By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency (EPA) announced on May 19, 2022, the availability of the meeting minutes and final report for the March 15-17, 2022, Science Advisory Committee on Chemicals (SACC) virtual meeting regarding EPA’s proposed Screening Level Approach for Assessing Ambient Air and Water Exposures to Fenceline Communities Version 1.0 under the Toxic Substances Control Act (TSCA). According to the meeting minutes and final report, SACC “agreed that the methodological document was well organized and generally well written.” SACC states that it “had difficulty reproducing results that were relevant to understanding and reviewing the document and indicated multiple limitations and uncertainties,” however. SACC suggested the methodology could only be used as part of a tiered approach to evaluate risk to fenceline communities and should not be used to evaluate risks in isolation. The screening level approach may be protective for the specific exposure pathways included, but it may not be protective overall because potential key exposure pathways are excluded and because it does not consider cumulative exposures, multiple source exposures, aggregate exposures, and double/aggregate and occupational exposures from workers living near and working at the facilities. Some SACC members also suggested that additional risk factors, such as stress, poverty, cultural practices, and diet, should be considered for a comprehensive assessment.
The meeting minutes and final report states that the accuracy and/or completeness of the data used to develop the screening analysis were not adequately supported in the document, and SACC decided it did not defensibly represent actual exposure of fenceline communities. Overall, SACC indicated the basis for several model inputs was insufficiently transparent and that, in particular, daily life activities of all communities disproportionately impacted by chemical exposures was missing in this current version. SACC recommended the term “fenceline” be refined to include the characteristics, behaviors, and realities of communities exposed through means that are not dependent on being within a limited radius from a chemical facility. SACC agreed that Version 1 of the screening tool for fenceline communities “is currently not adequate for evaluating potential exposures relevant to tribes, indigenous populations, subsistence lifestyles, cultural practices, or other unique circumstances. The pathways by which people in unique communities are exposed to chemicals of the contaminated areas are much broader than those represented in the current defining criteria of ‘Fenceline Communities.’” To make the tool applicable for any unique community, the meeting minutes and final report state that additional exposure scenarios and relevant data must be applied.
SACC recommended that knowledgeable community representatives “be intrinsically involved for perspective on how such information is applied in a screening endeavor, as well as the relevance and pedigree of values used to inform exposure algorithms, and relevance of default data and assumptions.” Complementary to this process is the need for enhanced and meaningful outreach to “fenceline communities” and all parties interested in these screens. SACC offered specific commentary and suggestions, along with a collection of references. A meeting transcript is available.