even with this reservation, it is interesting to note that for the
20
-------
elements for which hair length was significantly associated with scalp
hair concentrations in children (Ba, Cd, Cr, Cr, Pb, Ag and V), and in
adults (Cd and Pb) concentrations were higher with increased length of
hair in every single case. Shampoo frequency was significantly related
to As, Cd, Cr, Hg, Pb, Mn, N1 and Sn, with scalp hair concentrations
increasing with increased frequency of shampooing for all elements
except As, which had the reverse trend.
Sex was found to be a very important covariate in this study, as it
was in the New York study, especially in adults. However, in this study
it was found that in children and adults hair length and/or shampoo
frequency explained a great number of the differences attributed to sex
in the earlier study. For adults, differences in scalp hair concentrations
between sexes were found for As, B, Cd, Hg, Pb, Mn, and Ni, while in
children differences were found Ba, Pb, Mn, Ni, and Sn. Female scalp hair
concentrations were higher than male concentrations in every case except
Pb, which was higher in males in both age groups. This reversal of the
general sex trend for Pb was also noted in the New York study, and could
be a reflection of work-related exposure for the adult males. Other
investigators have found sex differences as observed in this study, with
females most often higher than males (4,8,29-33,40). The tendency for
female hair to be higher than male hair in many elements may be related
to a higher average inorganic content for hair from females (44,45).
Children (ages 0-15) had significantly higher mean scalp hair levels
than adults (ages 16+) for Cd, Pb, Ag, and V while Sn was significantly
higher in adults. This pattern of differences is exactly duplicated in
the New York study mentioned previously (1).
21
-------
Significant trends of scalp hair B, Ba, Cu, Li, Pb, Mn, Sn, V and Zn
with age were found in children, while As and B were related to age in
adults. In children scalp hair Pb, Sn and V decreased with age and the
others increased, while in adults both elements decreased with age. The
trends for scalp hair Pb, Ba and Mn in children agree with the New York
study (1). The trends for As and B with age in adults were not found in
the previous study, while trends not found here in Cu and Ba were found
there. It was found upon examination of age trends by sex that the age
trends are concentrated in the females for both adults and children.
Zn was the only element with a strong age trend in males but not females.
The causes .of these age trends are not yet clearly understood.
Smoking in adults and socioeconomic level in both adults and
children were not found to be strongly associated with any scalp hair
trace element concentrations.
Housedust trace element measurements in Ridgewood from 9 homes (with
21 total hair samples) provided the opportunity for a very limited
examination of the relationship of this media index to scalp hair trace
element levels.
Significant relationships were found for Pb, Ni, Hg, V and Ba, with
Pb and Ni being the only trace elements significant both before and after
log-transforming the data. All significant correlations were positive.
The Pb and Ni results agree with those found in the New York study.
The hair element intercorrelations (Table 11) show agreement with
several element intercorrelations reported for other human tissues.
Schroeder et al. (46) reported that Cr was significantly correlated with
Ba, Mn and Ni in 14 to 18 of the 29 human tissues examined. Ba and Mn
correlated in 15 of 28 tissues in another report (47). In our data, hair
22
-------
The highly significant correlations in hair between Cd, Cu and Pb have
been found by other investigators (30-32). As in the New York study (1)
and another study (31), hair Se (a nonmetal) showed a negative correlation
with certain hair elements. Hair As (a nonmetal), which was not examined
in the New York study, was the only element besides Se to show significant
negative correlations with other trace elements. The Fe - V correlation
in hair is interesting in view of evidence that V, like Fe, is bound to
transferrin in blood (49) and that hemoglobin and tissue respiration are
decreased in vanadium toxicity (50).
External contamination may account for the high proportion of
outliers (11%) found in this study for Se. This Se phenomenon was also
observed in the New York study, with 7.6% outliers. The use of special
shampoos containing Se increases hair Se content significantly (30,51).
Also, Bate (39) has shown that Se when added externally to the hair was
resistant to removal by a variety of washing procedures.
Laboratory washing of hair before trace element analyses has been a
point of contention (3,4,9,10,33,37,39,40,43,52-56). After comparing
five techniques, the washing procedure described by Harrison et al. (27)
was selected for use in this study. The detergent used in this procedure
was demonstrated to be similar in effect to commercial shampoos, which
agrees with the findings of Bate for nonionic detergents (52). In an
earlier UPA hair study (2), a metal chelating agent (EDTA) was Included in
the hair washing procedure, but use of this reagent was not recommended
in a followup report (3), and other investigators have agreed (37,57).
Dilute acid effectively removes metals from the hair (40).
The relationship between metal content of hair and (a) content in other
23
-------
tissues and (b) metabolic status are separate and complex issues, which
should not be confused with the exposure relationships that are demonstrated.
Some evidence indicates that trace element content of hair can reflect whole
body content (11,58-60) or content in specific tissues (4,10,11,14-16,59-62).
When values for hair do not reflect values for tissues (10,29,63,64), hair
may reflect the metabolic or health status (10,12,14,18,62) while the blood
and other tissue values may not (10,18,20,63-70).
The absence of a demonstrable relationship between hair content and
media values for some elements in this study is not definitive, but may
simply indicate that:
(a) the exposure difference was not sufficient for a correlation
effect on hair trace metal levels to be observed or
(b) that the media indices employed were not representative of the
overall metal exposure for the population sampled.
Future hair reports on other geographic areas will help to further
clarify the utility of scalp hair as a community exposure monitor.
24
-------
TABLE 1. SAMPLE PREPARATION AND ANALYTICAL METHODS*
Metals Preparation Analysis*
Cd.Pb Oxygen combustion AA aspiration
Cu,Mn,Zn,Fe Oxygen combustion AA aspiration
As.Hg.Se Oxygen combustion AA on vapor
Li Oxygen combustion Flame Photometry
Ag Oxygen combustion ES
Ba.B.Cr Dry ashing ES
Ni.V.Sn Dry ashing ES
* AA = atomic absorption
ES = emission spectroscopy
+ Manganese in hair was evaluated from ES data when detection from AA
was found to be inadequate.
25
-------
TABLE 2. NUMBER OF PARTICIPANTS BY AGE, SEX, AND AREA OR RESIDENCE
Ridgewood
1-5
6-10
11-15
16-20
21-25
26-30
31-35
36-40
41-45
46-50
5H
Totals
Males
4
12
7
2
0
0
2
3
4
0
0
34
69
Females
3
10
11
1
0
0
3
3
4
0
0
35
Falrlawn*
Males
13
21
5
0
1
0
3
4
7
2
1
57
94
Females
2
8
3
2
0
2
5
9
4
1
1
37
Matawan
Males
9
20
3
0
0
1
1
8
2
1
0
45
83
Females
6
12
7
0
0
2
5
3
1
0
0
38
Elizabeth
Males
7
18
5
0
0
1
1
3
4
2
1
42
Females
6
8
4
0
1
2
3
1
4
2
?
33
75
* Age was not reported for 4 subjects in Fairlawn.
26
-------
TABLE 3. DEMOGRAPHIC CHARACTERISTICS OF ADULTS
Smoking Patterns
Never
ExSmoker
Current Smoker
of Parents {%)
Original
Population
34.0
27.4
38.6
Families
Giving Hair
38.7
35.4
25.9
Parents
Giving Hair
40.4
42.2
17.4
Smoking Patterns of Parents Giving Hair by Area or Residence (?•)
Ridgewood Fairlawn Matawan
Never
ExSmoker
Current Smoker
26.3
68.4
5.3
56.4
30.8
12.8
23.1
57.7
19.2
Elizabeth
44.0
24.0
32.0
Education of Head of Household (%)
Ridgewood
Less than
high school
High school
Greater than
high school
3 fi
7.1
g 3
'
Fairlawn
10>5
18.4
71 ,
Matawan
2.9
5.9
91 2
Elizabeth
15.2
27.3
57.6
27
-------
TABLE 4. HAIR COLOR BY AGE CATEGORY AND SEX
Brown
Blond
Red
Black
Grey i White
Total
Male
88
28
5
3
0
124
Children
Female
56
21
2
1
0
80
Overall
144
49
7
4
0
204
Male
34
4
3
4
9
54
Adults*
Female
52
7
0
1
3
63
Overal 1
86
11
3
5
12
117
* Significant difference in hair color patterns between males and females in
adults but not in children.
28
-------
TABLE 5. HAIR PREPARATION USAGE IN ADULTS BY SEX*
Yes
No
Unknown
Male
3
50
1
Female
28
35
0
Overall
31
85
1
* There were no children reported as using a hair coloring preparation.
29
-------
TABLE 6. FREQUENCY OF HAIRCUT AND HAIR SHAMPOO BY AGE CATEGORY AND SEX
Frequency of Haircut*
Children
Male Female Overall
Adults
Male Female Overall
Every 2 weeks or less
Once a month
Every 3 months
Every 6 months or longer
* Significant differences
Frequency of Hair Shampoo
Every 1-2 days
Once a week
Less than once a week
5
86
27
6
between
Male
35
72
17
0
12
19
49
males and
Children
Female
32
40
8
5
98
46
55
females for
Overal 1
67
112
25
12
38
3
1
both
Male
35
17
2
2
20
27
14
adults and
Adults*
Female
24
36
3
14
58
30
15
children.
Overall
59
53
5
* Significant difference between male and female hair shampoo frequency in adults
but not in children.
30
-------
TABLE 7. LENGTH OF HAIR BY AGE CATEGORY AND SEX*
Short
Med 1 urn
Shoulder
Longer
Total
Male
55
64
3
2
124
Children
Female
9
10
16
45
80
Overall
64
74
19
47
204
Male
38
15
1
0
54
Adults
Female
18
24
12
9
63
Overal 1
56
39
13
9
117
* Significant differences by sex for both adults and children.
31
-------
TABLE 8. LENGTH OF HAIR BY FREQUENCY OF SHAMPOO FOR CHILDREN*
Frequency:
Length: Short
Medium
Shoulder
Longer
Short
Medium
Shoulder
Longer
1-2 days
19
16
0
0
4
3
9
16
Males
Weekly
32
38
2
0
Females
5
3
4
28
Less than once a week
4
10
1
2
0
4
3
1
* Significant interaction for both male and female children, but no differences
found in adult patterns.
32
-------
TABLE 9. TRACE ELEMENT LEVELS IN HUMAN SCALP HAIR*
Arsenic
Barium
Boron
Cadmium
Chromium
Copper
Iron
Lead
Lithium
Manganese
Mercury
Nickel
Selenium
Silver
Tin
Vanadium
Zinc
No. of
Obs.
315
323
322
320
314
321
321
321
321
323
325
318
290
324
316
318
325
Arith.
Mean
0.18
7.39
0.89
0.93
1.21
10.49
39.61
12.31
0.03
1.07
0.73
1.24
0.48
0.35
1.06
0.35
79.87
Total
Geo.
Mean
0.14
2.40
0.40
0.76
0.81
5.71
32.55
8.93
0.02
0.78
0.44
0.86
0.46
0.20
0.79
0.26
58.48
Respondents
Min. Max.
0.02
0.06
0.009
0.17
0.05
0.13
5.52
1.50
0.003
0.07
0.02
0.06
0.16
0.009
0.11
0.03
5.00
0.92
96.00
15.00
4.63
7.50
85.00
174.00
76.10
0.18
6.80
5.60
9.20
1.27
2.70
6.50
1.90
265.00
+_ 1 geo. std. dev.
Lower Upper
0.07
0.56
0.11
0.41
0.33
1.84
17.62
4.19
0.01
0.36
0.15
0.37
0.33
0.06
0.38
0.12
24.85
0.29
10.21
1.41
1.41
2.04
17.74
60.14
19.01
0.05
1.71
1.25
1.98
0.64
0.61
1.68
0.57
137.63
33
-------
TABLE 10. TRACE ELEMENT LEVELS IN HUMAN SCALP
HAIR IN CHILDREN AND ADULTS*
Children
Arsenic
Barium
Boron
Cadmium*
Chromium
Copper
Iron
Lead*
L i th i urn
Manganese
Mercury
Nickel
Selenium
Silver*
Tin* .
Vandium*
Zinc
Adults
Arsenic
Barium
Boron
Cadmium
Chromium
Copper
Iron
Lead
Lithium
Manganese
Mercury
Nickel
Selenium
Silver
Tin
Vanadium
Zinc
No. of
Obs.
200
203
203
202
199
200
202
204
200
203
204
202
184
204
200
202
204
111
116
115
114
111
117
115
113
117
116
117
112
102
116
112
112
117
Percent
Censored
.00
.00
.99
.00
.00
.00
.00
.00
.00
.00
1.96
.00
.00
.00
.00
.00
.00
.00
.00
.00
.00
.00
.85
.00
.00
.00
.00
.85
.00
.00
.00
.00
.00
.00
Arith.
Mean
0.183
6.875
0.768
1.020
1.212
10.503
42.142
13.384
0.029
0.961
0.707
1.229
0.468
0.363
0.932
0.367
74.195
0.176
8.492
1.131
0.751
1.187
10.617
34.964
10.340
0.031
1.269
0.784
1.262
0.505
0.322
1.300
0.314
90.540
Geo.
Mean
0.146
2.065
0.388
0.837
0.861
5.749
34.695
9.726
0.235
0.721
0.461
0.838
0.446
0.235
0.721
0.289
53.314
0.135
3.184
0.416
0.629
0.728
5.682
28.856
7.629
0.024
0.904
0.395
0.892
0.476
0.139
0.948
0.210
69.346
Min.
0.025
0.140
0.009
0.212
0.054
0.501
5.520
1.500
0.003
0.073
0.025
0.120
0.155
0.013
0.110
0.042
5.000
0.018
0.064
0.016
0.169
0.066
0.125
8.470
2.510
0.004
0.150
0.230
0.063
0.155
0.010
0.130
0.027
16.100
Max.
0.923
89.000
1 1 . 000
4.630
6.500
85.000
162.000
76.100
0.129
5.400
4.410
9.200
1.270
2.700
5.900
1.900
265.000
0.880
96.000
15.000
2.860
7.500
82.400
174.000
70.100
0.175
6.800
5.600
7.300
0.975
2.300
6.500
1.600
236.000
GM
0.074
0.479
0.118
0.457
0.372
1.847
18.689
4.517
0.012
0.335
0.171
0.359
0.324
0.091
0.354
0.144
22.040
0.064
0.780
0.102
0.349
0.256
1.809
15.942
3.756
0.012
0.411
0.123
0.387
0.332
0.037
0.428
0.084
31.644
+ GSD*
0.289
8.912
1.273
1.535
1.990
17.895
64.410
20.942
0.047
1.551
1.241
1.957
0.613
0.604
1.467
0.577
128.963
0.285
13.002
1.697
1.135
2.067
17.846
52.231
15.496
0.049
2.033
1.276
2.052
0.681
0.524
2.098
0.526
151.968
* A significant difference (
-------
TABLE 11. A SIGNIFICANCE TABLE FOR HAIR ELEMENT/ELEMENT CORRELATIONS
35
-------
TABLE 12. DUSTFALL TRACE ELEMENT MEANS BY COMMUNITY*
Cadmium
Lead"*"
Zinc
Chromium
Copper
Manganese
Nickel
Ridqewood
0.057 (13)*
5.400 (14)
6.060 (14)
0.131 (8)
3.170 (11)
1.050 (11)
0.390 (11)
Fairlawn
0.078 (12)
8.000 (12)
10.260 (12)
0.221 (8)
5.390 (10)
1.240 (10)
0.380 (10)
Matawan
0.195 (10)
3.860 (12)
8.020 (12)
0.180 (7)
3.900 (10)
1.010 (10)
0.210 (10)
Elizabeth
0.097 (7)
8.430 (7)
9.420 (7)
0.186 (7)
4.800 (7)
1.010 (7)
0.450 (7)
* ( ) indicates number of months for which dustfall samples were available
* Lead is the only element showing significant differences between communities at
«( = 0.05.
Levels reported in mg/m'Vmonth.
36
-------
TABLE 13. HOUSEDUST TRACE ELEMENT ARITHMETIC AND GEOMETRIC MEANS IN RIDGEWOOD*
Arsenic
Barium
Boron
Cadmium
Chromium
Copper
Iron
Lead
Lithium
Manganese
Mercury
Nickel
Selenium
Silver
Tin
Vanadium
Zinc
Arithmetic Means
2.211
1975.571
45.643
18.305
40.714
308.479
12790.714
886.143
5.050
230.071
3.661
33.429
0.080
0.579
25.071
28.286
1483.714
Geometric Means
1.550
329.969
29.548
16.297
39.056
217.022
11956.137
781.332
4.773
204.384
2.042
30.877
0.038
0.359
11.078
22.646
1322.131
* Levels in ug/g dust.
37
-------
::r.r: OF G^II^CANCE OF THE EFFECT OF HAIR-RELATED FACTORS ON CHILDREN'S SCALP HAIR TRACE ELEMENT LEVELS*
CO
00
As
8
Ba
Cd
Cr
Cu
Fe
Li
Hg
Pb
Mn
Ni
Se
Ag
Sn
V
Zn
('.ales
Shampoo Haircut Hair Hair
Frequency Frequency Length Color
0.004
-
0.003 0.02
0.03
0.03
0.02
0.008
-
0.05
-..
0.03
0.03
-
-
-
0.03
-
Females
Shampoo Haircut Hair
Frequency Frequency Length
•. — —
o.oi . o.ooi
0.006
• — —
0.02
_ — —
— _
— _ _
-
0.001
0.02
_
_
-
0.002
0.03
Hair
Color
—
0.007
0.005
_
_
—
_
^
_
-
* Values given are the probability of the observed difference in sample mean levels between factor categories
assuming no difference in the original population. Only values of 0.05 or less are listed.
-------
TABLE 15. TESTS OF SIGNIFICANCE OF THE EFFECT OF HAIR-RELATED FACTORS ON ADULTS' SCALP HAIR TRACE ELEMENT LEVELS*
vo
Males
Shampoo Haircut Hair Hair
Frequency Frequency Length Color
As - 0.04 - 0.04
B ...
Ba - - -
Cd - - - ' 0.03
Cu - O.Oi
Fe - -
Li - - -
Hg ...
Pb - - - -
Hn - -
Hi - - -
Se - - - -
Ag - - 0.004
Sn ...
V - 0.02 0.01
Zn ...
Females
Shampoo Haircut Hair Hair
Frequency Frequency Length Color
-
-
-
-
- _
-
-
...
-
-
-
...
.
_
.
...
* Values given are the probability of the observed difference in sample mean levels between factor categories
assuming no difference in the original population. Only values of 0.05 or less are listed.
-------
TABLE 16. TESTS OF SIGNIFICANCE OF THE EFFECT OF SELECTED FACTORS ON SCALP HAIR TRACE ELEMENT LEVELS,
USING (1) DUSTFALL AS A MEASURE OF ENVIRONMENTAL EXPOSURE AND (2) AREA OF RESIDENCE*
Cd
Cr
Cu
Pb
Nn
N1
Zn
Children
Dustfall Age Sex Education
_
0.002 -
0.02 -
<0.0001
0.02 0.002
<0.0001 - 0.004
0.003
Hair
Length
0.001
0.01
0.05
0.01
-
-
-
(1) Dustfall
Adults
Shampoo
Frequency
0.005
0.02
-
0.007
0.02
0.001
-
Hair
Dustfall Age Sex Education Length Smoking
0.03
-
-
- 0.02
- - - -
0.05
-
* Values given are the probability of the observed difference in sample mean levels between factor categories assuming
no difference in the original population. Only values of 0.05 or less are listed.
(continued)
-------
TABLE 16.(CONTINUED)
As
B
Ba
Cd
Cr
Cu
Fe
L1
Hg
Pb
Mn
N1
Se
Ag
Sn
V
Zn
Area
0.01
-
< 0.0001
0.009
0.01
< 0.0001
< 0.0001
<0.0001
<0.003
-------
TABLE 17. ARITHMETIC MEAN TRACE ELEMENT CONCENTRATIONS IN CHILDREN'S AND
ADULTS' SCALP HAIR BY COMMUNITY FOR SCALP HAIR ELEMENTS WITH
SIGNIFICANT DIFFERENCES BETWEEN COMMUNITIES*
As
Ba
Cd
Cr
Cu
Fe
Li
Hg
Pb
Mn
Ni
Se
Sn
V
Zn
B
Ba
Cd
Cu
Fe
Li
Se
Zn
Ridgewood
0.20
19.20
1.30
1.70
18.10
38.70
0.04
0.58
15.80
1.40
1.70
0.44
1 .20
0.53
76.00
0.60
25.10
0.81
11.90
32.90
0.04
0.46
90.80
Children
Fairlawn
0.22
2.30
1.00
1.00
8.80
29.70
0.04
0.61
10.40
0.80
1.10
0.43
0.80
0.34
68.30
Adults
1.50
4.70
0.89
10.00
25.80
0.04
0.46
86.00
Matawan
0.15
5.90
0.90
1.20
5.00
49.50
0.02
0.73
8.80
0.80
0.90
0.57
0.70
0.28
54.00
0.60
7.10
0.69
6.00
41.60
0.02
0.61
69.90
Elizabeth
0.16
1.20
0.90
1.10
11.60
51.90
0.02
0.91
20.00
0.90
1.30
0.43
1.10
0.33
101.70
1.40
2.70
0.53
15.10
44.30
0.02
0.54
117.40
* Levels are in ug/g of hair.
42
-------
TABLE 18. MEAN TRACE ELEMENT CONCENTRATIONS IN DUSTFALL AND
SCALP HAIR, BY COMMUNITY, FOR SCALP HAIR ELEMENTS
WITH A SIGNIFICANT DUSTFALL EXPOSURE EFFECT
Children'sChildren's
Mean Dustfall Arithmetic Mean Geometric Mean
mg/m2/mo Scalp Hair, ug/g Scalp Hair, yg/g
Chromium
Ridgewood 0.13 1.7 1.3
Fairlawn 0.22 1.0 0.6
Matawan 0.18 1.2 0.9
Elizabeth 0.19 1.1 0.8
Lead
Ridgewood 5.4 15.8 12.1
Fairlawn 8.0 10.4 8.6
Matawan 3.9 8.8 6^5
Elizabeth 8.4 20.0 14.6
Nickel
Ridgewood 0.39 1.6 1.2
Fairlawn 0.38 1.1 0.7
Matawan 0.21 0.9 0.7
Elizabeth 0.45 1.3 1.0
43
-------
TABLE 19. GEOMETRIC MEANS OF >CALP HAIR TRACE ELEMENTS SIGNIFICANTLY
RELA'ED TO AGE, BY AGE AND SFX (_g/c)
Children
B
Ba
Cu
LI
Pb
Mn
Sn
V
Zn
Age
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
Male
Female
2
0.17
0.48
1.7
1.0
4.1
4.8
0.024
0.019
18.6
14.6
0.4
0.9
0.5
1.1
0.16
0.32
41.9
53.90
3
0.14
0.38
0.60
1.80
2.1
3.5
0.015
0.019
7.1
9.0
0.4
0.5
1.1
1.1
0.13
0.24
32.2
28.8
4
0.29
0.7
3.3
0.022
9.6
0.6
0.6
0.26
33.0
5
0.50
0.31
1.2
1.1
3.2
7.2
0.016
0.023
7.5
12.9
0.6
0.6
0.7
1.1
0.26
0.35
32.5
50.9
6
0.29
0.64
1.0
3.5
4.7
2.8
0.022
0.013
8.5
7.7
0.4
1.0
0.6
1.0
0.24
0.42
48.6
34.4
7
0.27
0.41
1.4
5.4
7.2
12.6
0.031
0.029
11.9
12.0
0.6
1.1
0.6
1.4
0.30
0.74
71.7
67.6
8
0.41
0.58
0.8
4.2
4.9
3.4
0.025
0.016
9.7
11.5
0.4
1.2
0.5
1.1
0.21
0.44
41.7
54.0
9
0.23
0.35
1.7
4.8
8.3
5.4
0.024
0.016
14.9
6.9
0.6
1.1
0.6
0.7
0.25
0.35
70.5
55.8
10
0.46
0.42
1.7
5.0
3.8
10.2
0.023
0.027
8.4
9.2
0.6
1.2
0.5
1.0
0.22
0.46
52.4
72.7
11
0.40
0.58
3.9
5.9
5.9
16.6
0.029
0.028
9.3
8.7
0.9
1.1
0.7
0.9
0.24
0.35
43.6
98.3
12
0.55
0.48
1.7
6.2
4.3
6.8
0.024
0-034
8.9
9.6
0.5
0.9
0-4
0.5
0.17
0.30
58.8
71.7
13
0.28
0.61
0.7
9.1
2.4
8.4
0.030
0.023
5.0
6.4
0.3
1.2
0.6
0.9
0.10
0.27
53.4
50.2
14
0.83
0.61
4.4
11.7
21.9
8.9
0.044
0.021
16.9
6.8
1.3
1.7
0-7
0.6
0.40
0.43
146.5
67.2
15
0.33
15.3
22.4
0.044
11.5
1.8
1.5
0.51
95.0
-------
Table 19 (continued)
As
Adults
Ages
Male
Female
Male
Female
16-<:0 21-25
0.23
0.21
0.60
1.76
26-30
0.07
0.16
3.65
1.03
31-35
0.20
0.14
0.19
0.44
36-40
0.15
0.11
C.30
0.75
41-45
0.19
0.09
0.32
0.58
46-50
0.13
0.09
0.07
2.32
51-55
O.OS
0.44
* Levels are in ug/g of hair.
on
-------
TABLE 20. CORRELATIONS OF HOUSEDUST TRACE ELEMENTS TO
SCALP HAIR TRACE ELEMENTS IN RIDGEWOOD (n=19 TO 21)
As
B
Ba
Cd
Cr
Cu
Fe
Li
Hg
Pb
Mn
Ni
Se
Ag
Sn
V
Zn
Concentrations
0.23
0.04
-0.01
-0.31
-0.08
-0.31
0.18
-0-19
0.33*
0.39*
-0.02
0.43*
-0.12
0.02
-0.27
0.48**
-0.15
Logs of Concentrations
0.02
0.01
0.35*
-0.27
0.05
-0.32
0.04
0.24
0.18
0.33*
0.001
0.46*
-0.20
0.02
-0.16
0.28
-0.15
* Significant at a = 0.07
** Significant at a = 0.01
46
-------
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50
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52
-------
TECHNICAL REPORT DATA
(I'k asi reaJ iHtUuctiuns on llie reverse before completing)
I Rt I'ORT NO
_£PA=fiDO/l.-=78-03Zb
•I I I I I I ANl> SUnTITI I!
HUMAN SCALP HAIR: AN ENVIRONMENTAL EXPOSURE INDEX FOR
TRACE ELEMENTS. II. Seventeen Trace Elements in Four
New Jersey.Communities _(19721
/ Aiimomr.)
John P. Creason, Thomas A. Hinners, Joseph E. Bumgarner
anH Ppril Pinkprtnn
3 RECIPIENT'S ACCESSION-NO
5 REPORT DATE
June 1978
6. PERFORMING ORGANIZATION CODE
B PERFORMING ORGANIZATION REPORT NO
10 PROGRAM ELEMENT NO.
ACTVOHANT NO.
9 PERFORMING ORGANIZATION NAME AND ADDRESS
Health Effects Research Laboratory and Environmental
Monitoring and Support Laboratory
Office of Research and Development
THanglP Park, N.P.. ?7711
11.
12 SPONSORING AGENCY NAME AND ADDRESS
Health Effects Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
P Park, N.T.. P7711 -
13. TYPE OF REPORT AND PERIOD COVERED
RTP, NC
14. SPONSORING AGENCY CODE
EPA 600/11
Triangl
TAHY NOT
15 SUPPLEMENTARY
TES
1G ABSTRACT
Seventeen trace elements - arsenic (As), barium (Ba), boron (B), cadmium (Cd),
chromium (Cr), copper (Cu), Iron (Fe), lead (Pb), lithium (Li), manganese (Mn),
mercury (Hg), nickle (Ni), selenium (Se), silver (Ag), tin (Sn), vanadium (V), and
zinc (Zn) - were measured in human scalp hair collected in four eastern New Jersey
communities. Of the seven for which dustfall trace element measurements were
available (lead, nickle, cadmium, copper, zinc, chromium and manganese) lead, nickle
and manganese showed significant positive relationships with children's scalp
hair concentrations. This result supports findings of an earlier New York City
study, even though the dustfall trace element concentrations are much lower in this
study. When all 17 trace elements were tested for geographic differences, all
except boron and silver showed significant differences for children, while 8 of 17
showed significant variation in adults. Several hair-related covariates were
assessed for possible influences on scalp hair trace element levels for both
children and adults. These covariates are evaluated as potential confounding factors
in any future use of hair as an environmental index.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
trace elements
hair
indexes (ratios)
environmental surveys
I) IDENTIFIERS/OPEN ENDED TERMS
New Jersey
c COSATI l;iclil/(iroiip
06, T, F
DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19 SECURITY CLASS (This Report)
21 NO OF PAGES
22.
UNCLASSIFIED
EPA Form 2220-1 (9-73)
53
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