Perfluoroalkyl Acids in Great Lakes Precipitation and Surface Water (2006–2018) Indicate Response to Phase-outs, Regulatory Action, and Variability in Fate and Transport Processes

Abstract

The concentrations of perfluoroalkyl acids (PFAAs) were determined in precipitation from three locations across the Great Lakes between 2006 and 2018 and compared to those in surface water. Perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) concentrations generally decreased in precipitation, likely in response to phase-outs/regulatory actions. In comparison, concentrations of shorter-chained PFAA, which are not regulated in Canada did not decrease and those of perfluorohexanoate and perfluorobutanoate (PFBA) recently increased, which could be due to their use as replacements, as the longer-chained PFAAs are being phased-out by industry. PFOS and PFOA concentrations were greater in Lake Ontario precipitation than in precipitation from more remote locations. In comparison, PFBA concentrations were comparable across locations, suggesting greater atmospheric transport either through its more volatile precursors and/or directly in association with particles/aerosols. In Lake Ontario, the comparison of PFAAs in precipitation to those in surface water provides evidence of sources (e.g., street dust and wastewater effluent) in addition to wet deposition to surface water, whereas wet deposition appears to be dominant in Lakes Huron and Superior. Our results suggest that source control of shorter-chained PFAAs may be slow to be reflected in environmental concentrations due to emissions far from the location of detection and continued volatilization from existing in-use products and waste streams.

Photochemical transformation of perfluoroalkyl acid precursors in water using engineered nanomaterials

“…The broad toxicity profile of PFAAs has led to their being gradually phased out of products in many countries since 2000; however, the concentrations of PFAAs in the environment are still relatively high (Gao et al, 2019, Gewurtz et al, 2019, Routti et al, 2016. This may be due to the decomposition of PFAA precursors (PrePFAAs) resulting in the formation of PFAAs (Nguyen et al, 2013, Peng et al, 2014.…”

A Critical Review of a Recommended Analytical and Classification Approach for Organic Fluorinated Compounds with an Emphasis on Per‐ and Polyfluoroalkyl Substances

“…Some PFAS, mostly PFAAs, certain precursors, PFECAs, or perfluoroether sulfonic acids (PFESAs), are quite mobile and have been reported in multiple environmental and biotic matrices (e.g., drinking water, soil, air, surface or groundwater, precipitation, sediment, human blood, human breast milk, urine, aquatic and terrestrial organisms, plants) (Giesy and Kannan 2001; Ahrens and Bundschuh 2014; Wang et al 2015; Chen et al 2018; Macheka‐Tendenguwo et al 2018; Gewurtz et al 2019; Ghisi et al 2019). The widespread occurrence of nonpolymer PFAS is due to their diverse chemical and physical properties (see above), which determine their environmental fate and transport.…”

“…Due in part to their lower molecular weight, nonpolymer PFAS are more likely to occur in water and air, which leads to their mobility and distribution distant from their point of manufacture, use, or disposal. For example, some of the nonpolymer perfluoroalkyl substances, like PFAAs, exist in their anionic form in water under environmental conditions, making them soluble and mobile in that matrix as demonstrated by their detection in surface water, groundwater, and drinking water (Ahrens and Bundschuh 2014; Chen et al 2018; Crone et al 2019; Gewurtz et al 2019). In addition, per‐ and polyfluorinated substances, especially acids, telomers (acids and alcohols), amides, and amidoethanols, have been measured in the air where they are primarily associated with particles and aerosols (Barton et al 2006; Chen et al 2018; Wang et al 2018; Han et al 2019).…”

Selective extraction of perfluorooctane sulfonate in real samples by superparamagnetic nanospheres coated with a polydopamine‐based molecularly imprinted polymer

“…Methods based on LC combined with MS have been most commonly applied for quantitative determination of PFOS, and LC−MS/MS is regarded as the gold-standard reference method [9]. Concentrations of PFOS at the ppb level or above have been detected in surface water and human serum samples globally [10][11][12][13][14]. In the analytical process, SPE and SPME technology using the commercial or fabricated materials are usually applied to isolate and purify PFOS samples before LC−MS/MS analysis, due to the low analytes content and the complexity of matrices [15,16].…”