Distribution of perfluoroalkyl substances (PFASs) in water, sediment, and fish tissue, and the potential human health risks due to fish consumption in Lake Hawassa, Ethiopia

Abstract

Due to their global distribution, persistence, bioaccumulative potential and toxicity, perfluoroalkyl substances (PFASs) are considered as hazardous chemicals. Although many studies on PFASs pollution in aquatic environments have been done in the Northern hemisphere, less is known on PFASs pollution in African aquatic ecosystems and the risks they pose to humans through consumption of contaminated biota. The objective of this study was to determine the spatial distribution of PFASs in water, sediment, and fish tissue in Lake Hawassa, Ethiopia, and to investigate possible human health risks due to fish consumption. Among the PFASs detected in water and sediment, perfluorooctanoic acid (PFOA) was the most abundant with mean concentrations of 6.93 ng/L and 0.23 ng/g dw respectively. Long-chained PFASs dominated the PFAS accumulation profiles in fish tissues, with higher concentrations measured in liver compared to muscle tissue. The detected concentrations of PFASs were, however, often similar to those reported in other African aquatic ecosystems. This study showed no potential health risk due to consumption of contaminated fish based on mean concentrations and fish consumption. However, it is expected that peoples who consume more fish (fishermen and local peoples living close to Lake Hawassa) may suffer health risks due to PFASs contamination.