WASHINGTON — As a California panel prepares to consider adding bisphenol A to a list of toxic chemicals, a group of 22 scientists is appealing to the state to set a low ceiling for acceptable exposure levels in addition to listing BPA as harmful under Proposition 65.
The currently suggested maximum allowable dose level (MADL) is 290 micrograms of BPA per day. The group of scientists recommend a MADL of no higher than 50 micrograms per kilogram of body weight per day, said Dr. Csaba Leranth of Yale University’s neurobiology and obstetrics, gynecology, and reproductive sciences departments.
If California’s Office of Environmental Health Hazard Assessment (OEHHA) classifies BPA as a harmful substance, it will also have to approve a suggested baseline level of BPA exposure and any product that could expose consumers to more than that amount must be labeled as potentially harmful.
“We believe that setting a MADL that is consistent with current science and is health-protective is urgent and of utmost importance,” says the letter, which also lists 10 examples from recent animal studies showing harmful effects at one-twelfth the dose or less than the proposed California level.
Leranth said his most recent research, among other studies, shows intrauterine exposure to BPA, even in very low doses, does long-term damage to the brains of primate and human babies.
In July 2009, OEHHA’s Developmental and Reproductive Toxicant Identification Committee voted unanimously that BPA did not belong on the Prop 65 list, based largely on the findings from a 2008 report by the National Toxicology Program.
The American Chemistry Council of Wash¬- ington filed a lawsuit in March to prevent the current attempt to add BPA to the list, saying the move amounts to circumventing the state’s scientific proc¬ess by allowing administrative staff to override the decision of a scientific panel from 2009, particularly since no new information or studies will be considered. ACC is concerned that adding BPA to the list, even with a MADL set so high that little to no labeling would be required, will cause fear among consumers and manufacturers, which will lead to deselection of polycarbonate.