It is well-documented that obese children are at a greater risk of continuing obesity in adulthood. Epidemiological studies have examined the association between BPA exposure and obesity in adults, but fewer studies have been done with children and infants. In the United States, upwards of 92% of people 6 years and above have detectable levels of BPA in their urine. Children and infants are believed to have higher BPA intake for several reasons, including having more repetitions in their exposure intakes (food, drink, air) per pound than their adult counterpart. A 2013 study found an association between urinary concentrations of BPA and body mass indexes of children and adults aged 6–19 years. Obesity was not correlated with exposure to any other environmental phenols such as those found in soaps or sunscreens. This finding strengthens the association between BPA and obesity. Although several associations have been discovered, the molecular mechanisms linking BPA exposure and obesity are not yet known; however, cell-based in vitro studies have been performed to develop a better understanding. Different expressions of BPA in different parts of the body may account for variations in bisphenol A effects. For instance, BPA has been found in high concentration in the placenta, explaining reports of high bisphenol accumulation in this tissue. (A B …show more content…
Environmental Protection Agency reported that over one million pounds of BPA are released into the environment annually. BPA can enter the environment either directly from chemical, plastics. coat and staining manufacturers, from paper or material recycling companies, foundries who use BPA in casting sand, or indirectly leaching from plastic, paper and metal waste in landfills or ocean-borne plastic trash. Despite a soil half-life of only 1–10 days, BPA's ubiquity makes it an important pollutant; It was shown to interfere with nitrogen fixation at the roots of leguminous plants associated with the bacterial symbiont Sinorhizobium meliloti. A 2005 study conducted in the US had found that 91–98% of BPA may be removed from water during treatment at municipal water treatment plants. Nevertheless, a 2009 meta-analysis of BPA in the surface water system showed BPA present in surface water and sediment in the US and Europe. According to Environment Canada in 2011, "BPA can currently be found in municipal wastewater. [...]initial assessment shows that at low levels, bisphenol A can harm fish and organisms over time. BPA affects growth, reproduction, and development in aquatic organisms. Among freshwater organisms, fish appear to be the most sensitive species. (A B Cryer,