In an article published on November 1, 2015 by the magazine The Scientist, journalist Kerry Grens reports on chemicals that can cause obesity or metabolic disruption – so called obesogens. Firstly, Grens outlines how researchers, such as Mike Skinner of Washington State University, U.S. and Bruce Blumberg of the University of California, Irvine, U.S., first observed that certain environmental chemicals made mice and rats obese. They tested chemicals known to be endocrine disruptors, such as certain pesticides, bisphenol A (BPA, CAS 80-05-7), and phthalates, and discovered that they induce fat cell formation by binding to nuclear hormone receptors, e.g. estrogen receptors or the fatty acid receptor PPARy. In addition, they observed that the exposed animals’ offspring (second and third generation) were prone to increased adiposity too. Further, Grens notes that several observational studies in humans have found correlations between exposure to such environmental chemicals and increased body mass index (BMI). Apart from diet and physical activity, “environmental exposures to chemicals may be an under-recognized third factor in the [obesity] epidemic,” stated Leonardo Trasande of New York University (NYU) School of Medicine, U.S.. However, potential obesogens are difficult to regulate as there are no randomized, controlled clinical trials to test the effects of environmental chemicals on obesity or other conditions. Finally, Grens presents a list of potential obesogens which includes among others tributyltin (TBT, CAS 688-73-3), diethylhexyl phthalate (DEHP, CAS 117-81-7), and perfluorooctanoic acid (PFOA, CAS 335-67-1).
Kerry Grens (November 1, 2015). “Obesogens.” The Scientist