A striking degree of abnormal cell growth Mammary tissue of control mice (left) and mice exposed as fetuses to
|A striking degree of abnormal cell growth Mammary tissue of control mice (left) and mice exposed as fetuses to 1,000 mg per kg of mother’s body weight of MEHP, a common ingredient in plastics. (Black bar is 1 mm.) (Credit: Hixon Lab/Brown University)
1,000 mg per kg of mother’s body weight of MEHP, a common ingredient in plastics. (Black bar is 1 mm.) (Credit: Hixon Lab/Brown University)ScienceDaily (Mar. 16, 2012) — Many environmental and public health officials are concerned about the potential health effects of phthalates, which are common chemicals used to make plastics softer and more pliable. In the first study to examine what effect in utero doses of phthalates have on the reproductive system of mice, Brown University toxicologists found that extremely high doses were associated with significant changes, such as a shortened reproductive lifespan and abnormal cell growth in mammary glands.
Female mouse fetuses exposed to very high doses of a common industrial chemical that makes plastics more pliable develop significant reproductive alterations and precancerous lesions as they grow up, according to a new toxicology study conducted at Brown University.
The administered doses of MEHP, the chemical that results when animals metabolize the industrial phthalate DEHP, were much higher than any normal environmental exposure that people or animals would encounter, said Mary Hixon, assistant professor of pathology and laboratory medicine (research) in The Warren Alpert Medical School of Brown University and a study co-author.
"For these doses, you'd have to be eating the plastic or drinking the plastic," she said. "The real risk is probably minimal for most people."
But when toxicologists set out to determine the effect of a chemical on an organism, they often start with atypically high doses and work their way down to the levels where any adverse effects disappear. Until now, no one had done such a study on the effects of exposure to doses of MEHP in adult mice while they were still in utero.