Bioaccumulation of Total Mercury (THg) in Freshwater Fish-Perch (Perca fluviatilis L.) and rudd (Scardinius erythrophtalmus L.)-Human Health Risk Assessment.

Fish have the capacity to bioaccumulate metals such as mercury through the food web, posing potential health risks to aquatic ecosystems and humans. This study aimed to assess total mercury (THg) concentrations in different tissues of freshwater fish and evaluate the potential risk for consumers. Perch (Perca fluviatilis) and rudd (Scardinius erythrophthalmus), representing different trophic levels, were collected from Koronowo Reservoir and Lake Wierzchucińskie Duże in summer and autumn. THg accumulation followed the order: muscle > liver > gills, with significant differences observed between tissues. In perch, THg concentrations were 0.061 μg/g (muscle), 0.037 μg/g (liver), and 0.028 μg/g (gills). In rudd, THg levels were 0.050 μg/g (muscles), 0.034 μg/g (liver), and 0.022 μg/g (gills). The target hazard quotient (THQ) values were below 1, indicating that their consumption does not pose a significant health risk to humans. Estimated safe weekly intake was 1,839 g for perch and 2,249 g for rudd for dorsal muscle.