A Pilot Survey of Mercury in Drugs, Cosmetics and Household Products Using Reliable Analytical Methods

doi:10.4236/jcdsa.2013.34039

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Journal of Cosmetics, Dermatological Sciences and Applications, 2013, 3, 256-262

Published Online December 2013 (http://www.scirp.org/journal/jcdsa)

http://dx.doi.org/10.4236/jcdsa.2013.34039

Open Access JCDSA

A Pilot Survey of Mercury in Drugs, Cosmetics and

Household Products Using Reliable Analytical Methods

Lian Liang1*, John Gilkeson2, Ed Swain3, Elizabeth Bennett1, Maya Li1, Mei Deng1, Patrick Pang1

1Cebam Analytical, Inc., Bothell, USA; 2Minnesota Pollution Control Agency, Resource Management and Assistance Division, St.

Paul, USA; 3Minnesota Pollution Control Agency, Environmental Assessment and Outcomes Division, St. Paul, USA.

Email: *[email protected]

Received October 8th, 2013; revised November 2nd, 2013; accepted November 10th, 2013

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

ABSTRACT

The concentration of mercury (Hg) was accurately determined in more than 228 drugs, cosmetics and household prod-

ucts manufactured in a variety of countries. Some drugs were found to contain up to 4424 ppb Hg, and some skin

creams contained up to 2769 ppm Hg. Hg in skin creams was found to be almost 100% elemental Hg (Hg0), a volatile

species of Hg. Hg0 can enter the human body through inh alation and skin absorp tion, potentially resultin g in the serious

consequence of mercury poisoning. The mercury can also volatilize, contaminating the surrounding air. Other people,

for example, infants and children, who are close to or contacting the skin of the person using the cosmetics, can also

absorb the mercury. Total mercury (THg) was determined by combustion/trap/CVAFS. Methyl mercury (MeHg) and

inorganic mercury (Hg2+) were determined by the ethylation based method. The emission of Hg0 was determined by

evaporation/trap/CVAFS. All analyses were performed in accordance with explicit quality assurance and quality control

protocols and procedures.

Keywords: Mercury Speciation; Drugs; Cosmetics; Households; Reliable Methods

1. Introduction

As a well-recognized toxic metal [1], Hg has drawn at-

tention from scientists all over the wo rld to investigate its

effects on the environment and human health. However,

the research works focused on its biogeochemical cycling

in which water, soil, air, biota were directly involved [2,

3]. Compared to cycling in environmental media, little

attention has been paid to drugs and cosmetics. Because

drugs are directly taken into human gastrointestinal sys-

tem, and cosmetics are directly put on human skin, these

products can affect human health more directly and im-

mediately than Hg in media from the surrounding envi-

ronment [4]. To protect human health and environment,

accurately monitoring Hg in these products is necessary,

and this research indicates that there is much work to be

done.

Hg has a long history of use in many cultures as a

readily available chemical that seems to have net bene-

fits as a preservative or active ingr edient in personal care

products, and pharmaceuticals. However, these uses are

now seen to be unnecessary, counterproductive, or better

accomplished by substituting modern chemical agents

that have fewer negative effects, are biodegradable, and

do not have significantly greater cost [5]. Due to the per-

sistence and toxicity of Hg and its compounds, govern-

ment agencies should consider banning its use in human

personal care and pharmaceutical products. Government

agencies have repeatedly warned the public about the

dangers [6-10]. However, the situation apparently has not

been improved in recent years.

Some drug and biologic products are still being manu-

factured with Hg as a preservative, fungicide, or antisep-

tic, even though effective biodegradable non-Hg alterna-

tives are available. Some high level Hg-containing anti-

aging and skin lightening creams, lotions, and soaps are

being produced by manufacturers from developing coun-

tries, and the availability of these products seems to be

increasing in recent years [4]. These products rarely

identify Hg as an ingredient and are distributed world-

wide through various channels of commerce, marketed

primarily to women. Since these products “work well”,

*Corresponding autho

A Pilot Survey of Mercury in Drugs, Cosmetics and Household Products Using Reliable Analytical Methods 257

some women favor th e products and it is difficult to per-

suade people not to use them. Most people who use these

products don’t know that they contain high levels of Hg,

and that the Hg in these products can cause damage to

the kidneys and nervous system and even interfere with

the development of the brain in the unborn and in young

children. Children can be exposed just by touching a

parent or even a countertop contaminated with residual

product. Some women even know how dangerous the

products could be, and they still use them after weighing

the “benefits” of “beauty” against the dangers.

Since most of these products are oil containing sub-

stances, analysis of these products for Hg and its com-

pounds using traditional wet chemistry methods has b een

difficult as both analytes and media are volatile. This

might account for the fact that governments issued

warnings about some dangerous products but did not

identify the mercury concentrations found in them. Even

the manufacturers may not know exactly how much Hg

is in their products. This can make it difficult for gov-

ernments to establish necessary regulations for limiting

and banning the use of Hg in these products. Any amount

of mercury that is intentionally added is too much mer-

cury. US FDA has established a limit of 1 ppm as the

threshold for an “adulterated product.”

A total mercury (THg) analytical method based on

combustion/trap/CVAFS has been developed and pub-

lished [11-13]. Using the method, samples including liq-

uids, solids and gases were introduced into the system

without the need for sample preparation. In the system,

mercury compounds were decomposed at 800˚C into

elemental Hg (Hg0) which was then carried to a gold trap

and collected onto the trap by amalgamation. Hg0 col-

lected on the trap was finally measured by CVAFS. In

the past years, the method detection limit has been fre-

quently determined and found to be around 0.1 ng/g for

liquids and solids. The method has been successfully ap-

plied for determination of Hg in crude oils and related

products, and the performance such as the accuracy and

validity of the technique has been detailed in our previ-

ous publications [14-17]. In this pilot survey, this tech-

nique was used for determination of THg in the products,

and ensured high quality results for the study.

2. Experimental

Except where specifically addressed below, equipment,

materials, and methods used for this work are the same as

those described in our previous publications. A BR(III)

Hg analyzer (Brooks Rand, Seattle) was used for meas-

urement of elemental Hg (Hg0). A sensitive balance

(Mettler, AT261, d = 0.01 mg) was used for weighing

sample aliquots.

2.1. Determination of THg by

Combustion/Trap/CVAFS Method

2.1.1. The Setup of the System

The combustion/trap/CVAFS system has been described

in our previous publications [13]. To suit various prod-

ucts, a combustion column with an 8 mm inside diameter

was used which is larger than that (6 mm) used in our

previous system. The working conditions are the same,

i.e., 800˚C for combustion, 20˚C to 800˚C for sample

introduction, and the flow rate of carry air is 250 to 300

mL/min.

2.1.2. Sa mpl e Introducti on

Samples, liquid or liquid-like, were drawn and injected

into the combustion column using syringes (Hamilton,

Nevada, USA), while solid or solid-like samples were

weighed into quartz glass boats using the sensitive bal-

ance, then the boats were inserted into the column for

analysis (Figure 1).

2.1.3. Calib ra t i on of Resul ts and Quality Cont rol

Standards, 10 ng/mL to 1000 ng/mL of methyl Hg

(MeHg) as Hg prepared in toluene, were used for calibra-

tion depending on Hg concentration levels of samples. A

100 ppm Hg standard (Canostand™, USA) was diluted

with toluene and used as the lab control sample (LCS)

for liquid samples, while certified reference materials

such as NIST1575a (Pine leaves), IAEA 142 (fish tissue),

Dorm-2 (fish tissue), and NIST 2709 (soil) were used for

solid samples. All samples were analyzed in duplicate,

and related percent differences (RPD) between duplicate

analyses were <10%, with most <5%. High Hg level

samples were analyzed in multiple replicates. Recoveries

of LCS were mostly between 95% and 105%.

2.1.4. Analysis of High Hg Concentration Samples

Considering the representative of sample aliq uots and the

Figure 1. Sample introduction.

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A Pilot Survey of Mercury in Drugs, Cosmetics and Household Products Using Reliable Analytical Methods

258

reliability of weights, generally the masses of the sample

aliquots should not be less than 0.2 mg. Thus it is impos-

sible to get high level samples analyzed by reducing the

mass of the sample aliquots. For samples with Hg con-

centrations higher than 200 ppm, the Hg0 loaded on gold

traps was leached with concentrated HNO3 in loosely

capped vials at 75˚C in a water bath for 30 min. The

leaching solutions were then analyzed for Hg by SnCl2

reduction/amalgamation/CVAFS [18]. To reduce the cost

for analysis, iodated charcoal (IC) traps (Cebam, Bothell,

UAS, or equivalent) were used instead of gold traps for

Hg0 collection for high Hg level samples. The Hg0 loaded

on ICT was leached with concentrated HNO3 in loosely

capped vials at 80˚C in a water bath for 3 hours followed

by SnCl2 reduction/amalgamation/CVAFS [18] for ana-

lyzing Hg.

2.2. Speciation of Hg by Ethylation Based

Method

Samples were extracted with alkaline solutions at 80˚C

for 3 hrs in closed Teflon vials. Hg in aqueous phase

extracts was then speciated using the ethylation based

method described in our previous publication [19-21].

The published method is for simultaneous determination

of methyl and inorganic Hg (MeHg and Hg2+), but here

Hg0 was also collected onto a gold trap that was con-

nected downstream of a Tenax trap (Figure 2). Thus,

ethylated products of MeHg and Hg2+ were collected

onto the Tenax trap, while Hg0 passed through the Tenax

trap and was captured on the gold trap. MeHg and Hg2+

on the Tenax trap were separated and quantified by GC

and CVAFS detection as described by Liang, et al. [19,

20]. Hg0 on the gold trap was measured by CVAFS

against standards generated by Sn2+ reduction [18,22].

Here, the measurement of Hg0 should only be used for

qualitative assessment of the species’ presence because

some amounts of Hg0 may evaporate into the headspace

of the vial during alkaline extraction at 80˚C for 3 hrs,

and then escape to the air when the vial was opened.

Figure 2. Experimental set up for speciation of Hg using

ethylation based method.

2.3. Emission of Hg0 from Skin Creams

Appropriate aliquots of cream samples were weighed on

small pieces of tissue paper, and then the tissues were

placed in glass vials. The vial has an outlet on the cap

(Figure 3). A gold trap was connected to the outlet of the

vial for collecting emitted Hg0. The trap collected emit-

ted Hg for 12 hrs at 20˚C, and then the trap was replaced

with another clean gold trap for collection of another 12

hrs. This cycle can be repeated until Hg0 is emitted com-

pletely. The time length of the periods and how many

periods should be taken depended on Hg concentration,

mass of aliquot, and the experimental purpose. The traps

loaded with Hg0 were measured for Hg0 by CVAFS [18].

Results were calibrated by Hg0 standards generated by

Sn2+ reduction and collected on gold traps [18]. If the

purpose was to measure the total amount of Hg0 emitted

from an aliquot, and the estimated amount of Hg0 was

out of the linearity range of EPA 1631 method, an IC

trap was used instead of the gold trap as described above

(2.1.4) for collection of emitted Hg0 for long enough un-

til Hg0 was emitted completely. The Hg0 loaded on IC

traps was determined using the procedure of 2.1.4.

2.4. Collection of Products

Products were obtained by donations from manufacturers

and individual consumers, and purchased from shops. In

total, 228 samples of various products manufactured in

several countries including USA, France, Germany, and

China (including Hong Kong) were collected and ana-

lyzed. Some of products are shown in Figure 4.

3. Results and Discussion

3.1. Results of THg

All samples were first analyzed for THg using combus-

tion/trap/CVAFS method. Samples found to contain Hg

>200 ppm were re-analyzed using the procedure de-

scribed in the paragraph 2.1.4. Results are listed in Table

1. These formulated cosmetic products are homogeneous

and therefore well suited to this analytical method. This

ensured high quality results for samples analyzed using

the method.

THg was found to be lower than 10 ppb in most prod-

Figure 3. Experimental set up for emission of Hg0 from skin

creams.

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259

3.2. Results of Hg Speciation in High Level Hg

Skin Creams and Drugs

ucts analyzed, which is similar to the concentrations

found in most crude oils processed in the United States

[15]. In about 6% of samples, such as eye cosmetics and

some drugs, THg ranged from 10 ppb to 50 ppb. These

levels generally indicate th at mercury has not been inten-

tionally added to these products. Three skin cream sam-

ples were found to contain THg from 300 to 3000 ppm

and two drug samples from 1 to 4.5 ppm (Figure 5).

Only samples with high THg concentrations were ana-

lyzed for speciation. Five samples, three skin creams and

two western/eastern mixed drugs were analyzed for spe-

cies, MeHg, Hg2+ and Hg0, using the procedure in 2.2,

and results are listed in Table 2.

For the three cream samples manufactured for the use

of skin whitening/shining and anti-speckle, Hg2+ was

found to be about 2% to 3% of THg. The Hg2+ is likely

the fraction oxidized from Hg0 during manufacturing,

storage, or daily opening by consumers. These three

creams had been opened many times by the consumers

prior sending to the lab for analysis. Significant amounts

of Hg0 were found in three creams, indicating Hg0 was

the dominant fraction but this species could not be quan-

Figure 5. High concentration Hg containing skin creams

(left) and drugs (right).

Figure 4. Some of products collected.

Table 1. THg concentration ranges of various products collected and analyzed in this work.

Product Category # of samples THg concentration range, ppmRegulation Limit (RL), ppm Times of exceed RL

Body lotion 16 0.0019 - 0.0054

Liquid soap 15 0.0004 - 0.0011

Solid soap 22 0.0008 - 0.0024

Cosmetic Lotion 23 0.0020 - 2.769* 1 (USFDA) 2.769

Medicinal Lotion 26 0.0004 - 0.0064

Skin Cosmetics 19 0.0020 - 0.0150

Eye Cosmetics 24 0.0020 - 0.0494

Lipsticks 22 0.0026 - 0.0147

Perfume 8 0.0024 - 0.0028

Hair Color 7 0.0056 - 0.0097

Dental Care Iodine 1 0.0212

Western drugs 14 0.0012 - 0.0037 No regulation limits established yet

Western/eastern mixture medicine 31 0.0020 - 4.424* No regulation limits established yet

Total 228

Note, *: US FDA limit of 1 ppm applies to all products regulated under the US Food, Drug, and Cosmetic Act, except for the Act’s allowance of 65 ppm Hg for

eye-area cosmetics. This includes all but the last three product categories in this table. However, the 1 ppm limit does not apply to the last two product catego-

ries in the table. US FDA has published a list of product ingredients, including many Hg compounds, that have been approved in the past, but which are not

allowed in new products “…since there are inadequate data to establish general recognition of the safety and effectiveness of these ingredients for the specified

uses…” (23).

A Pilot Survey of Mercury in Drugs, Cosmetics and Household Products Using Reliable Analytical Methods

260

Table 2. Results of Hg speciation in high level Hg drugs and skin creams.

Sample name Hg, Mean ± SD, ppm

THg Hg2+ MeHg Hg0

Cream-A 2124 ± 81 (n = 5) 46.73 ± 2.29 (n = 3) Not detectable Significant amounts

Cream-B 339.8 ± 12.2 (n = 4) 8.840 ± 0.504 (n = 3 ) Not detectable Significant amounts

Cream-C 2769 ± 21 (n = 3) 80.31 ± 5.78 (n = 3) Not detectabl e Significant amounts

Drug-A 1.235 ± 0.032 (n = 3) 1.217 ± 0.075 (n = 3) Not detectable Not detectable

Drug-B 4.424 ± 0.102 (n = 3) 4.498 ± 0.103 (n = 3) Not detectable Not detectable

tified here for the reasons described above (see paragraph

2.2.). It seems that these creams were likely manufac-

tured by simply mixing Hg0 in creams. MeHg was not

detectable in any produ cts analyzed. In addition t o MeHg,

an ethyl Hg containing compound (thimerosal) has been

using as vaccine preservative, but no vaccine products

were collected, thus ethyl Hg was not measured in this

work.

Most products with elevated Hg have no ingredient

labels and the manufacturer is no t identified on the label.

Generally these products were not traded legally in pub-

lic markets. Consumers often purchased them “under the

table” or through personal relationships. Government

officials have been warning consumers not to use skin

creams, beauty and antiseptic soaps, or lotions that might

contain Hg. However, the use of these products has been

increasing in developing countries, especially in Asian

countries. The products are generally used by women

with darker skin, for example, women in or from Africa,

Middle East, Asia, and Central and South America. A

USFDA web page shows similar products, but no exact

Hg contents in these products were reported [7].

For the tw o drugs , t he Hg2+ was found to be identical to

THg, and no MeHg/ Hg0 were found. The two drugs were

Western/eastern mixture medicine manufactured to alle-

viate the symptoms of colds and allergies, such as nasal

congestion.

3.3. Results of Analysis of Hg0 Emission from

Skin Creams

An aliquot of 5.03 mg of cream A was taken for the Hg0

emission e xperim ent using t he setu p in Figure 3. Hg0 wa s

collected for 30 min on a gold trap, then a new trap was

placed for another 30 min, and then a third trap was placed.

The 3 tra ps were m eas ure d fo r Hg0 and about 34 ng of Hg

was found in each trap, with no significant difference in

Hg amount, indicating Hg0 emitted steadily over the time

under the experimental conditions (Figure 3). According

to this rate, Hg0 contained in this aliquot needs about a

week to be completely emitted. To simplify the analysis,

an IC trap was then used to collect remaining Hg0 for a

week. The trap was then analyzed for Hg using the pro-

cedure described in 2.1.4. The sum of Hg0 collected onto 3

gold traps and the IC trap was calculated to be about 11 µg,

corresponding to 2187 ppm of Hg0 in this sample, close to

the amount of THg found by combustion/trap/CVAFS

method in this sample (2124 ppm). The similarity of the

two concentrations indicates that Hg0 was emitted com-

pletely from the aliquot, and also confirmed the conclu-

sion (Tabl e 2) that Hg in this cream is almost 100% Hg0.

For cream B and C samples, only IC traps were used for

collection of Hg0 emitted from the sample aliquots, and

the amounts of Hg0 were also found to be close to THg

determined by combustion/trap/CVAFS method in these

samples, thus also confirming that Hg in these two creams

is almost 100% Hg0. Some studies conducted to date have

found calomel (Hg2Cl2) in skin lightening creams [4]. In

creams analyzed in this work, the presence of calomel

could be ruled out since the Hg0 concentrations were

found to be equivalent to THg concentrations in these

products.

According to the emission rate (5.03 mg cream emitting

34 ng of Hg0 to air at 20˚C in a 30 min period) , if a pers on

applies 1 g of cream A on their face, then about 160 µg of

Hg0 would be em i tted to air o ver 12 hrs. Meanw hil e som e

of Hg0 would be absorbed through the skin and further

into the blood stream, posing a risk to human health. It is

worth noting that the 160 µg of Hg0 emission was esti-

mated at 20˚C without ai r fl o wi ng, thus the act ual amount

at human face temperature with air flow and open envi-

ronment should be higher than 16 0 µ g.

4. Conclusion

Some dru gs and cosm etics are found t o contain hi gh levels

of Hg that are potentially toxic to consumers. These high

Hg level products are manufactured in developing coun-

tries, but spread in the world thro ugh different legitimate

and gray market/black market channels, making it diffi-

cult to regulate import and sale of the products. Consum-

ers need to know that Hg has been added and is potentially

toxic, and regulations need to be established to govern

manufacturers, perhaps to ban the use of Hg in products.

Open Access JCDSA

A Pilot Survey of Mercury in Drugs, Cosmetics and Household Products Using Reliable Analytical Methods 261

Manufacturers and government regulatory agencies may

need to test cosmetic and pharmaceutical products for Hg

concentrations. Robust and cost-effective methods such as

the methods used in this work should be employed to

ensure high quality results. USFDA regulations already

ban import and sale of these products but they get into the

United States anyway. What mechanisms to ban world-

wide manufacture and distribution would be effective?

How can we effectively educate women about the danger

of these products and change the idea that lighter skin is

better? The desire for lighter skin drives the manufacture,

sale, and use of these products.

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