The European Hare ( <i>Lepus europaeus</i> ) as a Biomonitor of Selected Heavy Metal Pollution in the Marmara Region, Türkiye

Abstract Since the early twentieth century, human-induced environmental pollution has reached levels that pose significant risks to the health of living organisms. The Marmara Region, located in northwestern Türkiye, is the most developed region of the country, with its industrial, commercial, tourism, and agricultural sectors holding significant importance compared to other regions. Therefore, the region is heavily affected by pollutant sources from various sectors. The aim of this study is to assess the levels of chromium (Cr), manganese (Mn), copper (Cu), zinc (Zn), arsenic (As), selenium (Se), cadmium (Cd), lead (Pb), and mercury (Hg) residues in the skin and muscle samples of European hares (Lepus europaeus) from the Marmara Region of Türkiye, to evaluate the environmental metal pollution and habitat quality in this region. Significant variations were recorded among the concentrations of heavy metals studied in the selected tissues. The highest average concentrations in the skin were recorded for Cr (8.69 mg/kg), Mn (3.27 mg/kg), Zn (48.37 mg/kg), As (0.07 mg/kg), Se (0.29 mg/kg), Cd (0.39 mg/kg), and Pb (1.12 mg/kg), while the concentrations of Cu (4.59 mg/kg) and Hg (0.03 mg/kg) were highest in muscle tissues. Correlation analyses revealed statistically significant relationships between metal concentrations accumulated in different tissues. The concentrations of Pb (in 27 out of 52 samples, 51.92%), Cd (in all 42 samples, 100%), Cr (in 47 out of 52 samples, 90.38%), and Hg (in 9 out of 52 samples, 16.98%) in the muscles of hares exceeded the maximum permissible limits (hygiene limits) stipulated in the regulations. Additionally, Pearson correlation analysis showed varying degrees of significant correlations among the heavy metals studied in European hares and confirmed the influence of various anthropogenic pollutant sources in the study area.