We used brown bullheads (Ictalurus nebulosus) from Milicz Ponds in our study. The authors examined the impacts of age, body length, body weight, and the condition of the fish on concentrations of metals (Cd, Pb, Ni, Cu, and Zn) in their muscle tissue (n=62). The metal contents in muscle tissue increased in the order from Cd < Ni < Pb < Cu < Zn and amounted to 0.0177, 0.0754, 0.1121, 0.1979, 4.7358 mg/kg of wet weight respectively. Also, the bioconcentration factors (BCF) were calculated based on the metal contents in muscle tissue, water and bottom sediment.
The obtained results allow us to conclude that the metal concentrations in muscle tissue decrease with age (for Pb and Zn, the correlation is highly statistically significant, with the p value ≤0.01). A relationship between body length and weight and Zn content (p≤0.01) was confirmed, as well as between the condition of the fish (expressed by Fulton’s condition factor) and Cd and Cu concentrations (p≤0.05).