A review of the occurrence of metals and xenobiotics in European hedgehogs (Erinaceus europaeus)

The European hedgehog (Erinaceus europaeus) is a popular visitor in gardens and recreational areas all over Europe, but hedgehog populations are declining. Research exploring the causes of the decline, including exposure to potentially harmful pollutants and metals, may provide relevant information to improve conservation initiatives to protect this species in the wild. Hedgehogs are ground-dwelling mammals, feeding on a range of different food items such as insects, slugs, snails, and earthworms but also eggs, live vertebrates, and carrion, and therefore come into close contact with pollutants present in their habitats and in their prey. This review investigated published research on the occurrence of metals and pollutants in hedgehogs and found that a vast range of different pesticides; rodenticides; persistent organic pollutants (POPs), including organochlorine compounds and brominated flame retardants (BFRs); as well as toxic heavy metals could be detected in samples from hedgehogs representing different European countries. Due to their ecology, combined with the opportunity to apply non-invasive sampling techniques through the collection of spines as sampling material, we suggest that the European hedgehog is a relevant bioindicator species for monitoring the exposure of omnivorous terrestrial wildlife to potential toxicants in urban and rural environments.