Modeling the Global Fate and Transport of Perfluorooctane Sulfonate (PFOS) and Precursor Compounds in Relation to Temporal Trends in Wildlife Exposure
- 12 November 2009
- journal article
- Published by American Chemical Society (ACS) in Environmental Science & Technology
- Vol. 43 (24), 9274-9280
- https://doi.org/10.1021/es901448p
Abstract
A global-scale fate and transport model was applied to investigate the historic and future trends in ambient concentrations of perfluorooctane sulfonate (PFOS) and volatile perfluorooctane sulfonyl fluoride (POSF)-based precursor compounds in the environment. First, a global emission inventory for PFOS and its precursor compounds was estimated for the period 1957-2010. We used this inventory as input to a global-scale contaminant fate model and compared modeled concentrations with field data. The main focus of the simulations was to examine how modeled concentrations of PFOS and volatile precursor compounds respond to the major production phase-out that occurred in 2000-2002. Modeled concentrations of PFOS in surface ocean waters are generally within a factor of 5 of field data and are dominated by direct emissions of this substance. In contrast, modeled concentrations of the precursor compounds considered in this study are lower than measured concentrations both before and after the production phase-out. Modeled surface ocean water concentrations of PFOS in source regions decline slowly in response to the production phase-out while concentrations in remote regions continue to increase until 2030. In contrast, modeled concentrations of precursor compounds in both the atmosphere and surface ocean water compartment in all regions respond rapidly to the production phase-out (i.e., decline quickly to much lower levels). With respect to wildlife biomonitoring data, since precursor compounds are bioavailable and degrade to PFOS in vivo, it is at least plausible that declining trends in PFOS body burdens observed in some marine organisms are attributable to this exposure pathway. The continued increases in PFOS body burdens observed in marine organisms inhabiting other regions may reflect exposure primarily to PFOS itself, present in the environment due to production and use of this compound as well as degradation of precursor compounds.Keywords
This publication has 32 references indexed in Scilit:
- Contribution of Volatile Precursor Substances to the Flux of Perfluorooctanoate to the ArcticEnvironmental Science & Technology, 2008
- A Global Mass Balance Analysis of the Source of Perfluorocarboxylic Acids in the Arctic OceanEnvironmental Science & Technology, 2007
- Modeling Global-Scale Fate and Transport of Perfluorooctanoate Emitted from Direct SourcesEnvironmental Science & Technology, 2006
- Biological Monitoring of Polyfluoroalkyl Substances: A ReviewEnvironmental Science & Technology, 2006
- Atmospheric Chemistry ofN-methyl Perfluorobutane Sulfonamidoethanol, C4F9SO2N(CH3)CH2CH2OH: Kinetics and Mechanism of Reaction with OHEnvironmental Science & Technology, 2006
- Atmospheric Chemistry of Perfluoroalkanesulfonamides: Kinetic and Product Studies of the OH Radical and Cl Atom Initiated Oxidation of N-Ethyl PerfluorobutanesulfonamideEnvironmental Science & Technology, 2005
- Sources, Fate and Transport of PerfluorocarboxylatesEnvironmental Science & Technology, 2005
- Degradation of Fluorotelomer Alcohols: A Likely Atmospheric Source of Perfluorinated Carboxylic AcidsEnvironmental Science & Technology, 2004
- Accumulation of Perfluorooctane Sulfonate in Marine MammalsEnvironmental Science & Technology, 2001
- Global Distribution of Perfluorooctane Sulfonate in WildlifeEnvironmental Science & Technology, 2001