Assessing Risks from Bisphenol-A

Evaluating human health risks from endocrine disruptors such as BPA is difficult, but animal studies suggest trouble is afoot

Heather Patisaul

DDT: A Lesson From History

If rigorous scientific assessment doesn’t take the lead in deciding the fate of BPA, politics could, as happened with DDT regulation decades ago. That could open doors to long-term uncertainty and discord. The unintended environmental impacts of DDT were eloquently documented in Rachel Carson’s 1962 best selling book Silent Spring, which launched the modern environmental movement. Carson argued that by liberally spraying pesticides in our zealous determination to destroy “pests,” we risked the systemic destruction of our environment and ourselves. No scientific consensus on DDT’s true threat to people was reached, but in the summer of 1972 the EPA’s top administrator, William Ruckelshaus, announced a near ban of the compound anyway.

Nearly 40 years later, the DDT debate is not over. Most countries banned the agricultural use of DDT by the 1990s, but it is still used in many parts of the world to control mosquitoes, especially where malaria, a disease that kills more people than cancer, heart disease or AIDS, is endemic. Whether DDT causes disease or impairs reproductive development remains the subject of investigation and a controversial topic. Many scientists and policy makers are skeptical that it does; others are convinced.

Of course, DDT undoubtedly saved lives, and likely still does. No such case can be made for BPA. It is time to develop a clear and comprehensive strategy for assessing the potential public health consequences of endocrine disruptors such as BPA that may contribute only economic value. Failing to do so may put future generations at unnecessary risk. While the international debate over BPA’s safety continues, we continue to be exposed, not only to BPA, but also to the many compounds like it.

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