Phthalate risks, phthalate regulation, and public health: a review

As a result of concerns about the toxicity of phthalates to humans, several expert panels were convened toward the end of the 1990s to evaluate the implications of the scientific evidence for the risks of phthalates to humans of all ages. These panels concluded that the risks were low although they had concerns about specific applications of some phthalates, e.g., in medical devices. These groups identified data gaps and recommended additional studies on exposure and toxicity be conducted. In light of the additional data, reevaluations of the risks of phthalates were conducted. While these assessments were being undertaken, U.S. state governments and European authorities proposed and promulgated regulations to limit the use of certain phthalates, i.e., di-n-octyl phthalate (DnOP), di-isodecyl phthalate (DIDP), di-isononyl phthalate (DINP), butylbenzyl phthalate (BBP), dibutyl phthalate (DBP), and diethylhexyl phthalate (DEHP), especially in consumer products to which children are exposed. Very recently, similar regulations were promulgated in the United States under the Consumer Product Safety Improvement Act of 2008. This article summarizes recent evaluations of the risks of these phthalates, and addresses the public health implications of the regulations that were enacted. The analysis considers biomonitoring studies and epidemiological research in addition to laboratory animal evidence. Analysis of all of the available data leads to the conclusion that the risks are low, even lower than originally thought, and that there is no convincing evidence of adverse effects on humans. Since the scientific evidence strongly suggests that risks to humans are low, phthalate regulations that have been enacted are unlikely to lead to any marked improvement in public health.