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Volume 88 Issue 20 | pp. 13-16
Issue Date: May 17, 2010

Cover Story

Preservatives Under Fire

Concerns over the cancer-causing potential of commonly used skin and hair care components dog cosmetic ingredient makers
Department: Science & Technology, Business
Keywords: cosmetics, personal care, preservatives, cancer, endocrine disrupters
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LINE OF DEFENSE
Thor technicians develop cosmetic preservative systems at labs in Compiègne, France.
Credit: Thor Group
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LINE OF DEFENSE
Thor technicians develop cosmetic preservative systems at labs in Compiègne, France.
Credit: Thor Group

Preservatives are added to skin creams, shampoos, and eye makeup to protect users from infections, rashes, and other microbial attacks. But critics contend that when consumers select personal care goods from store shelves, they may also be exposing themselves to endocrine-disrupting and cancer-causing agents.

Although preservatives typically account for less than 1% of a product’s content, the fears they have engendered are significant and have influenced product marketers and ingredient suppliers. Some personal care companies have reformulated so they can emblazon labels with “paraben-free,” “formaldehyde-free,” or even “preservative-free” claims. And cosmetic ingredient companies are responding with systems that avoid suspect preservatives.

Many large, established formulators are wary of the trend away from established preservatives. Eric Perrier, executive vice president of R&D at French cosmetics maker LVMH, puts it delicately. “There is a disconnection between what we know and what the consumer knows,” he says. Perrier says he has no problems with preservative ingredients currently approved for use in the European Union. What makes him nervous is the suggestion that cosmetics be formulated without preservatives.

Smaller cosmetics makers also see the value in long-recognized preservatives. Lokesh Jain, senior R&D chemist at Jason Natural Cosmetics, says he believes parabens are effective preservatives. But he does not use them at Jason. “I’m a formulator,” Jain says. “I take my cues from our marketing people. We make products that consumers want.” The firm prefers to make cosmetics with preservatives that are also recognized as food ingredients, such as phenoxy ethanol and sodium benzoate. Jason promotes its Sunbrella sunscreen, for instance, as paraben-free.

Jain may have the tools to do this, but David C. Steinberg, a consultant on cosmetic preservatives, says label claims such as paraben-free and preservative-free promote “unadulterated junk science.” He argues that much of the misinformation is related to the popular nostrum that anything “chemical” is unsafe.

Steinberg contends that a large part of the controversy over parabens, which are esters of p-hydroxybenzoic acid, is related to a misreading of a study that appeared in 2004 in the Journal of Applied Toxicology (24, 5). The study, whose principal author is Philippa D. Darbre, a cancer researcher at the University of Reading, in the U.K., suggested a connection between the use of underarm cosmetics and the presence of parabens in cancerous breast tissue.

For some activists, the Darbre study reinforced existing suspicions about parabens, which include methylparaben, propylparaben, and butylparaben. A San Francisco-based group called Breast Cancer Action encourages consumers to use paraben-free cosmetics and provides a list of companies that offer such products on its website. Even before the Darbre study, BCA led an effort to pressure Avon to seek “safer” alternatives to parabens.

Darbre herself has kept the paraben issue alive with the 2008 publication of a review of paraben esters, also in the Journal of Applied Toxicology (28, 561). In the review she noted “a need to carry out detailed evaluation of the potential for parabens, together with other estrogenic and genotoxic coformulants of body care cosmetics, to increase female breast cancer incidence, to interfere with male reproductive functions, and to influence development of malignant melanoma.”

Another group of preservatives that includes formaldehyde and formaldehyde donors also has come under attack as potentially cancer-causing. In March 2009, a coalition of public interest groups under the banner of the Campaign for Safe Cosmetics took to task makers of 48 baby shampoos and soaps. Among their targets were companies such as Johnson & Johnson, L’Oreal, and Bath & Body Works, whose products contain “the cancer-causing chemical formaldehyde.” The group’s members include the Environmental Working Group and Friends of the Earth.

Speaking for the group, University of California, San Diego, pediatrics professor Sharon Jacob-Soo pointed to data showing that formaldehyde and formaldehyde-releasing preservatives are sensitizers and causal agents of contact dermatitis in children. “It would be prudent to have these removed from children’s products,” she said. Formaldehyde donors include DMDM hydantoin, quaternium-15, imidazolidinyl urea, and diazolidinyl urea.

BOTTLED UP
Preservatives are used in a wide variety of lotions and creams.
Credit: Rhodia
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BOTTLED UP
Preservatives are used in a wide variety of lotions and creams.
Credit: Rhodia

The report had international implications. Within a month of its release, China and Vietnam said they were conducting their own tests on baby products. In the U.S., members of Congress called for Food & Drug Administration investigations, but the agency has not issued any regulations as a result. Sen. Kirsten Gillibrand (D-N.Y.) introduced the Safe Baby Products Act of 2009, which is still in committee.

The debate over preservatives doesn’t affect every personal care product. For instance, sanitizing wipes don’t require preservatives because they contain a high percentage of bacteria- and mold-killing alcohols.

But such products are exceptions, and most others do require preservatives, for a variety of reasons. One is to keep formulas stable on the store shelf and prevent them from smelling bad or turning unpleasant colors, says Douglas Anderson, a microbiologist with a Ph.D. from the University of Minnesota. But the more important reason many personal care potions require preservatives is that contaminated products could bring on skin rashes, eye irritation, or infections in open cuts or wounds.

Problems can occur, says Anderson, who is president of the Egan, Minn.-based contract testing firm ATS Labs, when harmful Pseudomonas or fecal bacteria are on the skin. Then, dipping a finger into a jar of cream or pouring shampoo from a bottle into a cupped hand can contaminate the container’s contents. If people dilute containers of shampoo, liquid soap, or other cosmetics to “stretch” the contents inside, contaminated water can provide another source of infection, Anderson points out.

The European Cosmetics Association, known as Colipa, notes that warm, steamy bathrooms where cosmetics are stored are ideal breeding grounds for bacteria. “Without preservatives, cosmetics would have to be kept cool and would spoil in the same way as perishable food,” the group notes. “Treating cosmetics like fresh food would be very costly and inconvenient for consumers. Installing a refrigerator in the bathroom is not a practical option.”

Regulatory authorities haven’t ignored the brouhaha over preservatives. After the Darbre report appeared in 2004, the European Commission’s Health & Consumer Protection Directorate General formed a scientific committee to review the evidence against parabens. The committee’s opinion, issued in early 2005, found a number of problems with the Darbre study, including the fact that most underarm cosmetics do not contain parabens. It concluded that “there is no evidence of demonstrable risk for the development of breast cancer caused by the use of paraben-containing underarm cosmetics.”

In the U.S., FDA had a similar take on the paraben issue. In a 2007 review, the agency said the Darbre study “did not show that parabens cause cancer, or that they are harmful in any way.” It added that “at the present time, there is no reason for consumers to be concerned about the use of cosmetics containing parabens.”

Parabens and formaldehyde donors are both effective and safe broad-spectrum preservatives, asserts consultant Steinberg. “The alternative to stopping the use of parabens is contaminated personal care products,” he says, adding: “A natural product is not necessarily better than a synthetic product.” Strychnine, arsenic, and poison ivy are all natural materials, but they are not safe for humans, he notes.

If natural alternatives such as plant extracts and essential oils are so good, Steinberg asks, why don’t they appear on Annex VI? The annex is the European Union’s list of preservatives approved for use in products sold in the multistate region. The U.S. does not have a similar list. He estimates it would cost $10 million to $15 million to get a new preservative on the list, and no one, he says, is willing to make that kind of investment.

“Given the number of kilos sold annually, the market is just not big enough to justify such an investment,” Steinberg says. In addition, there is always a risk that the tests may fail to prove efficacy or that critics will attack a new chemical entity, dragging out the approval process and adding to the cost of winning final approval.

Consultants Kline & Co., which tracks specialty cosmetic ingredients, estimates the global market for antimicrobials at 40,000 metric tons per year. But while Industry Manager Anna Ibbotson says preservatives hold the major share in that category, it also includes bacteriostats and antidandruff agents. Kline is just beginning to track “natural” preservatives, and so far it only has data suggesting they are growing faster than traditional antimicrobials, although from a smaller base.

Groups that militate against certain cosmetics ingredients are pushing for government preapproval of all cosmetics, Steinberg says. And if that happens, “you can kiss the cosmetic industry good-bye.” One example of a move in that direction is a recent effort in Colorado to pass the Colorado Safe Personal Care Products Act. The bill, which was withdrawn in March, would have prohibited the sale of cosmetics that contain chemicals identified as causing cancer or having reproductive toxicity.

Products containing harmful chemicals on lists compiled by the Environmental Protection Agency, the International Agency for Research on Cancer, and the National Toxicology Program would have been banned in the state. The bill also would have allowed private citizens to file suit to enforce the act.

Lisa Powers of the Personal Care Products Council (PCPC), which represents major U.S. cosmetic makers, said at the time that the bill would “ban products that are legally marketed under the FDA’s regulations. It is grossly overreaching and lacks any scientific basis.” As a fact sheet from PCPC points out: “Every ingredient has both a safe level and a hazardous level. It is the dose and/or exposure conditions that make a particular ingredient safe or unsafe.”

Steinberg points out that the bill focused on chemicals rather than ingredients. So if a banned chemical appeared in a formulation as a by-product, even at 1 ppt, the maker could be sued. Tongue in cheek, he remarks, “Think of what Colorado would have smelled like with no soap, toothpaste, deodorants, and shampoos.”

The Campaign for Safe Cosmetics, which lobbied for passage of the Colorado bill, lamented its demise. The group attributed the end of the bill to “aggressive lobbying” from PCPC and opposition by industry stalwarts such as Johnson & Johnson, Estée Lauder, and Mary Kay. “It was a good fight,” the group concluded. “We garnered a lot of media buzz and public attention.” Safe personal care products “is an issue that is being fought all over the country, and it will not disappear in Colorado.”

Most personal care ingredient makers assert the safety and effectiveness of traditional preservatives, but they are nonetheless acceding to customer demands for natural alternatives. “The public is not really informed,” says Andrea Wingenfeld, preservation technical business manager at International Specialty Products. “There is a lot of misleading information on the Web,” she adds. “Why would you want to claim a product is preservative-free? Such a claim could make a consumer think the product is unsafe.”

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As for concerns about parabens and formaldehyde donors, Wingenfeld points out that these and other synthetic preservatives are listed on Annex VI. “They are all well-defined chemically and have been extensively tested for toxicity.” ISP supplies preservatives that include parabens and formaldehyde donors.

In fact, Wingenfeld asserts, chemical preservatives are safer than their natural counterparts because the latter are often not clearly defined and can contain impurities that may cause allergic reactions. It is true, she says, that some preservatives on the EU’s approved list can evoke an allergic response in some individuals, but the point is that “natural ingredients are not necessarily safer than synthetics. There is a lot of marketing hype over what is green and natural,” she says.

Justified or not, many consumers consider naturally derived ingredients to be less toxic and more beneficial to the skin, and cosmetic scientists are trying to make them happy. A search by Chemical Abstracts Service finds that out of 109 applications for cosmetic preservative patents filed in 2009, 65 were for natural preservatives. So far this year, of 33 such applications, 16 were for natural preservatives.

In ISP’s case, the company is developing synthetics that are bioidentical, meaning they are identical to compunds found in nature, yet are man-made. Last year, the firm brought out Optiphen MIT Ultra, a broad-spectrum blend of the synthetic preservative methylisothiazolinone and phenylpropanol, a molecule found in flowers and fruit. Wingenfeld says the inclusion of synthetic phenylpropanol in the blend “provides an option that is one step closer to the all-natural preservative the market is looking for.”

Some firms, like Campo Research, a Japanese-owned natural cosmetic materials provider, are rooting for the naturals market to grow. The company has a line of preservatives based on the honeysuckle flower that offer antimicrobial properties, claims Muthurakuwodeyar Balasubramaniam, the firm’s vice president. Sold as Plantserve, the honeysuckle derivative has skin-regenerating, wound-healing, and antidandruff properties as well, he says.

Campos’ alternative preservative is expensive, Balasubramaniam acknowledges: roughly $50 per lb, versus a few dollars for parabens. Plus, Plantserve is not listed on the EU Annex VI.

Not many preservative ingredients are as inexpensive as parabens, points out Laura Szymczak, a marketing manager with Arch Chemicals. For customers who want an effective natural preservative system, the firm’s Biovert antimicrobial is an effective, though higher priced, alternative. It mimics the mammalian metabolic process that inhibits and kills invading microbes in tears, saliva, and milk, Szymczak says.

Arch’s protective system works in a pH range of 4 to 6, whereas traditional preservatives generally work in a much broader range. One advantage Biovert offers formulators, Szymczak says, is that products made with it can be designated “preservative-free.” Biovert does not appear on Annex VI, but its ingredients are internationally accepted for cosmetics use, she adds.

“Parabens are the safest preservatives on Earth,” asserts Samir D. Sarvaiya, chief executive officer of India-based Salicylates & Chemicals (S&C), a maker of parabens. But since parabens have come under attack, S&C is also manufacturing a line of essential oils, called Salinaturals, for use as preservatives.

Essential oils are not listed on Annex VI, notes Sarvaiya, who suggests he would be interested in getting them there. In the meantime, his chemists have also developed a preservative blend that combines DuPont Tate & Lyle’s 1,3-propanediol, a corn-derived solvent, with more traditional preservatives such as caprylyl glycol and phenoxyethanol.

In a bid to reduce preservative use, some cosmetic ingredient makers have developed additives to boost their effectiveness. Clariant, for instance, has developed Velsan SC, which it promotes as a natural preservative aid. The synergist in this case is sorbitan caprylate, and it works with a variety of common preservatives such as phenoxyethanol and benzyl alcohol, says Sonja Gehm, global marketing manager. It’s also touted as acting as a solubilizer and skin moisturizer.

Rhodia acquired a line of preservatives and preservative alternatives when it bought specialty surfactants maker McIntyre Group last year. “We are able to offer customers preservative-free options,” says Sébastien Méric, Rhodia’s vice president of home and personal care. In some cases, “you can manipulate pH levels to minimize or eliminate preservatives,” he says.

And although the McIntyre deal gave Rhodia some traditional preservatives, the firm is not promoting them, Meric says. Instead, Rhodia is advising customers to use Mackaderm GCP where appropriate. Sandra Catarino, a Rhodia business development manager, says Mackaderm GCP is a mixture of a rose fragrance and emollient esters with “intrinsic” biocide properties.

Thor Group, a U.K.-based maker of personal care ingredients, supplies a line of traditional preservatives. “Consumers are ill-informed about the safety of preservatives,” says Managing Director Eduardo de Purgly. Yet the firm also offers a range of emollients with preservation boosting properties. “We have two types of customers,” de Purgly says, “those who want traditional preservatives and those who don’t.” He adds, “If customers don’t want preservatives, we have emollients.”

Preservatives consultant Steinberg warns that if formulators avoid the tried and true preservatives, they do so at their own peril. So far, he contends, they have done a good job of preventing bacterial contamination of personal care products. If formulators aren’t careful about cosmetic preservation, “people may get injured,” he warns.

 
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