“Our study is the first to show that BPA can alter thyroid function of pregnant animals and their offspring in a long-gestation species with similar regulation of thyroid function as humans” said Catherine Viguié, PhD, of Toxalim, Research Centre in Food Toxicology in Toulouse, France and lead author of the study.
Background Bisphenol A (BPA) and polyfluoroalkyl chemicals (PFCs) are suspected endocrine disrupting compounds known to be ubiquitous in people’s bodies. Population disparities in exposure to these chemicals have not been fully characterized.
Methods We analyzed data from the 2003-2006 National Health and Nutrition Examination Survey. Using multivariable linear regression we examined the association between urinary concentrations of BPA, serum concentrations of four PFCs, and multiple measures of socioeconomic position (SEP): family income, education, occupation, and food security. We also examined associations with race/ethnicity.
Results All four PFCs were positively associated with family income, whereas BPA was inversely associated with family income. BPA concentrations were higher in people who reported very low food security and received emergency food assistance than in those who did not. This association was particularly strong in children: 6-11 year-olds whose families received emergency food had BPA levels 54% higher (95% CI, 13 to 112%) than children of families who did not. For BPA and PFCs we saw smaller and less consistent associations with education and occupation. Mexican Americans had the lowest concentrations of any racial/ethnic group of both types of chemicals; for PFCs, Mexican Americans not born in the U.S. had much lower levels than those born in the U.S.
Conclusions People with lower incomes had higher body burdens of BPA; the reverse was true for PFCs. Family income with adjustment for family size was the strongest predictor of chemical concentrations among the different measures of SEP we studied. Income, education, occupation, and food security appear to capture different aspects of SEP that may be related to exposure to BPA and PFCs and are not necessarily interchangeable as measures of SEP in environmental epidemiology studies. Differences by race/ethnicity were independent of SEP.
SourcesSocial disparities in exposures to bisphenol A and polyfluoroalkyl chemicals: a cross-sectional study within NHANES 2003-2006, Environmental Health 2012, 11:10 doi:10.1186/1476-069X-11-10.
2012: French researchers say they have uncovered new risks
Like DES, Bisphenol-A is a synthetic oestrogen with similar to identical effects on the human body. Studies involving self-reporting by patients exposed to DES show an increased risk in many different autoimmune disorders, including autoimmune thyroid disorders – so the results of this BPA study are no surprise!
“Exposure to artificial estrogens such as BPA and DES can change the way the fetus responds to estrogen later in life and may be associated with breast cancer” says Dr. Hugh Taylor, director of the Yale Center for Reproductive Biology.
Bisphenol A, Cigarette smoke, Morning sickness and Alcohol
Pregnancy may be the mother of all guilt trips. But that anxiety doesn’t necessarily end with the birth of a healthy child. Researchers are finding that in utero exposures could be linked with behavioral or emotional problems in young children and increased cancer risk and other problems later in life.
For example exposure to artificial estrogens such as BPA and Diethylstilbestrol ( DES ) can change the way the fetus responds to estrogen later in life and may be associated with breast cancer.