Smarter Living: Chemical Index
Paraben preservatives are widely used in makeup, moisturizers, shampoos and conditioners, and shaving products but they have hormone-like activities and questions remain about whether they are safe.
Parabens are chemicals that slow down the growth of mold in personal care products, pharmaceuticals, and foods. The seven commonly used parabens in cosmetics are methyl, ethyl, propyl, isopropyl, benzyl, butyl, and isobutyl varieties. Two of these--methyl paraben and propyl paraben--are used as preservatives in foods.
The detection of parabens in human breast tumors sparked a controversy over whether parabens, which are common in under-arm deodorants, could cause breast cancer. Parabens can mimic the action of estrogen, a female hormone that contributes to breast cancer growth. This estrogen-like activity is considered weak, but combined exposures to estrogenic chemcicals are of concern because longterm exposure to estrogens is linked to hormone-dependent cancers. A study funded in part by the cosmetics industry has found seven parabens to be safe at the levels currently used in consumer products, but more research is being done.
Parabens may decrease sperm quality, according to results from animal studies. However, the chemicals did not cause birth defects. Many people report allergic reactions to paraben-containing products.
Most Americans are exposed to these chemicals. A 2005-2006 study found methyl paraben and propyl paraben in more than 90 percent of urine samples collected from a representative sample of Americans, and ethyl paraben and butyl paraben in about 50 percent.
The most likely routes of exposure are by eating paraben-containing foods or by absorbing paraben-containing products applied through the skin and scalp. Following exposure, these chemicals are excreted from the body within hours.
Avoiding parabens is difficult because they are in so many personal care products. Many underarm deodorants and antiperspirants no longer contain parabens, but check the label to be sure. You can look up products at the Environmental Working Group's Skin Deep Cosmetic Safety Database. USDA Certified Organic foods may not contain parabens. However, personal care care products are not regulated by this standard and "organic" cosmetics and personal care products can contain anything, so check the labels before you buy. If you are in doubt, ask the manufacturer.
Until more is known about the estrogen-like activity of this family of chemicals, few steps will be taken to regulate it. Support scientific research on hormone-like chemicals.
last revised 12/27/2011