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Tags
HERO ID
6589940
Reference Type
Journal Article
Subtype
Supplemental Data
Title
Supplemental data: A global atmospheric chemistry model for the fate and transport of PFCAs and their precursors
Author(s)
Thackray, CP; Selin, NE; Young, CJ
Year
2020
Is Peer Reviewed?
Yes
Journal
Environmental Science: Processes & Impacts
ISSN:
2050-7887
EISSN:
2050-7895
Volume
22
Issue
2
Language
English
Relationship(s)
is a supplement to
6311636
A global atmospheric chemistry model for the fate and transport of PFCAs and their precursors
Abstract
Perfluorocarboxylic acids (PFCAs) are environmental contaminants that are highly persistent, and many are bio-accumulative and have been detected along with their atmospheric precursors far from emission sources. The overall importance of precursor emissions as an indirect source of PFCAs to the environment is uncertain. Previous studies have estimated the atmospheric source of PFCAs using models and degradation pathways of differing complexities, leading to quantitatively different results. We present results from simulations of atmospheric PFCA formation and fate using the chemical transport model GEOS-Chem. We simulate the most up-to-date chemistry available to our knowledge for the degradation of the precursors fluorotelomer alcohol (FTOH), fluorotelomer olefin (FTO), and fluorotelomer iodide (FTI), as well as the deposition and transport of the precursors, intermediates and end-products of the formation chemistry. We calculate yields of C3-C13 PFCAs formed from 4 : 2 to 12 : 2 fluorotelomer precursors and their deposition to the surface. We find that the ratio of long-chain to short-chain PFCAs increases strongly with distance from source regions. We compare our model results to remote deposition measurements and mid-latitude rainwater measurements. The model captures the observed relationship between rainwater abundance and PFCA chain length, as well as the average deposition rates at mid-latitude and Arctic sites, but underestimates the deposition of PFDoA, PFDA, and TFA at mid-latitudes and PFNA at the Devon Ice Cap. We provide estimates of cumulative PFCA deposition globally. We find that given the most recent emission inventory, the atmospheric source of PFCAs is 6-185 tonnes per year globally and 0.1-2.1 tonnes per year to the Arctic.
Keywords
Environmental Studies; Latitude; Iodides; Atmospheric chemistry; Deposition; Emission; Chemistry; Contaminants; Polar environments; Degradation; Computer simulation; Organic chemistry; Intermediates; Rain water; Emission inventories; Atmospheric models; Chemical transport; Precursors; Biodegradation; Emissions; Arctic region
Tags
PFAS
•
Additional PFAS (formerly XAgency)
•
PFDA
Literature Search Update 5/2020
PubMed
•
PFNA
Literature Search
Pubmed
WOS
LitSearch: May 2019 - May 2020
PubMed
WoS
•
PFOA (335-67-1) and PFOS (1763-23-1)
LitSearch: Feb 2019 - May 2020
WoS
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