Impurities of concern in personal care products (as of Dec 2006)

WHAT YOU SHOULD KNOW
• Why this matters
• What not to buy
• What you can do

UPDATES
• FDA fails to protect consumers
• Cosmetics with Banned & Unsafe Ingredients
• EWG petition to FDA
• Top 20 brands of concern
• Top 20 companies of concern
• Top ingredients and products of concern

IN-DEPTH ANALYSIS
• Compact for Safe Cosmetics Signers
• Safety in the hands of the cosmetics industry
• Exposures add up

Indeed, it has been demonstrated that nitrosamines are carcinogenic in more animal species than any other category of chemical carcinogen.

...Clearly, it appears that [nitrosamines] can be formed during storage, once a product has been opened.

— U.K. Department of Trade and Industry, Cosmetic contamination study (DTI 1998)

An EWG analysis of government and industry sources (CIR 2003, FDA 2000a,b, UNECE 2004) shows that at least 146 cosmetic ingredients may contain harmful impurities linked to cancer and other serious health impacts (Tables 1 and 2), including 3 of the top 20 most commonly used cosmetic ingredients (Table 3). Our analysis of ingredients in 7,500 personal care products shows that because some of these ingredients are used so widely, the vast majority of products on the market have the potential to be contaminated with impurities. None of these impurities is regulated by the federal government:

• Eighty percent of all products assessed contain ingredients that can be contaminated with impurities linked to cancer and other health problems, including more than 80 percent of all lip balms and baby bath products (Table 1).
• Many common impurities readily absorb through the skin. FDA notes that the carcinogenic cosmetic impurity acrylamide is “rapidly absorbed through the skin” (FDA 2004a); that dioxane, a potential impurity in a wide range of ethoxylated cosmetic ingredients, “readily penetrates animal and human skin” (FDA 2000); and that the common family of impurities called nitrosamines also “penetrate the skin” (FDA 2000a).

Sources and prevalence of impurities. Unwanted impurities in cosmetic products can be manufacturing residuals, breakdown products from cosmetic ingredients, environmental contaminants in the case of plant-derived ingredients, or what are called “unreacted monomers,” the small building blocks of the large polymer ingredients common in cosmetics. Potential health harms associated with impurities can dwarf those linked to the product ingredients themselves, but are mitigated by the typically low levels of impurities in the products.

In their cosmetic ingredient review summaries, the industry safety panel notes concerns over potential impurities for about one of every 10 ingredients assessed. Likewise, in 10 percent of cases for which the panel has recommended concentration limits for chemicals in cosmetics, the limits have been set for impurities, not for the ingredient under review (CIR 2003). Of the four product concerns for which FDA explicitly requests direct contact from imported cosmetic inspectors, three are related to harmful impurities in the products (FDA 2000b).

In a 1998 personal care product testing program, a European government agency found carcinogenic impurities in 43 percent of 128 products tested (DTI 1998), including baby lotion and shampoo, sunscreen, and liquid soap. This study, focused on the family of carcinogenic chemicals called N-nitrosamines, joins other government and industry studies showing that harmful impurities can commonly contaminate cosmetic products (see, for example, CIR 2003 and FDA 2000a,b).

Government and industry sources reveal 24 industrial chemicals or groups of chemicals identified as potential impurities in a wide range of products, with health concerns spanning cancer, neurotoxicity, and reproductive problems (CIR 2003, FDA 2000a,b, UNECE 2004). The certainty of these impurities’ presence in cosmetics ranges widely, from speculation — reflected in the industry safety panel setting limits on residues of arsenic, mercury, PCBs and pesticides in cottonseed acid, for example — to complete confirmation, such as the established presence of carcinogenic nitrosamines in a wide range of personal care products.

Cosmetic industry polices the purity of its own products. Some manufacturers buy ingredients certified by an independent organization called United States Pharmacopeia (USP). These ingredients may contain lower levels of harmful impurities, but the criteria for certification are not public. There are no federal standards for ingredient purity. While is seems likely that some companies purchase or manufacture refined, purified ingredients, it is equally likely that many do not. Consumers and government health officials have no way to know.

Because the purity of cosmetic ingredients is not regulated by federal law, product purity has become a business decision. Companies can weigh the cost of purchasing purified or certified ingredients against the potential liability of selling products that may contain carcinogenic impurities. Liabilities are low: cancer typically has a long latency period, and a doctor can rarely trace the disease back to particular exposures. Although some studies show evidence that actions taken by industry have reduced levels of some impurities over the past 25 years (Matyska et al. 2000), recent testing programs undertaken by FDA and European agencies show that the use of impure ingredients by the industry is still common (FDA 1996, DTI 1998).

It is clear from a review of ingredient assessment summaries published by the Cosmetic Ingredient Review that the industry panel routinely approves ingredients in the absence of impurity data. In a review of a large class of surfactants called ceteareths, for example, the panel stressed “the importance of purification procedures to remove... impurities” noting that “...in the absence of impurities data, the Panel caution[s] that a Ceteareth preparation should not contain 1,4-dioxane or ethylene oxide which are possible oxidation products” (CIR 2003). In another case the panel assumed industry would limit levels of acrylic acid and methacrylic acid impurities in acrylate polymer ingredients after learning that the impurities have an unpleasant odor, an incentive for industry to keep levels low (CIR 2003).

Two of the impurities commonly found in cosmetic ingredients are discussed below.

1,4-dioxane. The Environmental Protection Agency considers 1,4-dioxane a probable human carcinogen, based of the “induction of nasal cavity and liver carcinomas in multiple strains of rats, liver carcinomas in mice, and gall bladder carcinomas in guinea pigs” (EPA, 2003). In a review conducted in 1982, the Cosmetic Ingredient Review panel noted that the cosmetic industry was aware of the problem of the presence of the 1,4-dioxane in cosmetics and was making an effort to lower or remove 1,4-dioxane in cosmetics (CIR 2003, review of choleth-24). But 18 years later, FDA expressed continuing concerns about 1,4-dioxane, noting its potential to contaminate a wide range of products, its ready penetration through the skin, and the evidence linking it to systemic cancer in a skin painting study (FDA 2000). FDA notes that 1,4-dioxane can be removed “by means of vacuum stripping at the end of the polymerization process without an unreasonable increase in raw material cost” (FDA 2000), but such treatment would be voluntary on the part of industry.

A consumer could identify products with potential 1,4-dioxane contamination by scanning product labels for the common ethoxylated surfactants that may contain the impurity, which according to FDA are identifiable by the prefix, or by the designations, of 'PEG,' 'Polyethylene,' 'Polyethylene glycol' 'Polyoxyethylene,' '–eth–,' or '–oxynol–' (FDA, 2000).

Nitrosamines. FDA began analyzing personal care products for the carcinogenic impurities known as nitrosamines as early as 1979. In tests of 300 products between 1979 and 1980 the agency identified a nitrosamine called N-nitrosoethanolamine (NDELA) at levels up to 150 parts per million (ppm). The agency published a notice in the Federal Register of April 10, 1979 (44 FR 21365) warning the cosmetics industry that products containing nitrosamines may be considered adulterated and subject to enforcement action. In a testing program 12 years later, the agency found that maximum levels had dropped 50-fold, to three ppm (Matyksa et al. 2000). And in a European agency study published in 1998, maximum levels of total N-nitroso compounds, including NDELA and related chemicals, had fallen to less than one ppm (DTI 1998).

Despite the apparent reduction in nitrosamine levels achieved by industry over the past quarter century, FDA remains concerned about nitrosamine impurities, because of the solid evidence linking these chemicals to cancer, and because of their ready absorption through the skin:

FDA has urged cosmetic manufacturers to voluntarily remove from cosmetics any ingredient which may combine with others to form NDELA and to conduct additional testing to determine why cosmetics become contaminated with NDELA.

— USFDA Office of Cosmetics and Colors, 1996

According to scientists from San Jose University, the common nitrosamine impurity NDELA “is readily absorbed through the skin and accumulates in organs, such as the liver, bladder, etc. where it induces chronic toxic effects” (Matyska et al. 2000). The International Agency for Research on Carcinogens has found that nitrosamines are carcinogenic in all animal species studied, including primates. No other carcinogen has been found to be carcinogenic in as many species as nitrosamines. (IARC, 1978; 1982; 1985; 1987).

It may be the case that industry has developed methods to lower nitrosamine levels in newly-manufactured products, but recent studies suggest that industry's persistence in using nitrosamine precursors in a wide range of products guarantees that the products will become contamined with nitrosamines during a period of normal use, as the precursors react with other chemicals to form nitrosamines. Our analysis shows that one of every 10 products on the market contains ingredients that can combine with other chemicals to form nitrosamines. Notably, a study sponsed by the U.K. Department of Trade and Industry found that nitrosamine levels in some products had more than doubled four months after the product was opened, and increased by more than four-fold over 17 months (DTI 1998).

Breast cancer and impurities. EWG's assessment of product ingredient labels and data on cancer-causing chemicals identified three common impurities in personal care products that are linked to mammary tumors in animal studies — ethylene oxide, PAHs, and 1,3-butadiene. The ingredients for which these impurities are of concern are used in one of every four personal care products on the market (Table 4).

Among girls born today, one in eight is expected to get breast cancer and one in 30 is expected to die from it (NCI 1996, 1997, 2000). A review by scientists from Lawrence Berkeley National Laboratory shows that as many as one of every five chemical carcinogens causes mammary tumors in laboratory studies, indicating that the breast is more sensitive to carcinogens than almost any other tissue in the body (Gold et al. 1991). EWG's identification of three impurities linked to breast cancer does not represent a full accounting of possible mammary carcinogens in personal care products. Instead, it is a partial accounting based on the National Toxicology Program's assessment of mammary carcinogens (NTP 2000) and other sources in the peer-reviewed literature. Further study would likely identify additional ingredients in personal care products that raise concerns with respect to breast cancer.

• PAHs. PAHs, or polycyclic aromatic hydrocarbons, are common contaminants in petrolatum, also called petroleum jelly and sold under well-known brand names like Vaseline. Petrolatum is found in one of every 14 products on the market (7.1 percent of the products assessed by EWG), including 15 percent of all lipstick and 40 percent of al baby lotions and oils. FDA restricts petrolatum in food to no more than 10 parts per million, and requires petrolatum used in food packaging or drugs to meet impurity restrictions for PAHs (21 CFR 178, 21 CFR 172.880). But the agency allows any amount of petrolatum of any purity in personal care products, many of which are applied directly to the lips and swallowed. Manufacturers would find no legal impediments to using the same unregulated petrolatum in personal care products as can be used in shoe polish.

  Among the studies linking the petrolatum impurity PAHs to breast cancer is a Columbia University study in which researchers found that the breast tissue of women with breast cancer was 2.6 times more likely to contain elevated levels of PAHs bound to DNA (called DNA adducts) than the breast tissue of women without breast cancer (Rundle et al. 2000). The National Toxicology Programs finds that some PAHs are reasonable anticipated to be human carcinogens, and the State of California lists a number of PAHs as carcinogens in its Proposition 65 program (NTP 2002, OEHHA 2004).

  Petrolatum is listed as a probable human carcinogen in the European Union's Dangerous Substances Directive (UNECE 2004), and its use in cosmetics will be banned by September 2004 with the following caveat: “The classification as a carcinogen need not apply if the full refining history is known and it can be shown that the substance from which it is produced is not a carcinogen.” Chemical industry sources have interpreted this clause to mean that petrolatum will continue to be allowed in cosmetics in the EU if it is refined and meets PAH purity standards for food set by FDA (Faust and Casserly 2003). Even this purity standard does not set direct limits on PAH content, but instead relies on a light absorption test as an indirect indicator of contamination.

  In the U.S. no requirement for refinement applies for petrolatum in personal care products. Some manufacturers likely choose refined petrolatum low in PAHs, but perhaps some do not. Product labels do not uniformly show the “USP” certification on the petrolatum listing in EWG's ingredient label database, and in any event, the certification criteria for a USP listing are not public. Some product labels include the term “skin protectant” in parentheses after the petrolatum listing, an indication that the petrolatum has been refined and meets FDA requirements for drug applications. But in most cases a consumer buying a product containing petrolatum has no way to know if the ingredient is low in carcinogenic PAHs or not.




• Ethylene oxide. Ethylene oxide can be an impurity in one of every four personal care products on the market, judging from the prevalence of the common ingredients associated with ethylene oxide impurities (ethoxylated surfactants). Ethylene oxide shows “clear evidence” of carcinogenicity in the mammary glands of both male and female test animals, according to the National Toxicology Program (NTP 2000).

  Ethylene oxide would be expected to occur in tandem with the carcinogenic impurity 1,4-dioxane, also a residual contaminant in common personal care product surfactants. According to FDA, a consumer could identify products with these potential contaminants by scanning product labels for the common ethoxylated surfactants that may contain the impurity, identifiable by the prefix, or by the designations, of 'PEG,' 'Polyethylene,' 'Polyethylene glycol' 'Polyoxyethylene,' '–eth–,' or '–oxynol–' (FDA, 2000).

  The industry's safety panel, the CIR, routinely raises the spectre of ethylene oxide impurities in its safety reviews, but in nearly every case lacks the data that would allow for an assessment of health concerns. In their review of product ingredients known as oleths, the panel merely noted its concerns about ethylene oxide in its review findings: “Of concern was the possible presence of 1,4-dioxane and ethylene oxide impurities. The importance of using the necessary purification procedures to remove these impurities was stressed” (CIR 2003).

  In another case, the CIR was provided data from industry showing that ethylene oxide levels in cosmetic ingredients called nonoxynols range up to 12.2 parts per million. The panel compared the dose of ethylene oxide estimated from cosmetics exposures against allowable daily doses for people exposed to the same chemical as a residue on medical equipment, from a private standard-setting body called the International Organization for Standardization. Finding the estimated dose from cosmetics to be lower than the allowable dose from medical equipment, the panel then determined that “the use of a cosmetic product only in excessive amounts could yield [the] level of exposure” found to be of concern for medical devices (CIR 2003). This, the panel's most rigorous assessment of ethylene oxide occurrence in cosmetics, relies on safe doses derived from a private organization setting voluntary standards for medical equipment.

  Ethylene oxide is fairly volatile and might be easily stripped from ingredients in purification processes. FDA notes that its companion impurity 1,4-dioxane “may be removed from ethoxylated compounds by means of vacuum stripping at the end of the polymerization process without an unreasonable increase in raw material cost” (FDA 2000). Such a process would also likely removed ethylene oxide, but no such treatment is required for personal care product ingredients. Levels of ethylene oxide are not restricted in products, so consumers have no ability to know if they are purchasing items free of ethylene oxide or not.




• 1.3-butadiene. 1,3-Butadiene is a potential impurity in butane (also called n-butane), a propellant used in aerosol personal care products (CIR 2003). CIR's safety review of butane in personal care products fails to mention the potential for 1,3-butadiene impurities, but in the EU, butane will be banned from use is cosmetics by September 2004 if impurity levels exceed 0.1 percent. 1,3-Butadiene shows “clear evidence” of carcinogenicity in the mammary glands of both male and female test animals, according to the National Toxicology Program (NTP 2000), and is listed as an ingredient in 198 personal care products assessed by EWG.

 

Table 1. Products that may be contaminated with impurities.

9,747 (76.8%) products may be contaminated with impurities. Showing top 20 product categories, ranked by prevalence.

Category	Percent of Products
Varicose/Spider Vein Treatment	100.0% (9)
Hair Color and Bleaching	98.1% (156)
Bubble Bath	97.4% (74)
Shaving Cream	96.2% (51)
Shampoo	96.2% (607)
Baby Wipes	95.0% (19)
Depilatory	94.3% (50)
Baby Sunscreen	93.8% (15)
Baby Shampoo	92.6% (25)
Mascara	92.5% (196)
Body Wash/Cleanser	91.8% (515)
Liquid Hand Soap	91.0% (81)
Baby Lotion	90.9% (30)
Sunless Tanning	90.5% (95)
Hair Spray	90.1% (127)
Hand Sanitizer	90.0% (9)
After Sun Product	89.7% (26)
Anti-aging	89.1% (197)
Moisturizer	88.4% (1047)
Sunscreen/Tanning Oil	87.4% (250)

 

Table 2. Products that may be contaminated with impurities, by impurity type.

Impurity Group	Percent of Products
HYDROQUINONE	34.5% (4,380)
FORMALDEHYDE	25.3% (3,215)
ETHYLENE OXIDE	21.7% (2,751)
1,4-DIOXANE	21.7% (2,751)
NITROSAMINES	11.3% (1,435)
ACRYLAMIDE	6.2% (785)
PAHS	5.8% (733)
METHACRYLIC ACID	4.3% (545)
ACRYLIC ACID	4.3% (545)
2-ETHYLHEXYL ACRYLATE	4.3% (545)
LEAD	3.6% (452)
ARSENIC	3.5% (439)
PESTICIDES	2.9% (362)
HEAVY METALS	2.6% (324)
PCBS	2.2% (284)
OXAZOLIDINE	2.2% (277)
MERCURY	1.9% (243)
GOSSYPOL	1.9% (243)
BUTADIENE	1.7% (221)
DIOXIN	1.5% (196)
CHLOROFORM	1.5% (196)
ORGANOCHLORINES	1.3% (161)
GLYCERYL DIESTERS	1.3% (170)
DEGRADED CARRAGEENAN	1.4% (178)
FREE ETHANOLAMINES	1.1% (146)
GAMMA SULTONE	0.8% (105)
N-BUTYL ALCOHOL	0.6% (77)
ACETAMIDE MEA	0.6% (71)
METHOXYETHANOL	0.3% (37)
ETHOXYETHANOL	0.3% (37)
BENZENE	0.3% (37)
BENZO(A)PYRENE	0.3% (32)
PROGESTERONE	0.0% (1)

 

Table 3. Top 20 ingredients with impurity concerns, by prevalence of use.

Ingredient	Impurity Concern(s)	Percent of Products
TOCOPHERYL ACETATE	HYDROQUINONE	24.9% (3,166)
TOCOPHEROL	HYDROQUINONE	12.1% (1,534)
DIAZOLIDINYL UREA	FORMALDEHYDE	10.9% (1,381)
COCAMIDOPROPYL BETAINE	NITROSAMINES	9.3% (1,179)
PEG-STEARATES	ETHYLENE OXIDE, 1,4-DIOXANE	7.9% (997)
DMDM HYDANTOIN	FORMALDEHYDE	7.3% (921)
IMIDAZOLIDINYL UREA	FORMALDEHYDE	5.6% (713)
PETROLATUM	PAHS	5.5% (694)
CETEARETH-20	ETHYLENE OXIDE, 1,4-DIOXANE	4.1% (515)
POLYQUATERNIUM-10	ACRYLAMIDE	3.4% (436)
ACRYLATES COPOLYMER	2-ETHYLHEXYL ACRYLATE, ACRYLIC ACID, METHACRYLIC ACID	2.8% (361)
COCAMIDE DEA	NITROSAMINES	2.3% (286)
POLYQUATERNIUM-7	ACRYLAMIDE	2.0% (253)
D&C RED 6	ARSENIC, ARSENIC, GOSSYPOL, GOSSYPOL, LEAD, LEAD, MERCURY, MERCURY, PCBS, PCBS, PESTICIDES, PESTICIDES	1.9% (243)
PEG-7 GLYCERYL COCOATE	ETHYLENE OXIDE, 1,4-DIOXANE	1.9% (240)
AMINOMETHYL PROPANOL	OXAZOLIDINE	1.9% (239)
PEG-8	ETHYLENE OXIDE, 1,4-DIOXANE	1.8% (228)
TRICLOSAN	CHLOROFORM, DIOXIN	1.5% (196)
ALUMINUM STARCH OCTENYLSUCCINATE	ARSENIC, HEAVY METALS, LEAD	1.5% (195)
QUATERNIUM-15	FORMALDEHYDE	1.5% (191)

 

References

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