Informed consumers can then affect the market through their purchasing choices, but the removal of concerning chemicals from products takes a long time, and it’s not always immediately clear that replacement chemicals are safer. For instance, the BPA in “BPA-free” water bottles and canned foods has been replaced by bisphenol S (BPS), which has a very similar molecular structure to BPA. The potential adverse health effects of these replacement chemicals are now being examined in experimental and epidemiologic studies.
Through its National Health and Nutrition Examination Survey, the Centers for Disease Control and Prevention has reported detection rates of between 75% and 99% for different EDCs in urine samples collected from a representative sample of the U.S. population. In other human research, several EDCs have been shown to cross the placenta and have been measured in maternal blood and urine and in cord blood and amniotic fluid, as well as in placental tissue at birth.
It is interesting to note that BPA’s structure is similar to that of diethylstilbestrol (DES). BPA was first shown to have estrogenic activity in 1936 and was originally considered for use in pharmaceuticals to prevent miscarriages, spontaneous abortions, and premature labor but was put aside in favor of DES. (DES was eventually found to be carcinogenic and was taken off the market.) In the 1950s, the use of BPA was resuscitated though not in pharmaceuticals.