Poly- and perfluoroalkylated substances (PFASs) in water, sediment and fish muscle tissue from Lake Tana, Ethiopia and implications for human exposure.
Lake Tana is Ethiopia's largest lake and there are plans to increase the harvest of fish from the lake. The objective of this study was to assess the levels of poly- and perfluoroalkyl substances (PFASs) in different compartments of the lake (water, sediment, and fish muscle tissue), and its implications for human exposure. The results showed higher PFAS concentrations in piscivorous fish species (Labeobarbus megastoma and Labeobarbus gorguari) than non-piscivorous species (Labeobarbus intermedius, Oreochromis niloticus and Clarias gariepinus) and also spatial distribution similarities. The ∑PFAS concentrations ranged from 0.073 to 5.6 ng L-1(on average, 2.9 ng L-1) in surface water, 0.22-0.55 ng g-1dry weight (dw) (on average, 0.30 ng g-1dw) in surface sediment, and non-detected to 5.8 ng g-1wet weight (ww) (on average, 1.2 ng g-1ww) in all fish species. The relative risk (RR) indicates that the consumption of fish contaminated with perfluorooctane sulfonate (PFOS) will likely not cause any harmful effects for the Ethiopian fish eating population. However, mixture toxicity of the sum of PFASs, individual fish consumption patterns and increasing fish consumption are important factors to consider in future risk assessments.
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE-750 07, Uppsala, Sweden. Electronic address: lutz.ahrens@slu.se.
Lutz
L
Ahrens
Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia.
Habiba
H
Gashaw
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE-750 07, Uppsala, Sweden.
Margareta
M
Sjöholm
Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia.
Solomon Gebreyohannis
SG
Gebrehiwot
Department of Zoological Sciences, Addis Ababa University, Ethiopia; Department of Biology, Hawassa University, P.O. Box 5, Hawassa, Ethiopia.
Abebe
A
Getahun
Department of Biology, Hawassa University, P.O. Box 5, Hawassa, Ethiopia; Department of Earth Sciences, Uppsala University, Villavägen 16, 75236, Uppsala, Sweden.
Ermias
E
Derbe
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE-750 07, Uppsala, Sweden; Department of Earth Sciences, Uppsala University, Villavägen 16, 75236, Uppsala, Sweden.
Kevin
K
Bishop
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE-750 07, Uppsala, Sweden. Electronic address: staffan.akerblom@slu.se.
Staffan
S
Åkerblom
D017738:Alkanesulfonic Acids / Q000032:analysis*; D000818:Animals; D004781:Environmental Exposure; D004784:Environmental Monitoring; D005002:Ethiopia; D005399:Fishes / Q000145:classification; D005466:Fluorocarbons / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D019015:Geologic Sediments / Q000737:chemistry*; D006801:Humans; D060106:Lakes / Q000737:chemistry; D009132:Muscles / Q000737:chemistry*; D017747:Seafood / Q000032:analysis*; D014867:Water / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
D017738:Alkanesulfonic Acids; D005466:Fluorocarbons; D014874:Water Pollutants, Chemical; D014867:Water; C076994:perfluorooctane sulfonic acid
Bioconcentration factors (BCF); Human risk; Per- and polyfluoroalkyl substances (PFASs); Perfluorooctane sulfonate (PFOS); Sediment/water partition coefficient (K(d)); Spatial distribution