US EPA

This report provides a summary of discussions held at an EPA-sponsored workshop in Research Triangle Park, NC in October, 2012. Workshop participants discussed approaches to improve risk assessment of PBT chemicals in breast milk, data gaps, uncertainties, and suggested solutions. Highlights of the report include suggestions to improve PBT chemical risk assessment to better protect children’s health through addressing a variety of issues. The report also emphasizes the importance of preserving the message that breastfeeding remains the healthiest option for infants despite the presence of environmental chemicals in breast milk.

Persistent, bioaccumulative and toxic (PBT) chemicals have the potential to accumulate in a woman’s fat tissue over many years prior to pregnancy. PBT chemicals can then be released in human milk, and breastfeeding infants can be exposed to these chemicals at a much higher rate than their mothers were. Babies continue to develop after they are born, and periods of development can set the stage for lifelong health. Therefore, being exposed to PBT chemicals either before or after birth is an important consideration in assessing risk, and it is important to accurately assess early life exposures to these chemicals. In many cases, current environmental risk assessment methods do not account for differences between maternal and infant PBT chemical exposures. In order to fully consider the breastfeeding pathway when assessing lifetime or infant lifestage risk from exposures to PBT chemicals, risk assessors need methods to estimate the dose of chemicals an infant receives through breastfeeding based on an average daily maternal dose.

In October 2012, EPA-sponsored a workshop to stimulate ideas and provide a forum to discuss (1) innovative approaches to assessing early life exposure to and potential health effects from PBT chemicals in breast milk, and (2) the challenges involved in developing such approaches. Workshop attendees included experts representing a variety of sectors (e.g., academia, NGOs, federal and state government agencies) and academic disciplines (e.g., PBT chemical toxicology, general toxicology, risk assessment, epidemiology, developmental toxicology) necessary to identify and to evaluate approaches to assess risk to breastfed infants from PBT chemicals in breast milk.

This report provides a summary of the proceedings of a 3-day workshop in which experts in the areas of PBT chemical toxicology, general toxicology, PBPK modeling and risk assessment gathered to discuss approaches to improving the risk assessment of PBT chemicals in breast milk, including data gaps, uncertainties, and suggested solutions.

ICF International. Improving the Risk Assessment of Persistent, Bioaccumulative, and Toxic (Pbt) Chemicals In Breast Milk: Workshop Summary Report. U.S. Environmental Protection Agency, Washington, DC, 2013.