New health concerns have been raised about the plastic chemical bisphenol A (BPA); a study suggests that there is a link between high levels of exposure to BPA and an increased risk of heart disease and diabetes. While the new study doesn't prove a cause and effect relationship, only a correlation, it is the first human survey to follow up on troubling findings from animal studies. The chemical, which is often found in baby bottles, sports water bottles, and other non-recyclable containers, has gotten several waves of bad press in the past few months. A recent experiment showed that extremely high doses of the chemical damage monkeys' brains, and other work
in animals has suggested that BPA has the potential to disrupt normal hormone signalling by mimicking the natural hormone, oestrogen. Such studies have linked the chemical to a wide range of conditions, including low sperm count, altered fetal development, behavioural disorders in children and prostate cancer [Nature News].
The results of the new study showed that
adults with the highest levels of BPA in their urine were more than twice as likely to report having diabetes or heart disease — compared with adults with the lowest levels of the chemical in their urine [NPR]
. However, experts say the new study raises serious questions, but doesn't provide any firm answers about the safety of BPA
. "I am really torn here, because I really believe that BPA has some concerns, but this paper does not prove that," said Dr. Hugh S. Taylor.... "It's sort of classic guilt by association" [HealthDay News].
The study, published in the Journal of the American Medical Association, wasn't enough to change the recommendations of the Food and Drug Administration when an expert panel met today to discuss the chemical.
“A margin of safety exists that is adequate to protect consumers, including infants and children, at the current levels of exposure,” [said FDA scientist] Laura Tarantino [AP].
Last month, the FDA issued a report saying that the amount of BPA that could leach out of the plastic is too small to hurt anyone. However, a separate report from another government agency, the National Toxicology Program, concluded that there is some concern regarding current levels of BPA exposure.
Government toxicology scientists say that to reduce exposure, people can avoid non-recyclable plastic containers that have the number 7 on the bottom; avoid using these plastics in the microwave, and don't wash them in the dishwasher with harsh detergents [AP].