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Among its devastating effects, bisphenol A (BPA) -- a common plasticizer in food packaging and water bottles -- has been shown to lower sperm counts, damage the uterus and trigger obesity. It appears that exposures to even tiny doses of the hormone-scrambling chemical could pose serious harm.
Such knowledge makes the unveiling of these new studies and stats all the more disturbing:
- Descendants of rats exposed to BPA developed reproductive disease and obesity, according to a study published yesterday. Researchers found that the third generation had "significant increases" in pubertal abnormalities, testis disease, ovarian disease and obesity. Evidence for this so-called epigenetic effect is piling up and beginning to change how people think about environmental exposures. Will it spark more movement on toxic chemical legislation? Either way, get ready to hear more about this phenomenon down the line.
"Your great-grandmothers exposures during pregnancy may cause disease in you, while you had no exposure," Michael Skinner, lead author of the new study, said in a statement.
- As I've reported before, BPA-free doesn't guarantee a safe product. Another new study adds to that concern: Researchers found that low doses of a substitute chemical used in some BPA-free products, bisphenol S (BPS), altered hormones in much the same way as its chemical cousin. Environmental Health News interviewed Cheryl Watson, a University of Texas biochemistry professor and lead author of the study:
"I think we should all stop and be very cautious about just accepting this as a substitute for BPA," Watson said. "And not just BPS. We should question the whole process about how we introduce chemicals into the marketplace without properly testing them first."
- So, what might this hormonal mess be doing to us individually, and as a human race? It's hard to make any definitive links given everything else that has changed over time, including our diets, but scientists are raising some red flags. Sperm counts dropped by 28% and sperm quality by 38% between 2001 and 2011, according to a new Spanish study. Another study, published in December, found French sperm counts fell by a third between 1989 and 2005. The Daily Mail reports:
A ten year-study of more than 200 men found the average concentration went from 72 million spermatozoids per millilitre in 2001 to 52 million/ml in 2011.
The researchers, from the University of Murcia, say the findings are important because previous research has shown that a concentration lower than 40 million/ml makes conception more difficult.
"If the rate of loss we have outlines continues, with an average decline in quality of two per cent per year, the sperm of young men could reach this danger level of 40 million/ml in a very short space of time," said co-researcher Professor Jaime Mendiola.
- Due to a combination of male and female reproductive problems, nearly one in six U.S. couples now struggles to get pregnant. Reuters reports:
Infertility specialist Dr. Sacha Krieg from the University of Kansas Medical Center in Kansas City agreed that infertility rates may be on the rise - possibly due to women waiting longer to try to have children or, more controversially, to the possible effects of environmental toxins.