Current and historical concentrations of 22 poly- and perfluorinated compounds (PFASs) in sediment collected from Lake Superior and northern Lake Michigan in 2011 and Lake Huron in 2012 are reported. The sampling was performed in two ways, Ponar grabs of surface sediments for current spatial distribution across the lake and dated cores for multi-decadal temporal trends. Mean concentrations of the sum of PFASs (∑PFASs) were 1.5, 4.6 and 3.1 ng g-1 dry mas (dm) in surface sediments for Lakes Superior, Michigan and Huron, respectively. Of the five Laurentian Lakes, the watersheds of Superior and Huron are the less densely populated by humans, and concentrations observed were typically less and from more diffuse sources, due to lesser urbanization and industrialization. However, some regions of greater concentrations were observed and might indicate more local, point sources. In core samples concentrations ranged from 7 that include perfluoro-n-octane sulfonate (PFOS) bind more strongly to sediment, which resulted in more accurate analyses of temporal trends. Shorter-chain PFASs, such as perfluoro-n-butanoic acid which is the primary replacement for C8 PFASs that have been phased out, are more soluble and were identified in some core layers at depths corresponding to pre-production periods. Thus, analyses of temporal trends of these more soluble compounds in cores of sediments were less accurate. Total elemental fluorine (TF) and extractable organic fluorine (EOF) indicated that identified PFASs were not a significant fraction of fluorine containing compounds in sediment (<0.01% in EOF).

Department of Civil and Materials Engineering University of Illinois at Chicago 842 West Taylor Street Chicago IL 60607 7023 USA

Department of Earth and Environmental Sciences University of Illinois at Chicago 845 W Taylor Street Chicago IL 60607 USA

Environmental and Occupational Health Sciences School of Public Health University of Illinois at Chicago 2121 West Taylor St Chicago IL 60612 USA

Environmental and Occupational Health Sciences School of Public Health University of Illinois at Chicago 2121 West Taylor St Chicago IL 60612 USA; State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences China

Toxicology Centre University of Saskatchewan Saskatoon SK S7N 5B3 Canada

Toxicology Centre University of Saskatchewan Saskatoon SK S7N 5B3 Canada; Dept Veterinary Biomedical Sciences University of Saskatchewan 44 Campus Drive Saskatoon SK S7N 5B3 Canada; Department of Biology and Chemistry and State Key Laboratory in Marine Pollution City University of Hong Kong Kowloon Hong Kong SAR China; Department of Zoology and Center for Integrative Toxicology Michigan State University East Lansing MI 48824 USA; School of Biological Sciences University of Hong Kong Hong Kong SAR China

Toxicology Centre University of Saskatchewan Saskatoon SK S7N 5B3 Canada; Research Centre for Contaminants in the Environment Pavilion 29 Masaryk University Brno Czech Republic

Citace poskytuje Crossref.org