Nov. 29, 2000 (Washington) -- Women of reproductive age should avoid using certain nail polishes, perfumes, and hair sprays containing an ingredient known to cause lifelong reproductive impairments in male rats, a leading environmental advocacy group cautioned Tuesday.
But some experts as well as industry officials say the claims are unsubstantiated.
The ingredient is an industrial chemical that has been used as a plastic softener and solvent in a wide variety of products for more than 100 years. But at a press conference, the Environmental Working Group of Washington called on women of reproductive age to shun cosmetics containing dibutyl phthalates (DBP), a chemical also found in toys, detergents, and food packages among other things.
The warning was based in large part on a recently completed CDC study, in which the investigators found levels of the metabolized compound in women of childbearing age. "From a public health perspective, these data provide evidence that phthalate exposure is both higher and more common than previously suspected," the CDC investigators wrote.
The investigators also speculated that the higher levels in women of reproductive age were due to the use of cosmetics such as perfume, nail polishes, and hair sprays. The extensive use of these products among women in general probably is leading to the inhalation and absorption of this chemical through the lungs, the investigators said.
As yet, there are no data to establish that DBP may contribute to reproductive impairment in human males. But the CDC study established that the chemical might at least represent a risk to pregnant women with a male fetus, Richard Wiles, vice president of research at Environmental Working Group, tells WebMD.
The animal studies have shown that when DBP was administered to male rats, it resulted in damage to the testes, prostate gland, epididymis, penis, and seminal vesicles. "All regulation in the world of toxic substances is based on animal [studies]," he notes.
The Environmental Working Group suggests that the substance may be responsible for the declining sperm count as well as increase in the sexual deformities and testicular cancer that men in the U.S. have experienced during the 1970s and '80s.
Industry representatives disagree. "I think that the animal studies show that there is a definite threshold, but the amount absorbed from cosmetics is so low that there is no exposure threat," Jerry McEwen, PhD, vice president of science for The Cosmetic, Toiletry, and Fragrance Association, tells WebMD.
To design a study capable of determining whether there is a risk to the male fetus would be impossible, adds McEwen. "Phthlates are everywhere," he tells WebMD. "It would be hard to single ? out [one source]."
This uncertainty makes the chance of any immediate regulatory action virtually impossible. Under the current regulations, the responsibility of proving that there is a public health threat from cosmetics primarily falls upon U.S. health authorities rather than the manufacturers.
Still, many experts insist there is no reason to panic. The American Chemical Society, for example, maintains that the Environmental Working Group analysis makes unsubstantiated links between DBP and the adverse health effects in women and their male children.
The exposure rates in the CDC study were more than 60 times below the levels established by the EPA for a lifetime exposure to phthalates, the American Chemical Society notes. An independent expert panel also recently determined that DBP is a minimal concern after evaluating more than 70 studies, the organization says.
But this dispute, like the presidential race, could easily drag on. At present, there are no planned studies to determine whether the DBP animal model is relevant to human males, and the currently accepted exposure rates are now more than 50 years old.
The findings of their study also strongly suggested that an assessment for the health risk posed by DBP should now be conducted, the CDC investigators concluded. "Exposure data for phthalates is critically important for human risk assessment, especially among a potentially susceptible population," they observed.
"We think that human studies for chemicals like DBP should be done prior to their use," adds Jane Houlihan, a senior analyst at the Environmental Working Group. But in the end, it might be up to consumers to determine whether the studies are necessary, Houlihan concedes. There are alternatives to cosmetic products containing DBP, and the ingredient is almost always included on the label, she notes.