Yesterday, the U.S. Department of Health and Human Services released a draft report concurring with the conclusions of a scientific panel that there is “some concern” related to neural and hormonal disruptions in humans who are exposed to a chemical compound called bisphenol-a or B.P.A.
B.P.A. is used to manufacture a rigid yet transparent polycarbonate plastic (#7) that is a component in things like the plastic coating for iPods, food can linings, baby bottles and the familiar “Nalgene” type of water bottle. This is significant because the report cites that 99% of human exposure comes through food ingestion, implicating soda cans, water and baby bottles.
The report concludes that in animal studies, there is “clear evidence of adverse effects” on fetus and newborn development in high dose environments. Yet, in lower dosage environments, there is still “some evidence” of disruption to the reproduction of the studied animals and “limited evidence” of developmental disruption especially related to the prostate gland and urinary tract development in male mice. This is due to BPA’s ability to mimic the body’s natural hormone estrogen.
The bottom line is that this plastic, while under scrutiny for the past several years, is now being identified, by government officials, as posing some human risk and requiring further study. The Canadian government yesterday reported that they are nearly ready to declare BPA a human toxin. Official word from Health Canada is still pending.
Because of the properties of the polycarbonate plastic, BPA can leach into the food contained by the plastic, especially when the food has a high acid content (like tomato sauce), is heated (like baby formula), or the container has been washed with harsh cleansers. Polycarbonate plastic has been measured to leach BPA fifty-five times faster when it contains a hot liquid.
This is especially important with polycarbonate baby bottles, since most adults heat baby formula while in the bottle with a microwave or in a saucepan with water, increasing the leaching of BPA into the infant formula. Because of the small size of infants, the exposure risk through the baby bottle is magnified compared to consumption of BPA by an adult, not to mention the disruption to the infant’s development at such critical stages.
So what to do? The plastics known not to leach are #2 HDPE, #4 LDPE and #5 PP. Consider using one of these plastics to hold food and avoid #7 polycarbonate, #6 Polystyrene and #3 Polyvinyl chloride. Only heat foods in a microwave with glass or ceramic containers. As for baby bottles, I guess Mom was right: good old glass is still the time tested standard that is yet to be surpassed.
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