Two Studies Dispute Reproductive Risks of BPA Exposure
A recent study has allegedly linked occupational exposure to bisphenol A (BPA) with high rates of impotence and sexual dysfunction among Chinese men. D. Li, et al., “Occupational Exposure to Bisphenol-A (BPA) and the Risk of Self-Reported Male Sexual Dysfunction,” Human Reproduction, 2009. U.S. and Chinese researchers apparently examined 634 male workers exposed to BPA levels approximately 50 times
higher than those encountered by the average American. According to the study, “compared with the unexposed workers, BPA-exposed workers reported significantly higher frequencies of reduced sexual function within 1 year of employment in the BPA-exposed factories.” In addition, the authors observed a “dose-response relationship… with an increasing level of cumulative BPA exposure associated with a higher risk of sexual dysfunction.”
The researchers have since defended their results against feedback questioning the study’s relevance to the typical consumer. “Critics dismissed all the animal studies, saying ‘Show us the human studies,” stated one author. “Now we have a human study, and this can’t just be dismissed.” See the Los Angeles Times Health Blog, November 10, 2009; The Washington Post and MSNBC.com, November 11, 2009; FoodProductionDaily.com, November 12, 2009.
Meanwhile, an animal study funded by the U.S. Environmental Protection Agency (EPA) has reportedly shown that BPA has no adverse effect on the reproduction function or behavior of female rats. Bryce C. Ryan, et al., “In Utero and Lactational Exposure to Bisphenol A, in Contrast to Ethinyl Estradiol, Does Not Alter Sexually Dimorphic Behavior, Puberty, Fertility and Anatomy of Female LE Rats,” Toxicological Sciences, 2009. After feeding pregnant and lactating rats with BPA doses between 40 and 40,000 times the estimated median amount consumed by humans, researchers concluded that “the lack of effect of BPA on female and male rat offspring after total oral exposure to low doses in our studies is consistent with the lack of adverse effects on growth, vaginal opening, fertility and fecundity of low doses of BPA in several other robust, well designed, properly analyzed multigenerational studies.”
Both Plastics Europe (PE) and the American Chemistry Council (ACC) have welcomed these findings as a “significant development in better understanding the safety of BPA.” As a PE spokesperson was quoted as saying, “Sound scientific review must continue to be the foundation of regulatory assessments and political decisions.” See FoodProductionDaily.com, November 12, 2009.
