Article
pubs.acs.org/est
Lead Relative Bioavailability in Lip Products and Their Potential
Health Risk to Women
Di Zhao,† Jie Li,† Chao Li,† Albert L. Juhasz,‡ Kirk G. Scheckel,§ Jun Luo,† Hong-Bo Li,*,†
and Lena Q. Ma*,†,∥
†
State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu,
210046, People’s Republic of China
‡
Future Industries Institute, University of South Australia, Mawson Lakes, Adelaide, South Australia 5095, Australia
§
U.S. Environmental Protection Agency, National Risk Management Research Laboratory, Land Remediation and Pollution Control
Division, Cincinnati, Ohio 45224-1701, United States
∥
Soil and Water Science Department, University of Florida, Gainesville, Florida 32611, United States
S Supporting Information
*
ABSTRACT: Recent studies have investigated lead (Pb) concentrations in lip products but little is known about its oral bioavailability.
In this study, 75 lipsticks and 18 lip glosses were assessed for Pb
concentration, while 15 samples were assessed for Pb relative
bioavailability (RBA, relative to Pb acetate absorption) using a mouse
femur assay. Lead concentrations were 0.2−10 185 mg kg−1, with 21
samples exceeding the Chinese limit of 40 mg kg−1. Samples with
orange and pink colors and/or low cost contained higher Pb
concentrations. For samples with Pb > 7500 mg kg−1, Pb was present
due to the addition of lead chromate (PbCrO4) as a colorant, which
was confirmed by X-ray absorption near-edge structure analysis. LeadRBA in 15 samples (87−10 185 mg kg−1) ranged from 23% to 95%,
being significantly higher in moderate Pb (56−95%; 87−300 mg kg−1)
than high Pb samples (23−48%; >300 mg kg−1). The calculation of Pb intake based on Pb-RBA showed that lip product
ingestion contributed 5.4−68% of the aggregate Pb exposure for women depending on Pb concentration. The high Pb
concentration in some lip products together with their moderate Pb-RBA suggests that lip product ingestion is a potential health
concern to women.
■
INTRODUCTION
Lead (Pb) exposure is a common environmental hazard to
humans and is of great concern worldwide. Exposure to Pb
causes loss of appetite, and anemia and sometimes leads to
permanent brain damage or even death.1,2 Pregnant women
and young children are particularly vulnerable to Pb exposure.
It has been demonstrated that women’s blood Pb levels (BLLs)
rise during pregnancy and lactation due to increased bone
turnover, which releases stored skeletal Pb.3 Gulson et al.4
reported a 20% increase in BLLs during pregnancy in women
with BLLs at 3 μg dL−1. In addition to being remobilized during
pregnancy, maternal skeletal Pb may be transported across the
placenta and enter fetal circulation.5 Increased fetal Pb exposure
has been linked with elevated incidences of low birth weight,
miscarriages, and even fetal death.6,7 The risks of maternal Pb
exposure to fetal health warrants study of Pb exposure for
women of childbearing age.
Lead exposure is complicated as it occurs from both dietary
and nondietary pathways.8 Food is the primary ingestion source
of Pb exposure for the general population.9 However, exposure
from nondietary sources such as incidental ingestion of Pb© 2016 American Chemical Society
containing products may constitute a significant source. An
important nondietary Pb exposure pathway for women is
mouthing or ingestion of lip products such as lipsticks and lip
glosses.10,11 Since different pigments have been used to produce
specific colors in paints, it is likely that Pb may be added to lip
products.12 Although a small amount of lip product is applied
each time (∼10 mg), the number of daily applications may vary
depending on the type of lip product and the habit of users.
According to Loretz et al.,13 the average number of applications
among 311 women from the USA who regularly use lipsticks
was 2.4; however, this may vary significantly (up to 20) with
individual circumstances. It has been estimated that a woman
may ingest ∼1.8 kg of lipstick inadvertently over a lifetime,14
which represents a significant Pb exposure pathway depending
on Pb concentration in lip products as well as oral Pb
bioavailability (e.g., Pb fraction absorbed across gastrointestinal
barrier following ingestion).
Received: March 22, 2016
Accepted: May 17, 2016
Published: May 17, 2016
6036
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
were purchased from the Internet and analyzed for Pb
concentrations using ICP-MS following digestion with HNO3
and H2O2. Waxes included beeswax, carnauba wax, cera alba,
cera flava, and osmanthus wax; greases included castor oil,
jojoba oil, coconut oil, palm oil, and olive oil while pigments
having orange, red, pink, purple, and brown colors were
purchased.
Assessment of Pb Relative Bioavailability. To date,
there are no report of Pb relative bioavailability (RBA) in lip
products following oral ingestion. One reason for the lack of
data is the difficulty in replicating noneating exposure from
both a methodological approach and an animal ethics
viewpoint. To circumvent these issues and to provide an
estimate of Pb bioavailability following lipstick ingestion, two
different protocols may be utilized to administer material
during animal bioassays, e.g., single gavage dose (which may
not be representative of lipstick exposure scenarios) and
multiple doses of the matrix via diet to achieve steady state. The
steady state dosing approach provides an advantage of
mimicking daily continuous exposure. Although this approach
has not been utilized previously for the assessment of Pb
bioavailability in lip products, it has been utilized for the
assessment of arsenic- and Pb-RBA in contaminated soils.23−25
As a consequence, the steady state approach (e.g., lipsticks
incorporated into mouse chow) was the most suitable for the
determination of Pb-RBA in lip products.
In this study, an in vivo mouse assay, utilizing Pb
accumulation in femur as the biomarker of Pb exposure was
used to measure Pb-RBA in lip products. Fifteen lip products
with Pb concentrations ranging from 87 to 10 185 mg kg−1
were assessed for Pb-RBA using female Balb/c mice with body
weights of 18−20 g. Following acclimation for 1 week under
standard animal housing conditions (12 h light/dark cycle, 25
°C, and 50% humidity) with free access to Milli-Q water and a
rodent basal diet, mice were fasted overnight, weighed, and
randomly transferred to individual polyethylene cages prior to
exposure.
Lead acetate and lip products were supplied to mice in
amended diets. Initially, mouse basal feed was freeze-dried,
ground to a powder, and then homogenized using a food
processer. Lead acetate solution was thoroughly mixed with
mouse feed to achieve three Pb concentrations (5, 50, and 80
mg Pb kg−1 dw). Lip products (∼1 g) were thoroughly mixed
with mouse feed powder at a ratio of 1:100 by grinding with a
mortar and pestle. Milli-Q water was then added to the mixture
of feed-lip product, which was made into a paste by kneading.
The amended-feed was evenly divided into 21 portions after
which it was pelletized and freeze-dried. A preliminary study
that randomly selected pellets from a given amended-feed
sample showed a relative standard deviation of <5% in Pb
concentration, indicating thorough mixing of Pb acetate or lip
products with the feed.
For Pb exposure, amended-feed (∼5 g dw) was supplied to
individually caged mice at 9:00 am every day. For each lip
product and Pb acetate dose level, 3 separately caged mice were
used as a group. At the end of a 7 d exposure period, remaining
food was removed from cages and weighed with food
consumption calculated as the difference between food supplied
and remaining. During the course of the experiment, mice had
access to Milli-Q water ad libitum. The 7 d exposure period was
selected as it was previously demonstrated that Pb accumulation in animals reaches a near steady state within 7−10 d.26
In recent years, Pb contamination in lip products has gained
increasing attention. In 2007, Campaign for Safe Cosmetics
measured Pb concentrations in 33 brands of lipsticks
manufactured in the USA,15 with Pb being detected in 61%
of products with the highest concentration of 0.7 mg kg−1. On
the basis of microwave-assisted digestion, Hepp et al.16
reported Pb concentrations of 0.1−3.1 mg kg−1 in 20 lipsticks
from the USA. A subsequent extensive survey of 400 lipsticks
from the USA market by Hepp17 reported the highest Pb
concentration of 7.2 mg kg−1, averaging 1.1 mg kg−1. These
reported values are below the US Food and Drug
Administration (FDA) limit of 20 mg Pb kg−1 in cosmetics.18
Similar studies found low Pb concentrations in lip products
from California, USA (n = 32; <0.03−1.3 mg kg−1), and
Harbin, China (n = 30; 0.02−2.0 mg kg−1).10,11 In contrast,
other studies have found high Pb concentrations (1154 and
3760 mg kg−1) in some brands of lip products sold in Iran and
Saudi markets.19,20
While studies have investigated Pb concentrations in lip
products, studies measuring oral Pb bioavailability in lip
products are scarce. When assessing Pb exposure via the
ingestion of lip products, previous studies estimated daily Pb
intake based on total Pb concentration.10,11 While it is a
conservative approach, conceivably, not all Pb in lip products is
absorbed into the bloodstream due to bioavailability constraints.21,22 Therefore, exposure assessment based on total Pb
concentration may overestimate the risk associated with Pb in
lip products. Reliable estimates of Pb exposure and health risks
associated with oral ingestion of lip products depend on the
quantification of Pb bioavailability using in vivo assays.
Therefore, the objective of this study was to (1) examine
total metal concentrations including Pb in 93 lip products, (2)
determine Pb relative bioavailability (RBA, relative to
absorption of Pb acetate) in lip products using a mouse
femur assay, and (3) assess the potential health risks of Pb in lip
products to women based on Pb-RBA. Accurate assessment of
Pb-RBA is an important step to understand the potential health
risks of Pb in lip products to women via oral ingestion.
■
MATERIALS AND METHODS
Sample Collection and Preparation. A total of 93 lip
products, including 75 lipsticks and 18 lip glosses, were
purchased from retail stores or via the Internet in China. Lip
products included popular brands and colors (orange, pink,
brown, red, purple, green, and white), varying in price (0.7−29
USD). Detailed information about lip products is provided in
Table S1. Samples were stored at 4 °C until analyzed. The total
concentrations of 7 metals (Co, Cd, As, Ni, Cr, Zn, and Pb) in
lip products were determined using inductively coupled plasma
mass spectrometry (ICP-MS, NexION300X, PerkinElmer,
USA) following digestion of lip products (0.1 g) with repeated
additions of concentrated HNO3 and H2O2 based on USEPA
Method 3050B. Although the HNO3/H2O2 method could not
completely dissolve lip products due to the high wax and grease
content, preliminary work suggested that Pb concentrations in
lipsticks and lip glosses determined following the HNO3/H2O2
digestion protocol were in good agreement with data derived
using a microwave-assisted HNO3/HF method (Figure S1).
Moreover, the HNO3/H2O2 digestion method has been widely
used for lipstick analysis.10,11,19
To better understand the source of Pb in lip products, typical
raw materials that are commonly used to produce lip products
including wax (n = 5), grease (n = 5), and pigments (n = 22)
6037
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
L−1) were included every 20 samples. The spike and check
recoveries (n = 30) were 101 ± 6.5% and 99 ± 8.3%
respectively.
Lead concentration and Pb-RBA results were expressed as
the mean and standard deviation of 3 replicates. All graphs were
performed using SigmaPlot (version 12.5, Systat Software Inc.,
San Jose, CA, USA). One-way ANOVA was used to determine
the significant differences in concentration of different metals in
lip products, Pb concentration in different raw materials, and
Pb-RBA between different lip products using SAS (version 9.1.3
for Windows).
At the end of the exposure, mice were fasted overnight and
then sacrificed to collect femur samples by dissecting the hind
limbs from the trunk of the body and through the knee joint.
This end point has been used as a biomarker of Pb exposure in
animals.26 Femur samples were immediately steamed to
facilitate the removal of muscle and connective tissue from
the bone. After removal of tissue, the bone was freeze-dried and
then analyzed for Pb concentration using ICP-MS following
digestion using concentrated HNO3 and H2O2 (USEPA
Method 3050B). Following zero correction, a linear dose
response curve (DRC) of Pb concentration in femur was
established for Pb acetate exposed mice (Figure S2). Lead-RBA
in lip products was calculated as the ratio of dose normalized
Pb concentration in femur after lip product exposure to the
slope of the corresponding DRC for Pb acetate (eq 1).
■
RESULTS AND DISCUSSION
Pb Concentrations and Sources in Lip Products. Due
to daily exposure via ingestion, Pb in lip products has been
receiving increasing attention. To determine whether lip
products on the market in China are a source of Pb exposure,
93 lip product samples, varying in color and price, were
purchased from retail stores or via the Internet. These samples
were divided into two types, e.g., lipsticks (n = 75) and lip
glosses (n = 18). Lead was detected in all samples, ranging from
0.2 to 10 185 mg kg−1, averaging 497 mg kg−1 (Figure 1). All lip
Pb relative bioavailability(%)
femur Pb after lip product exposure
=
× 100
Pb dose level via lip product × slope of DRC lead acetate
(1)
Spectroscopic Assessment of Lip Products. To identify
sources of Pb in lip products, two samples (#92 and #93) with
the highest Pb concentration (7781 and 10 185 mg kg−1
respectively) were analyzed by X-ray absorption near-edge
structure (XANES) spectroscopy at the Pb LIII-edge. XAS data
were collected at the Materials Research Collaborative Access
Team beamline 10-ID, Sector 10, at the Advanced Photon
Source of the Argonne National Laboratory, United States.
Detailed spectroscopic analysis is provided in the Supporting
Information.
Human Health Risk Assessment. Assuming an ingestion
rate (IR) of 24 mg d−1 for a young Asian woman with body
weight (BW) of 50 kg,10 daily Pb intake (DItotal and DIbioavailable,
μg Pb kg−1 bw d−1) via lip product ingestion was calculated on
the basis of total Pb concentration (C, mg kg−1) and measured
Pb-RBA (%) for the 15 lip products that were subjected to
bioavailability assays as follows (eqs 2 and 3):
DI total =
C × IR
BW
DIbioavalable =
C × IR × RBA
BW
Figure 1. Lead concentrations in 75 lipstick (+) and 18 lip gloss (▲)
samples from retail stores and the Internet of China. The color of each
point in the figure represents the color in the lip products. The green
dashed and red lines indicate the US Food and Drug Administration
limit of 20 mg kg−1 and Chinese standard of 40 mg kg−1 for cosmetics.
(2)
(3)
products tested in this study exceeded the US FDA acceptable
limit of 0.1 mg Pb kg−1 in candy, which is likely to be consumed
frequently by children.19 Twenty-one out of the 93 samples
(23%) contained Pb concentrations exceeding the FDA and
Chinese limits of 20 and 40 mg Pb kg−1, respectively, in color
additives for cosmetics.18,28 Nine products had Pb concentrations >1000 mg kg−1, with the highest being 10 185 mg kg−1.
Compared to those of other metals in the lip products (Co, Cd,
As, Ni, and Cr), Pb concentrations were significantly higher
(Figure S3), suggesting Pb in lip products is of potential health
concern.
Type, color, and price are important factors influencing Pb
concentration in lip products. With respect to type, 11 out of
75 lipstick samples (15%) contained Pb > 40 mg kg−1
compared to 10 out of 18 (56%) lip gloss samples (Figure
2A). On the basis of color, orange and pink products contained
higher Pb concentrations than brown, red, and purple products
(Figure 2B). Five out of 10 orange products (50%) contained
>1000 mg kg−1 while 13 out of 37 pink products (35%)
contained Pb > 40 mg kg−1. On the other hand, only 1 out of
10 brown (10%) and 2 out of 26 red products (8%) had Pb >
The calculated daily Pb intake values were compared to the
provisional tolerable daily intake (PTDI) of 3.5 μg kg−1 bw d−1
to assess the potential risks of lipstick ingestion by women.27 In
addition, the contribution of lip product ingestion to aggregate
Pb intake (considering Pb intake through dietary, ingestion of
soil and dust, and inhalation of air) was assessed to quantify lip
product ingestion to overall Pb exposure. Calculation of Pb
exposure from dietary, soil, and air pathways is provided in the
Supporting Information.
QA/QC and Data Processing. During digestion of the lip
products using the USEPA 3050B, a cosmetics cream standard
reference material (SRM) GBW09305 from the Chinese
National Standard Reference Center was included. Although
the matrix of the SRM was not lipstick or lip gloss, its similarity
in composition with lip products made it suitable as a SRM for
QA/QC. The accuracy of the HNO3/H2O2 digestion method
was confirmed by an average Pb recovery of 34.2 ± 0.4 mg kg−1
(n = 3) from GBW09305 (37.2 mg kg−1). During measurement
of Pb concentrations in digests of lip products and mouse
femurs using ICP-MS, spiked and check samples (1−10 μg Pb
6038
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
Figure 3. Lead concentrations in raw materials of lip products
including pigments, grease, and wax (A) and variation in Pb
concentration with different pigment colors (B).
Figure 2. Variation in Pb concentration with lip product type (A),
color (B), and price (C). Boxes represent the 25th to 75th percentiles
while solid and dashed lines in boxes denote the median and mean
values, respectively. Error bars represent the 5th and 95th percentiles,
and × signs represent the 1st and 99th percentiles, respectively.
concentrations in some cheap lip products.30,31 In this study,
we found an association of high Pb with high Cr
concentrations. For samples #1−72 with low Pb levels (<40
mg kg−1), Cr concentrations were low (1−10 mg kg−1) with
little variation among lip products (Figure S4A). However, for
samples #73−93 with high Pb concentrations (>40 mg kg−1),
Cr concentration increased with Pb concentration. The molar
ratio of Pb to Cr in low-Pb lip products was <1 (0.04−0.75),
while for high-Pb products, it was ∼1 (0.72−1.10) (Figure
S4B), suggesting the presence of Pb chromate (PbCrO4) as an
additive to achieve orange and pink colors. The XANES
analysis of the two highest Pb orange samples (#92 and #93,
7781 and 10 185 mg Pb kg−1) showed a close agreement in
spectra between Pb in the lip products and PbCrO4 (Figure 4),
confirming our speculation that Pb chromate was added to lip
products.
Pb Relative Bioavailability in Lip Products. Reliable
assessment of Pb exposure to women depends not only on total
Pb concentration but also on Pb bioavailability in lip products.
To date, reports of Pb-RBA in lip products are lacking,
although one study showed an increase in blood Pb
concentration following oral daily gavage of a lipstick sample
(19 mg kg−1 Pb) to rats for 12 weeks.20 To accurately quantify
Pb exposure following ingestion of lip products, a mouse
bioassay was conducted to determine Pb-RBA in 15 lip
products (8 lip glosses and 7 lipsticks) with Pb concentrations
ranging from 87 to 10 185 mg kg−1. Low Pb lip products (<40
mg kg−1) were not selected as it was difficult to accurately
quantify Pb accumulation in mice at these concentrations.
Mouse femur was used as the biomarker of Pb exposure, since
Pb preferentially accumulates in bone compared to other
organs/tissue during long-term exposure.32 Preliminary studies
demonstrated that Pb accumulation in mouse femur following
Pb acetate exposure was linearly dose dependent (Figure S2),
confirming the suitability of using Pb-femur accumulation
following 7 d exposure to measure Pb-RBA in lip products.
In this study, lip products with Pb concentrations of <40 mg
kg−1 Pb (Chinese limits) were considered as having low Pb
levels, whereas 40−300 mg kg−1 Pb was moderate and >300 mg
kg−1 was high. On the basis of femur as the biomarker of Pb
exposure, Pb-RBA varied greatly from 23 ± 2.5 (#82) to 95 ±
9.8% (#73), averaging 45% (Figure 5). Lead-RBA (56−95%)
was significantly higher for products #73−77 having moderate
Pb concentration (87−299 mg kg−1) compared to 23−48% for
products #78−93 having high Pb concentrations (325−10 185
mg kg−1). For the two lip products (#73 and #75) with the
lowest Pb concentrations (87 and 124 mg kg−1) among the 15
samples, Pb-RBA was the highest (95 ± 9.8% and 70 ± 6.9%),
40 mg kg−1, while Pb concentrations in 6 purple products were
below the FDA limit of 20 mg kg−1 (Figure 2B). In addition to
lip product type and color, Pb concentration in lip products
tended to decrease with increasing price (Figure 2C). All lip
products with Pb >40 mg kg−1 were <5 USD, while Pb
concentrations in samples costing >5 USD were below 20 mg
Pb kg−1.
Previous studies have assessed Pb concentrations in lip
products from Europe and US, showing significantly lower Pb
concentrations than this study. Piccinini et al.29 reported Pb
concentrations of <0.1−3.8 mg kg−1 for 223 lip products from
15 European countries, but showing higher Pb concentration in
lipsticks (average 0.8 mg kg−1) than in lip glosses (0.4 mg
kg−1). Similarly, more expensive lipsticks had lower Pb
concentrations. Hepp17 reported the average Pb concentration
in 400 lipsticks on the USA market was 1.1 mg kg−1. However,
high Pb concentrations (2028−3760 mg kg−1) were observed
in 3 brands of lipstick sold in Saudi markets.19 Similarly, a high
Pb concentration (1154 mg kg−1) was observed for one lipstick
in Iran.20 However, lip products from the USA, Italy, and
France did not show Pb concentrations above the FDA limit of
20 mg kg−1,19 suggesting Pb contamination in lip products
should attract more attention in developing countries where
safety control is poorly enforced during manufacturing.
It is known that metal contamination in lip products may
originate from natural or synthetic metal-containing ingredients.14 Gao et al.11 showed that lip products are often made
of the following materials: 20−30% wax, 50−70% grease, and
5−15% pigment. Thus, typical wax, grease, and pigments with
different colors that are commonly used to produce lip
products were purchased and analyzed for Pb concentration.
Analyses showed that the raw materials contained low
concentrations of Pb, although pigments (average 1.0 mg
kg−1, n = 22) contained significantly higher Pb concentration
than grease (average 0.01 mg kg−1, n = 5) or wax (0.04 mg
kg−1, n = 5) (Figure 3A). In addition, little difference in Pb
concentration was found in pigments with different colors
(Figure 3B). Hence, it can be concluded that high levels of Pb
in the lip products were probably not caused by Pb from raw
materials such as pigments, greases, and waxes.
Some Pb minerals, including Pb tetroxide (red), Pb
monoxide (yellow), Pb chromate (yellow), Pb bromide
(white), Pb iodide (yellow), Pb carbonate (white), and Pb
sulfate (black), which are frequently used as colorants, might be
added by manufacturers, thereby leading to high Pb
6039
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
Figure 4. Normalized XANES spectra (a) and corresponding derivatives (b) for two lip product samples #92 and #93 with Pb concentration of 7781
and 10 185 mg kg−1 and Pb chromate (PbCrO4).
while significantly lower Pb-RBA values (34 ± 0.1% and 31 ±
7.1%) were observed for products #92 and #93 with the highest
Pb concentrations (7781 and 10 185 mg kg−1). Excluding the
significantly higher Pb-RBA for moderate-Pb lip products
(#73−77), Pb-RBA showed little variation with Pb concentration and there was no significant difference (p > 0.05)
between lip gloss and lipstick, averaging ∼40% (Figure 5).
The significantly higher Pb-RBA values for moderate-Pb lip
products compared to high-Pb products may be due to the
addition of different Pb minerals to moderate-Pb lip products,
which are more bioavailable than PbCrO4. Although XANES
analysis was not undertaken for lip products #73 and #75, their
molar ratios of Pb to Cr (0.72−0.76) were <1 (Figure S4B),
suggesting that Pb in the moderate-Pb samples was not present
as PbCrO4. Other Pb minerals, such as oxides or carbonate,
with higher Pb solubility in gastrointestinal fluid compared to
PbCrO4 (67−73% vs. 9%) were presumably used in these two
products,33 thereby leading to higher Pb-RBA. For future
studies, analysis of Pb speciation in moderate-Pb samples
Figure 5. Lead relative bioavailability in 15 lip products (8 lip gloss
and 7 lipstick samples) determined using mouse femur as a biomarker
after 7 d of lip product exposure via diet. For samples #73−93, total Pb
concentration increased from 87 to 10 185 mg kg−1. Bars represent the
mean and standard deviation of three replicates.
Table 1. Estimated Daily Pb Intake Values for Women with Body Weight of 50 kg and Lip Product Ingestion Rate of 24 mg d−1
Based on Total Pb and Bioavailable Pb in 15 Lip Products
estimated daily Pb intake
(μg kg−1 bw d−1) based on
contribution of lip product ingestion to
aggregate Pb exposure (%) based on
sample
total Pb (mg kg−1)
bioavailable Pb (mg kg−1)a
total Pbb
bioavailable Pbc
total Pbd
bioavailable Pbe
#73
#75
#76
#77
#78
#79
#80
#81
#82
#83
#86
#88
#91
#92
#93
87
124
245
299
325
354
401
473
515
698
1800
3409
7106
7781
10185
83
87
138
192
140
169
153
208
119
173
597
1033
3414
2631
3056
0.04
0.06
0.12
0.14
0.16
0.17
0.19
0.23
0.25
0.34
0.86
1.64
3.41
3.74f
4.89f
0.04
0.04
0.07
0.09
0.07
0.08
0.07
0.10
0.06
0.08
0.29
0.50
1.64
1.26
1.47
1.04
1.55
3.05
3.54
4.02
4.26
4.74
5.68
6.14
8.17
18.4
30.0
47.2
49.5
56.1
5.41
5.41
9.09
11.4
9.09
10.3
9.09
12.5
7.89
10.3
29.3
41.7
70.1
64.3
67.7
a
Bioavailable Pb was the product of total Pb concentration and Pb relative bioavailability. bBased on total Pb concentration in the lip products.
Based on bioavailable Pb concentration in the lip products. dBased on total Pb in both lip product and other exposure pathways, which is described
in Table S3. eBased on bioavailable Pb in both lip product and other exposure pathways, which is described in Table S3. fBold values indicate the
estimated daily Pb intake exceeding the PTDI of 3.5 μg kg−1 bw d−1.
c
6040
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
aggregate Pb exposure, while ingestion of samples with Pb <
500 mg kg−1 contributed <10%.
In addition, the health risk of Pb exposure to lip products for
women of childbearing age is of particular concern, as
researchers have shown that Pb previously accumulated in
the mother’s bones from past Pb exposure may be released into
the bloodstream during pregnancy.3,4 Released Pb may pass
through the placenta or be present in mother’s milk, thereby
impacting the fetus or infant’s developments.3 It was recently
reported that the Pb maternal to fetal transfer ratio may be as
high as 0.85.40 Therefore, excessive Pb intake via lip products
for pregnant women or women prior to conception may subject
the fetus and infant to elevated Pb exposure. Assuming that a
female uses lip products containing an average Pb concentration of 497 mg kg−1 (the average value of samples tested in
this study) and Pb-RBA of 40% from the age of 12 (with an
average daily ingestion of 24 mg) and is pregnant at the age of
25, a total of 22.6 mg of Pb will be absorbed from lip products
prior to pregnancy. The accumulated Pb via lip product
ingestion represents a source for remobilization, which has the
potential to impact the fetus or infant’s developments.3
Moreover, using XANES analysis, PbCrO4 was identified as
the dominant Pb specie in lip products with high Pb
concentrations. Hexavalent Cr (CrVI) is a well-recognized
carcinogen. Presumably, when PbCrO4 in lip products was
solubilized in the gastrointestinal tract, CrVI may be available for
absorption into the systemic circulation, posing an additional
health risk. In this study, although Cr bioavailability was not
determined, total Cr concentration in the 93 lip products
ranged from 0.5 to 2736 mg kg−1 (Figure S4A). On the basis of
total concentration, daily Cr intake via lip products ranged from
0.01 to 65.7 μg d−1 for a woman with a lip product ingestion
rate of 24 mg d−1. Ingestion of lip products containing Cr
>1000 mg kg−1 would cause daily Cr intake exceeding the
recommended daily Cr intake of 25 μg d−1 for women.41 Since
Cr bioavailability in lip products was not performed, calculated
daily intake values may represent a worst-case scenario.
However, Cr intake and bioavailability assessment from the
use of lip products may warrant further investigation.
should be undertaken to explain the variability in Pb-RBA
among lip products.
Implications for Refining Risk Assessment for Women
Using Lip Products. When assessing Pb exposure via the
ingestion of lip products, previous studies rarely considered Pb
bioavailability.10,11 In this study, we found that extremely high
Pb concentrations in some lip products (e.g., 10 185 mg kg−1)
were due to the addition of PbCrO4 as a colorant (Figure 4).
The high Pb concentrations together with moderate Pb-RBA
(∼40%, Figure 5) make lip products an important Pb exposure
source for women using these products for adornment
purposes.
To quantify the contribution of Pb intake via lip products to
aggregate Pb exposure, we calculated daily Pb intake for women
through oral ingestion of lip products based on total and
bioavailable Pb values. Only the 15 lip products that measured
for Pb-RBA were included in the analysis. On the basis of total
Pb concentration, daily Pb intake via the 15 lip products ranged
from 0.04 to 4.9 μg kg−1 bw d−1 for a woman with body weight
of 50 kg and lip product ingestion rate of 24 mg d−1 (Table 1).
Oral ingestion of the three lip products with Pb concentrations
>7000 mg kg−1 led to daily Pb intake close to or exceeding the
provisional tolerable daily Pb intake (PTDI) value of 3.5 μg
kg−1 bw d−1.27 However, with the inclusion of Pb-RBA, daily Pb
intake values were significantly reduced to 0.04−1.5 μg kg−1 bw
d−1, with all values below the PTDI value. However, for a high
rate of lip product ingestion (above the 95th percentile; 87 mg
d−1),10 ingestion of some lip products (e.g., #93) may lead to
Pb intake (5.31 μg kg−1 bw d−1) exceeding the PTDI value
even when Pb-RBA was incorporated into calculations. This Pb
exposure scenario may potentially occur considering that some
women may be required to wear lipstick or lip gloss as a
condition of employment resulting in a higher number of
applications per day compared to the general public.
Ingestion of lip products is not the only Pb exposure pathway
for women. Lead may enter human body through inhalation of
air particulates, oral ingestion of soil and dust, and consumption
of water and food (e.g., rice, vegetables, and meat). Therefore,
it is necessary to assess the relative contribution of lip product
ingestion to aggregate Pb exposure. Tables S2 and S3 show the
calculation of Pb intake through these pathways, with the
assumption that Pb concentrations in these media were
equivalent to Pb guideline values based on Chinese environmental and food standards.34−37 Ingestion or inhalation rates
for these media were adopted from Li et al.38 and Chen et al.,39
while Pb bioavailability was set as 50%, 10%, 10%, and 50% for
inhalation, food consumption, drinking water, and soil
ingestion.39
On the basis of total Pb in lip products and other media, oral
ingestion of lip product #73 (87 mg Pb kg−1) contributed little
(1.0%) to overall Pb exposure, whereas 56% of aggregate Pb
exposure came from sample #93 (10 185 mg Pb kg−1) when
ingested (Table 1). When taking Pb bioavailability into
consideration for Pb exposure via lip product and other
pathways, Pb contribution from lip products increased
compared to calculations based solely on total Pb concentration
due to higher Pb biavailability in lip products than the default
values for other Pb sources. Approximately 5% of aggregate Pb
intake resulted from the ingestion of lip product #73, while the
contribution of lip product Pb to overall Pb exposure reached
68% when lip product #93 (10 185 mg kg−1) was used. In
general, oral ingestion of lip products with Pb concentrations
>1800 mg kg−1 may lead to a contribution of >30% to
■
ASSOCIATED CONTENT
S Supporting Information
*
The Supporting Information is available free of charge on the
ACS Publications website at DOI: 10.1021/acs.est.6b01425.
Descriptions of types, colors, and prices of the 93 lip
products and estimated daily Pb intake through all
exposure routes for adults (Tables S1−S3); comparison
of Pb concentrations determined using HNO3/H2O2 and
the microwave-assisted HNO3/ HF methods, linear dose
response of Pb accumulation in mouse femur following
Pb acetate exposure, concentration of other metals in the
lip products, and molar ratio of Pb to Cr in lip products
(Figures S1−S4). (PDF)
■
AUTHOR INFORMATION
Corresponding Authors
*Tel./Fax: +86 025 8968 0637; e-mail: lqma@ufl.edu.
*Tel./Fax: +86 025 8968 0637; e-mail: [email protected].
Notes
The authors declare no competing financial interest.
6041
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
■
(18) FDA. Lipstick and Lead: Questions and Answers. U.S. Food and
Drug Administration (FDA): Washington, DC, 2011; http://www.fda.
gov/cosmetics/productsingredients/products/ucm137224.htm.
(19) Al-Saleh, I.; Al-Enazi, S.; Shinwari, N. Assessment of lead in
cosmetic products. Regul. Toxicol. Pharmacol. 2009, 54 (2), 105−113.
(20) Hashemi-Moghaddam, H.; Shiravi, A.; Shamsabad, F. S.; Torabi,
M.; Taviraei, M. R. Disposition of lead (Pb) in brain of rats following
oral exposure to lipstick. J. Paramedical Sci. 2015, 6, 79−84.
(21) Ruby, M. V.; Davis, A.; Schoof, R.; Eberle, S.; Sellstone, C. M.
Estimation of lead and arsenic bioavailability using a physiologically
based extraction test. Environ. Sci. Technol. 1996, 30 (2), 422−430.
(22) Ruby, M. V.; Schoof, R.; Brattin, W.; Goldade, M.; Post, G.;
Harnois, M.; Mosby, D. E.; Casteel, S. W.; Berti, W.; Carpenter, M.;
Edwards, D.; Cragin, D.; Chappell, W. Advances in evaluating the oral
bioavailability of inorganics in soil for use in human health risk
assessment. Environ. Sci. Technol. 1999, 33 (21), 3697−3705.
(23) Li, J.; Li, C.; Sun, H. J.; Juhasz, A. L.; Luo, J.; Li, H. B.; Ma, L. Q.
Arsenic Relative Bioavailability in Contaminated Soils: Comparison of
Animal Models, Dosing Schemes, and Biological End Points. Environ.
Sci. Technol. 2016, 50 (1), 453−461.
(24) Bradham, K. D.; Scheckel, K. G.; Nelson, C. M.; Seales, P. E.;
Lee, G. E.; Hughes, M. F.; Miller, B. W.; Yeow, A.; Gilmore, T.; Serda,
S. M.; Harper, S.; Thomas, D. J. Relative bioavailability and
bioaccessibility and speciation of arsenic in contaminated soils.
Environ. Health Perspect. 2011, 119 (11), 1629−1634.
(25) Juhasz, A. L.; Weber, J.; Naidu, R.; Gancarz, D.; Rofe, A.; Todor,
D.; Smith, E. Determination of cadmium relative bioavailability in
contaminated soils and its prediction using in vitro methodologies.
Environ. Sci. Technol. 2010, 44 (13), 5240−5247.
(26) Casteel, S. W.; Weis, C. P.; Henningsen, G. M.; Brattin, W. J.
Estimation of relative bioavailability of lead in soil and soil-like
materials using young swine. Environ. Health Perspect. 2006, 114 (8),
1162−1171.
(27) FAO/WHO. Safety evaluation of certain food additives and
contaminants. Food Additives Series: 59. Prepared by the 68th
meeting of the Joint FAO/WHO Expert Committee on Food
Additives (JECFA); World Health Organization (WHO): Geneva,
2000; http://www.inchem.org/documents/jecfa/jeceval/jec_1260.
htm.
(28) Chinese Ministry of Health. Hygienic Standard for Cosmetics;
Chinese Ministry of Health: Beijing, 2007.
(29) Piccinini, P.; Piecha, M.; Torrent, S. F. European survey on the
content of lead in lip products. J. Pharm. Biomed. Anal. 2013, 76, 225−
233.
(30) Beauchemin, S.; MacLean, L. C.; Rasmussen, P. E. Lead
speciation in indoor dust: a case study to assess old paint contribution
in a Canadian urban house. Environ. Geochem. Health 2011, 33 (4),
343−352.
(31) Turner, A.; Kearl, E. R.; Solman, K. R. Lead and other toxic
metals in playground paints from South West England. Sci. Total
Environ. 2016, 544, 460−466.
(32) Marschner, B.; Welge, P.; Hack, A.; Wittsiepe, J.; Wilhelm, M.
Comparison of soil Pb in vitro bioaccessibility and in vivo
bioavailability with Pb pools from a sequential soil extraction. Environ.
Sci. Technol. 2006, 40 (8), 2812−2818.
(33) Rasmussen, P. E.; Beauchemin, S.; Chenier, M.; Levesque, C.;
MacLean, L. C.; Marro, L.; Jones-Otazo, H.; Petrovic, S.; McDonald,
L. T.; Gardner, H. D. Canadian house dust study: Lead bioaccessibility
and speciation. Environ. Sci. Technol. 2011, 45 (11), 4959−4965.
(34) Chinese Ministry of Health, Chinese Food Standards. Maximum
Levels of Contaminants in Food; GB2762−2012, Standard Press of
China: Beijing, 2012.
(35) State Environmental Protection Administration of the People’s
Republic of China. Ambient Air Quality Standards; GB 3095−2012,
China Environmental Sciences Press: Beijing, 2012.
(36) Chinese Ministry of Health. Standards for Drinking Water
Quality; GB5749−2006, Standard Press of China: Beijing, 2006.
ACKNOWLEDGMENTS
This work was supported in part by Jiangsu Provincial
Innovation Team Program and Jiangsu Provincial Double−
Innovation Program.
■
REFERENCES
(1) Koller, K.; Brown, T.; Spurgeon, A.; Levy, L. Recent
developments in low-level lead exposure and intellectual impairment
in children. Environ. Health Perspect. 2004, 112 (9), 987−994.
(2) Plumlee, G. S.; Durant, J. T.; Morman, S. A.; Neri, A.; Wolf, R. E.;
Dooyema, C. A.; Hageman, P. L.; Lowers, H. A.; Fernette, G. L.;
Meeker, G. P.; Benzel, W. M.; Driscoll, R. L.; Berry, C. J.; Crock, J. G.;
Goldstein, H. L.; Adams, M.; Bartrem, C. L.; Tirima, S.; Behbod, B.;
von Lindern, I.; Brown, M. J. Linking geological and health sciences to
assess childhood lead poisoning from artisanal gold mining in Nigeria.
Environ. Health Perspect. 2013, 121 (6), 744−750.
(3) Silbergeld, E. K. Lead in bone: Implications for toxicology during
pregancy and lactation. Environ. Health Perspect. 1991, 91, 63−70.
(4) Gulson, B. L.; Jameson, C. W.; Mahaffey, K. R.; Mizon, K. J.;
Korsch, M. J.; Vimpani, G. Pregnancy increases mobilization of lead
from maternal skeleton. J. Lab. Clin. Med. 1997, 130, 51−62.
(5) Gulson, B. L.; Mizon, K. J.; Korsch, M. J.; Palmer, J. M.;
Donnelly, J. B. Mobilization of lead from human bone tissue during
pregnancy and lactation−a summary of long-term research. Sci. Total
Environ. 2003, 303 (1−2), 79−104.
(6) Zhu, M.; Fitzgerald, E. F.; Gelberg, K. H.; Lin, S.; Druschel, C. M.
Maternal low-level lead exposure and fetal growth. Environ. Health
Perspect. 2010, 118 (10), 1471−1475.
(7) Edwards, M. Fetal death and reduced birth rates associated with
exposure to lead-contaminated drinking water. Environ. Sci. Technol.
2014, 48 (1), 739−746.
(8) Levin, R.; Brown, M. J.; Kashtock, M. E.; Jacobs, D. E.; Whelan,
E. A.; Rodman, J.; Schock, M. R.; Padilla, A.; Sinks, T. Lead Exposures
in U.S. children, 2008: Implications for prevention. Environ. Health
Perspect. 2008, 116 (10), 1285−1293.
(9) Dong, Z.; Hu, J. Development of lead source-specific exposure
standards based on aggregate exposure assessment: Bayesian inversion
from biomonitoring information to multipathway exposure. Environ.
Sci. Technol. 2012, 46 (2), 1144−1152.
(10) Liu, S.; Hammond, S. K.; Rojas-Cheatham, A. Concentrations
and potential health risks of metals in lip products. Environ. Health
Perspect. 2013, 121 (6), 705−710.
(11) Gao, P.; Liu, S.; Zhang, Z.; Meng, P.; Lin, N.; Lu, B.; Cui, F.;
Feng, Y.; Xing, B. Health impact of bioaccessible metal in lip cosmetics
to female college students and career women, northeast of China.
Environ. Pollut. 2015, 197, 214−220.
(12) Brown, V. J. Metals in lip products: A cause for concern?
Environ. Health Perspect. 2013, 121 (6), A196.
(13) Loretz, L. J.; Api, A. M.; Barraj, L. M.; Burdick, J.; Dressler, W.
E.; Gettings, S. D.; Han Hsu, H.; Pan, Y. H.; Re, T. A.; Renskers, K. J.;
Rothenstein, A.; Scrafford, C. G.; Sewall, C. Exposure data for
cosmetic products: lipstick, body lotion, and face cream. Food Chem.
Toxicol. 2005, 43 (2), 279−291.
(14) Soares, A. R.; Nascentes, C. C. Development of a simple
method for the determination of lead in lipstick using alkaline
solubilization and graphite furnace atomic absorption spectrometry.
Talanta 2013, 105, 272−277.
(15) Campaign for Safe Cosmetics. A poison kiss: The problem of
lead in lipstick. Safe Cosmetics Action Network, 2007; http://www.
safecosmetics.org/article.php?id=327 (Accessed May 23, 2012).
(16) Hepp, N. M.; Mindak, W. R.; Cheng, J. Determination of total
lead in lipstick: Development and validation of a microwave-assisted
digestion, inductively coupled plasma-mass spectrometric method. J.
Cosmet. Sci. 2009, 60 (4), 405−414.
(17) Hepp, N. M. Determination of total lead in 400 lipsticks on the
U.S. market using a validated microwave-assisted digestion, inductively
coupled plasma-mass spectrometric method. J. Cosmet. Sci. 2012, 63,
159−176.
6042
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043
Article
Environmental Science & Technology
(37) State Environmental Protection Administration of the People’s
Republic of China. Environmental Quality Standard for Soils;
GB15618−1995, Standard Press of China: Beijing, 1995.
(38) Li, G.; Sun, G. X.; Williams, P. N.; Nunes, L.; Zhu, Y. G.
Inorganic arsenic in Chinese food and its cancer risk. Environ. Int.
2011, 37 (7), 1219−1225.
(39) Chen, L.; Xu, Z.; Liu, M.; Huang, Y.; Fan, R.; Su, Y.; Hu, G.;
Peng, X.; Peng, X. Lead exposure assessment from study near a leadacid battery factory in China. Sci. Total Environ. 2012, 429, 191−198.
(40) Monnot, A. D.; Christian, W. V.; Abramson, M. M.; Follansbee,
M. H. An exposure and health risk assessment of lead (Pb) in lipstick.
Food Chem. Toxicol. 2015, 80, 253−260.
(41) Dietary Reference Intakes: Vitamin A, Vitamin K, Arsenic, Boron,
Chromium, Copper, Iodine, Iron, Manganese, Molybdenum, Nickel, Silicon,
Vanadium and Zinc; National Academy Press: Washington, DC, 2001;
pp 620.
6043
DOI: 10.1021/acs.est.6b01425
Environ. Sci. Technol. 2016, 50, 6036−6043