You are here:
Predicting the fate and transport of per- and polyfluoroalkyl substances (PFAS) in the atmosphere with air quality models
Citation:
D'Ambro, E., H. Pye, C. Allen, K. Talgo, L. Reynolds, R. Gilliam, J. Bash, AND B. Murphy. Predicting the fate and transport of per- and polyfluoroalkyl substances (PFAS) in the atmosphere with air quality models. ITM Conference 2023, Chapel Hill, NC, May 22 - 26, 2023.
Impact/Purpose:
This abstract will be submitted to the International Technical Meeting on Air Pollution Modeling and it's Application (ITM) Conference May 22-26 2023, in Chapel Hill NC. The abstract covers the work done to implement per- and polyfluoroalkyl substances (PFAS) into EPA's flagship air quality model, CMAQ, and analysis of the factors driving atmospheric fate. Conference website: https://itm2023.vito.be/en/programme/timetable
Description:
Per- and polyfluoroalkyl substances (PFAS) are a large class of human-made compounds that have contaminated the environment both near and far from sources. To date, much of the scientific and regulatory focus has been on PFAS in drinking and surface waters, with a paucity of studies on air emissions, transport, and deposition, which is likely to contribute in part to water contamination. Air quality modeling techniques can be used to quantify air concentrations and deposition fluxes to help parse the role of exposure pathways such as direct inhalation and ingestion via contaminated water. We apply the Community Multiscale Air Quality model (CMAQ) version 5.3.2 to a case study in Eastern North Carolina to model the PFAS emissions and transport at fine scale (1 km) from the Chemours Inc. Fayetteville-Works. 26 PFAS with the largest emissions by mass are identified and added explicitly to CMAQ, along with an aggregate “other PFAS” species to represent the balance of the emissions. The Fayetteville-Works site is unique as it is the only fluorochemical manufacturer to our knowledge to provide a detailed accounting of quantified speciated emissions. We evaluate the CMAQ predictions for deposition against existing measurements and investigate the predicted air concentration and deposition throughout the domain, up to ~150 km from the facility. We also perform a series of sensitivity studies to test the robustness of our results against model inputs. Our findings will help inform the level of emissions detail needed from other facilities for accurate future modeling efforts. Disclaimer: The views expressed in this presentation are those of the authors and do not necessarily reflect the views or policies of the U.S. EPA.