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Trash-Free Waters

Microplastics Expert Workshop Report

The EPA Trash Free Waters program convened a Microplastics Expert Workshop (MEW) on June 28-29, 2017 to identify and prioritize the scientific information needed to understand the risks posed by microplastics to human and ecological health. The workshop gave priority to gaining greater understanding of these risks, while recognizing that there are many research gaps needing to be addressed and scientific uncertainties existing around microplastics risk management.  The workshop participants adopted a risk assessment-based approach and addressed four major topics: 1) microplastics methods, including deficits and needs; 2) microplastics sources, transport and fate; and 3) the ecological and 4) human health risks of microplastics exposure.  Workshop participants recommended developed detailed conceptual models to illustrate the fate of microplastics from source to receptor and assess the ecological and human health risks of microplastics, the degree to which information is available for each, and the interconnections among these uncertainties.  The expert panelists did not provide recommendations for specific regulatory or non-regulatory actions to be taken.

This document presents a summary of the expert panel discussion.

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