According to a recent study conducted at the University of California, Berkeley researchers found that Bisphenol A (BPA), which is a compound like estrogen, is associated with change in levels of thyroid hormone in pregnant women and newborn baby boys.
Normal functioning of thyroid is essential for healthy growth and mental development of fetuses and kids. This study, published in Environmental Health Perspectives journal, threw light on the effects of exposure to BPA on thyroid hormones in newborns and pregnant women.
These new findings reveal the health risks of BPA, which is a chemical, found in plastics, canned food linings, dental sealants and thermal paper receipts, which are coated with a color changing chemical, on exposure to heat.
Study and Analysis
BPA levels of 335 women in urine samples were analyzed by the researches, during their second half pregnancy period. Thyroid levels of pregnant women and few days old children were also analyzed. These participants were a part of study in the Center for the Health Assessment of Mothers and Children of Salinas, led by professor of epidemiology and of maternal and child health in UC Berkeley, Brenda Eskenazi.
It was found that for a BPA level doubling, a decrease was noticed in thyroxin of about 0.13 mcgs per deciliter in pregnant women, which relates to hypothyroid effect. For newborn baby boys, there was a 9.9% decrease in thyroid hormone levels, suggesting a hypothyroid effect. It was not clear as to why there was no association of BPA levels among newborn girls.
What Study Authors say
Lead author of the study, Jonathan Chevrier, who is a research epidemiologist at Center for Environmental Research and Children’s Health, UC Berkeley says “Most of the women and newborns in our study had thyroid hormone levels within a normal range, but when we consider the impact of these results at a population level, we get concerned about a shift in the distribution that would affect those on the borderline,”
“In addition, studies suggest that small changes in thyroid level, even if they’re within normal limits, may still have a cognitive effect.” he adds.
Senior author of the study Kim Harley, an adjunct professor of public health and associate director in CERCH, notes that women in reproductive ages have more than 90% of detectable BPA levels in their urine. He says until we find out more about the effects of this chemical, it is better to be cautious and avoid its exposure to whatever extent possible, especially by the women who are pregnant.