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Abstract Besides freshwater ecosystems such as lakes and rivers, estuaries and coastal regions are crucial to the global distribution of per‐ and polyfluoroalkyl substances (PFAS) through the ocean and their impacts and transport throughout the food web. This review includes a comprehensive assessment of the concentration and distribution of legacy and emerging PFAS compounds in living species, such as plants and aquatic creatures, as well as in abiotic components, such as surface water and sediment within estuarine ecosystems. This paper also explores the temporal and seasonal patterns of PFAS emissions, as well as the fate of both long‐ and short‐chain PFAS compounds. Furthermore, it discusses the partitioning behavior, bioaccumulation, and trophic magnification of PFAS in estuarine environments. PFAS are widespread in estuary sediment and surface water, and sediments continue to serve as a significant reservoir for these substances. The temporal trend suggests that the introduction of legislation and the gradual phaseout of some PFAS groups may have led to a decrease in their concentration levels. Elevated levels of PFAS in estuary aquatic animals and their ability to bioaccumulate and biomagnify in aquatic food webs could lead to long‐term negative health effects on the surrounding population and ecosystem.
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Extraordinary levels of per- and polyfluoroalkyl substances (PFAS) in vertebrate animals at a New Mexico desert oasis: Multiple pathways for wildlife and human exposure
Per- and polyfuoroalkyl substances (PFAS) in the environment pose persistent and complex threats to human and wildlife health. Around the world, PFAS point sources such as military bases expose thousands of populations of wildlife and game species, with potentially far-reaching implications for population and ecosystem health. But few studies shed light on the extent to which PFAS permeate food webs, particularly ecologically and taxonomically diverse communities of primary and secondary consumers. Here we conducted >2000 assays to measure tissue-concentrations of 17 PFAS in 23 species of mammals and migratory birds at Holloman Air Force Base (AFB), New Mexico, USA, where wastewater catchment lakes form biodiverse oases. PFAS concentrations were among the highest reported in animal tissues, and high levels have persisted for at least three decades. Twenty of 23 species sampled at Holloman AFB were heavily contaminated, representing middle trophic levels and wetland to desert microhabitats, implicating pathways for PFAS uptake: ingestion of surface water, sediments, and soil; foraging on aquatic invertebrates and plants; and preying upon birds or mammals. The hazardous long carbon-chain form, perfuorooctanosulfonic acid (PFOS), was most abundant, with liver concentrations averaging >10,000 ng/g wet weight (ww) in birds and mammals, respectively, and reaching as high 97,000 ng/g ww in a 1994 specimen. Perfuorohexanesulfonic acid (PFHxS) averaged thousands of ng/g ww in the livers of aquatic birds and littoral-zone house mice, but one order of magnitude lower in the livers of upland desert rodent species. Piscivores and upland desert songbirds were relatively uncontaminated. At control sites, PFAS levels were strikingly lower on average and different in composition. In sum, legacy PFAS at this desert oasis have permeated local aquatic and terrestrial food webs across decades, severely contaminating populations of resident and migrant animals, and exposing people via game meat consumption and outdoor recreation.
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- PAR ID:
- 10531527
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Environmental Research
- Volume:
- 249
- Issue:
- C
- ISSN:
- 0013-9351
- Page Range / eLocation ID:
- 118229
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.envres.2024.118229
