An Investigation of Heavy Metal Accumulation in Liver and Kidney Tissues of the European Hare (Lepus europaeus P.) in Samples Originating from Intensive Agricultural Environments in Hungary

The aim of this study was to evaluate the concentrations of 17 heavy metals measured in the liver and kidney tissues of the European brown hare (Lepus europaeus) as a function of age, sex, organ type, and sampling area. In addition, we assessed the relationships between trace element profiles and reproductive parameters and highlighted their potential relevance from a food-safety perspective. Age-related comparisons revealed significantly higher concentrations of Ti, Fe, Cd, and Hg in adult individuals, whereas no statistically significant differences were detected for the remaining elements. No significant sex-related differences were found for any of the investigated elements. In contrast, the organ-based analysis revealed substantial differences. The concentrations of all elements differed significantly between the liver and the kidney. Correlation analyses identified positive associations between Mn and Zn concentrations, as well as between Mn and Cu concentrations, in both organs. The relationship between Zn and Cd was also positive and statistically significant. A comparison among sampling areas showed no significant spatial differences in the concentrations of Cr, Fe, Cu, and Mo. The greatest spatial heterogeneity was observed for Co, Hg, Pb, and Se, with Se concentrations differing significantly among nearly all sampling areas. Our results indicate strongly overlapping spatial heavy metal profiles, suggesting a gradual rather than sharply differentiated geographical pattern and similar emission characteristics. This interpretation is further supported by the clustering and principal component analysis (PCA) results. PERMANOVA analyses indicated that trace element profiles did not significantly influence the number of placental scars. Furthermore, neither age nor its interaction with trace element profiles exerted a detectable effect on variation in placental scar numbers.