Bisphenol A (BPA) is the base chemical used to make several plastic containers, cans and dental sealants. Evidence from animal studies has suggested several potential biological effects of BPA, including estrogenic activity, liver damage, thyroid hormone dysfunction, and obesity-promotion.
To examine associations between urinary BPA concentrations and health in a human population, a one-third random subset (1455) of participants in the US National Health and Nutrition Examination Survery (NHANES) supplied urinary samples for BPA and creatinine levels. The main outcome measures studied were diagnoses of a chronic disease, together with blood markers of liver function, glucose homeostasis, inflammation and lipid changes.
Higher urinary concentrations of BPA were associated with cardiovascular diagnoses even after adjustment for age, sex, and traditional risk factors (p=0.001). Higher BPA concentrations were also associated with diabetes (p<0.001) but not with other common diseases. However, higher BPA concentrations were also associated with clinically abnormal concentrations of gamma-gluamyltransferase (p<0.001) and alkaline phosphatase (p=0.02).
These findings challenge our basic assumptions on the safety of commonly used chemicals and also suggest that it is time to find ‘greener’ alternatives to BPA. Governments across the globe will now be pressured to follow the lead of Canada, which has declared the chemical a major environmental contaminant, and enforced action to limit its human and environmental exposure. However, the possibility that consuming the contents of these plastic bottles is the causative factor, and the BPA a marker of intake, is also feasible.
- Lang IA, Galloway TS, Alan Scarlett A, et al. Association of urinary bisphenol a concentration with medical disorders and laboratory abnormalities in adults. JAMA 2008; 300(11):1303-1310.
- vom Saal FS, Myers JP. Bisphenol A and risk of metabolic disorders. JAMA 2008; 300(11):1353-1355.