Heavy metal content in soil and their bioaccumulation in earthworms (Lumbricus terrestris L.)

The aim of this study was to determine the concentrations of heavy metals (Cu, Fe, Zn, Pb, and Cd) in the soil and earthworm body (Lumbricus terrestris), as well as to estimate the Bioaccumulation Factor (BAF) in these earthworms. Soil and earthworm samples were collected from March to June 2018 across six diverse locations in Kosovo (Mitrovicë, Kishnicë, Kastriot, Barilevë, Drenas, and Lipjan) for laboratory analysis. Heavy metal concentrations were quantified using an Atomic Absorption Spectrophotometer (AAS) Perkin-Elmer model 1100. Results indicated mean concentrations of heavy metals in soils ranging from 0.03 to 0.78 mg/kg for Cu, 70.62 to 264.29 mg/kg for Fe, 18.96 to 82.24 mg/kg for Zn, 0.11 to 0.52 mg/kg for Pb, and 0.03 to 0.42 mg/kg for Cd. In earthworms, mean concentrations were 0.02 to 0.42 mg/kg for Cu, 53.11 to 205.31 mg/kg for Fe, 15.74 to 53.15 mg/kg for Zn, 0.07 to 0.43 mg/kg for Pb, and 0.01 to 0.37 mg/kg for Cd. Statistically significant variations related to locality, substrate, and heavy metal types were observed. The accumulation patterns in earthworms corresponded with soil concentrations, illustrating a potential risk for higher trophic levels in the food chain due to these heavy metals.