Bioaccumulation and Biota-Sediment Accumulation Factor of metals and metalloids in edible fish: A systematic review and meta-analysis in Ethiopian surface waters.

Abstract Bioaccumulation and Biota-Sediment Accumulation Factor are used to quantify the bioaccumulation of contaminants from water and sediment to biota due to uptake through all possible routes of exposure. The present study aimed to determine the BAF and BSAF of metals and metalloids in different surface waters of Ethiopia. Furthermore, the ecological and human health risks were also examined. Generally, 902 peer-reviewed papers from 2005 to 2022 were searched using search engines. The most common types of edible fish species in studied surface waters of Ethiopia were Nile tilapia (Oreochromis niloticus), African sharp tooth catfish (Clarias gariepinus) and African big barb (Barbus intermedius). A higher concentration of dissolved metals and metalloids were detected in the dry than rainy season. The concentration of metals and metalloids in sediment were higher than in water. The concentration of metals and metalloids in carnivorous fish were relatively higher than in herbivorous fish. The BSAF of Se in all fish species was greater than 1. Oreochromis niloticus was a bio-concentrator of AS and Se. The concentration of Cu, Cd, Pb, and Ni in water environmental threshold values given by EEPA and OECD, and in sediment Cu, Pb, Ni, Zn and Cr were above TEC values and Cd, Ni and Cr were above PEC levels when compared to the United States Consensus-Based Sediment Quality Guidelines for freshwater which indicates that these metals may pose risk to aquatic organisms. Consumption of raw water, except contaminated with Cd, Pb, and Ni and fish muscle, except contaminated with Cd, As, and Cr may not pose risk to consumers. However, local consumers who live close to each freshwater ecosystem may become more exposed to health risk hazards. The findings of this study will provide baseline information on BAF and BSAF of metals and metalloids in surface waters and will contribute to the effective monitoring of environmental quality.