Oxidative stress biomarkers, metal(loid)s and persistent organic pollutants in European hedgehogs: An integrated approach to environmental contamination

Environmental pollution is a growing concern, posing a significant threat to the ecosystem health. The European hedgehog (Erinaceus europaeus) is considered a suitable bioindicator for monitoring metal(loid)s and persistent organic pollutants (POPs), such as polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) or polycyclic aromatic hydrocarbons (PAHs). However, physiological responses to these pollutants remain understudied. In this study, oxidative stress biomarkers (catalase, glutathione S-transferase and malondialdehyde production) in liver and kidney of 70 European hedgehogs from Northwest Spain were assessed. Moreover, As, Hg, Cd, and Pb concentrations in hair, spines, liver and kidney were measured, and POPs including PCBs, OCPs and PAHs, were measured in adipose tissue. Metal(loid) interactions between tissues were estimated along with the relationships between oxidative stress biomarkers and endogenous factors such as age and sex. Mercury was the most abundant metal in all tissues, exceeding critical thresholds (8.09, 14.0, 5.3 and 3.1 mg kg^-1 dw in hair, spines, kidney and liver). PAHs, PCBs and OCPs were detected in 57, 28 and 15 % of the samples, respectively. All metal(loid)s in hair and spines were significantly correlated with organs, as well as oxidative stress biomarkers with Cd, Hg, Pb, and POPs. Our results describe the oxidative status of hedgehogs, and the observed correlations suggest that the levels of contaminants found in the animals may be associated with oxidative stress responses. Moreover, the correlations observed between metal(loid) levels in hair and spines with internal organs suggest that these keratinized tissues serve as reliable indicators of internal metal burden.