You may not think of them as an essential part of your skin care and cosmetics, but without question skin-care and cosmetics products need preservatives. This is especially true for products that contain plant extracts—just think about how long a bunch of broccoli lasts in your refrigerator before it becomes a mushy, discolored mess.
Whether it is a cleanser, lotion, toner, blush, foundation, or mascara, without preservatives these everyday items would become overloaded with bacteria, mold, and fungus, making them harmful to skin, eyes, and mucous membranes. However, as necessary as preservatives are to the safety of cosmetics, they’ve had their share of woes over the years. For example, back in the early ’90s, it was discovered that when formaldehyde-releasing preservatives (such as 2-bromo-2-nitropane 1-3 diol, or DMDM hydantoin) are combined with amines (such as triethanolamine), something called nitrosamine forms, and nitrosamine (in its various forms) is, in fact, carcinogenic. This problem was viewed as inconsequential for cosmetics because the amount of preservatives used in cosmetics is minute. No test has shown it to cause problems for people applying makeup or using skin-care products. Studies relating to carcinogenic properties of nitrosamine were done by feeding it orally to laboratory rats. Still, it is not a pleasant thought to associate a “carcinogen” with your cosmetics in any way, shape, or form. As a result, and despite their effectiveness, formaldehyde-based preservatives are not as popular as they once were.
Another group of preservatives, called parabens, is now in a predicament similar to that of formaldehyde-releasing preservatives, and this has become a common subject for questions from my readers. These parabens may come in the form of butylparaben, ethylparaben, isobutylparaben, methylparaben, or propylparaben, and they have been linked distantly (meaning in limited studies and with only a handful of subjects or animal studies) to breast cancer due to their weak estrogenic activity and their presence in breast – cancer tumors, as well as to low sperm-count rates in men. But even from a distance that has some people worried, especially considering that, by some estimates, more than 90% of all cosmetics products contain one or more parabens. In fact, parabens are the most widely used group of cosmetic preservatives in the world because of their efficacy, low risk of irritation, and stability.
What started the concern about parabens was a study published in the Journal of Steroid Biochemistry and Molecular Biology, January 2002, pages 49-60, that evaluated the estrogenic activity of parabens in human breast-cancer cells. The very technical findings of the study, which involved both oral administration and injection into rat skin, did show evidence of a weak estrogenic effect on cells in a way that could be problematic for binding to receptor sites that may cause proliferation of MCF-7 breast-cancer cells.
A single study identified parabens in human breast-tumor samples supplied by 20 patients. This study was concerned primarily with the use of deodorants that contained parabens rather than with cosmetics in general, but it has been extrapolated to the cosmetics industry as a whole, prompting many consumers to check the ingredient lists of the products they’re using. But more to the point, the presence of parabens in human breast tumors doesn’t mean they caused the tumors.
Pervasive fear was generated by these well-circulated facts. What didn’t make the e-mail spam rounds is that all the researchers who are studying this issue, as well as health organizations around the world, agree that the information to date is hardly conclusive and at best vague, and that potentially parabens require more study (Sources: Journal of Applied Toxicology, January-February 2004, pages 1-4, September-October 2003, pages 285-288, and March-April 2003, pages 89-59; and Journal of the National Cancer Institute, August 2003, pages 1106-1118).
With regard to deodorants in general, it turns out parabens are rarely used as the preservative. A scientific review paper published in the Bulletin du Cancer, September 2008, pages 871-880, concluded that “After analysis of the available literature on the subject [of deodorants causing cancer], no scientific evidence to support the hypothesis was identified and no validated hypothesis appears likely to open the way to interesting avenues of research.”
On the other side of the coin, there is research showing that parabens are absorbed through intact skin and are not broken down (Source: Journal of Applied Toxicology, July 2008, pages 561-578), but once again the association as to its effect is just not known.
It is also important to realize that parabens are used in food products as well (Source: Food Chemistry and Toxicology, October 2002, pages 1335-1373), which could very well be the source, not cosmetics. What is surprising to some is that parabens actually have a “natural” origin. Parabens are formed from an acid (p-hydroxy-benzoic acid) found in raspberries and blackberries (Source: Cosmetics & Toiletries, January 2005, page 22). So much for the widely held belief that natural ingredients are the only answer for skin-care products!
As yet, no one has any idea (or has evaluated) whether it is the consumption of parabens or their application to the skin that is responsible for their presence in human tissue. And no one knows what the presence of parabens in human tissue means.
In terms of the low male sperm count in relation to parabens, research published in Birth Defects Research, Part B, Developmental and Reproductive Toxicology, April 2008, pages 123-133, concluded that parabens had no effect on sperm count in an in vivo experiment (meaning it was done on real guys).
Does this mean you should stop buying products that contain parabens? I mean who wants this stuff being absorbed through their skin whether there is conclusive research or not? That’s a good question, but the answer isn’t simple and the studies are hardly conclusive on any front. Clearly it is a serious issue, and the FDA is conducting its own research to determine what this means for human health (Source: The Endocrine Disruptor Knowledge Base (EDKB), http://edkb. fda. gov/index. html). But a definitive answer is far from close.
As a point of reference, and just to keep the concern over parabens in perspective, it is important to realize that parabens are hardly the only substances that have estrogenic effects on the body. The issue is that any source of estrogen, including the estrogen our bodies produce or the types associated with plant extracts, may bind to receptor sites on cells, either strongly or weakly. This can either stimulate the receptor to imitate the effect of our own estrogen in a positive way, or it can generate an abnormal estrogen response. It is possible that a weak plant estrogen can help the body, but it is also possible for a strong plant estrogen to make matters worse. For example, there is research showing that coffee is a problem for fibrocystic breast disease, possibly because coffee exerts estrogenic effects on breast cells. (Sources: Journal of the American Medical Womens Association, Spring 2002, pages 85-90; Annals of the New York Academy of Science, March 2002, pages 11-22; and American Journal of Epidemiology, October 1996, pages 642-644.)
To quote some studies directly: “Although parabens can act similarly to estrogen, they have been shown to have much less estrogenic activity than the body’s naturally occurring estrogen. For example, a 1998 study (Routledge et al., in Toxicology and Applied Pharmacology) found that the most potent paraben tested in the study, butylparaben, showed from 10,000- to 100,000-fold less activity than naturally occurring estradiol (a form of estrogen) [found in our water systems]. Further, parabens are used at very low levels in cosmetics. In a review of the estrogenic activity of parabens (Golden et al., in Critical Reviews in Toxicology, 2005), the author concluded that based on maximum daily exposure estimates, “it was implausible that parabens could increase the risk associated with exposure to estrogenic chemicals” (Source: www. fda. gov).
Ironically, the endocrine-disrupting potencies of ingredients like parabens or phthalates (also discussed in this chapter) “are several orders of magnitude lower than that of the natural estrogens” (Source: Environment International, July 2007, pages 654-669). Human endocrine-disrupting sources have their origin in plants, such as marijuana (Source: Toxicology, January 2005, pages 471-488), or in medicines such as acetaminophen (Tylenol) (Source: Water Research, November 2008, pages 4578-4588).
A study conducted at the Department of Obstetrics and Gynecology at Baylor College of Medicine in Houston, Texas, investigated the estrogenic effects of licorice root, black cohosh, dong quai, and ginseng “on cell proliferation of MCF-7 cells, a human breast cancer cell line….” The results showed that “Dong quai and ginseng both significantly induced the growth of MCF-7 cells by 16- and 27-fold, respectively, over that of untreated control cells, while black cohosh and licorice root did not” (Source: Menopause, March-April, 2002, pages 145-150). Another study concluded that “Commercially available products containing soy, red clover, and herbal combinations induced an increase in the MCF-7 [breast cancer] proliferation rates, indicating an estrogen-antagonistic activity….” (Source: Menopause, May-June 2004, pages 281-289). Despite this evidence, when was that last time you read a media report or received a forwaded e-mail about the breat cancer risk from soy or ginseng?
One more point about the risk of breast cancer related to underarm deodorant. In October 2002, a study conducted at the Seattle-based Fred Hutchinson Cancer Research Center, published in the Journal of the National Cancer Institute, looked at the issue of underarm deodorant use and breast cancer. The study compared the use of underarm deodorant in 810 women who had been diagnosed with breast cancer, and 793 women who were not affected by the disease. When the two groups were compared, researchers found no evidence of an increased risk of breast cancer linked to using antiperspirant or deodorant, or using antiperspirant or deodorant after shaving with a traditional razor blade. In short, the researchers believed their study proved there was no link between underarm deodorants and breast cancer risk.