Lead, pesticides, brominated flame retardants, plastic additives, polychlorinated biphenyls (PCBs), and heavy metals. This is what researchers at Lund University in Sweden found when they collected dead hedgehogs to investigate the environmental pollutants found in urban environments.
Previous research has investigated the presence of heavy metals in hedgehogs from other urban areas in Europe and found similarly elevated levels of heavy metals. However, the team weren't expecting so many other pollutants.
"What surprised us was that there were so many different environmental pollutants in the animals, such as PCBs and several different phthalates, and that there were very high concentrations of certain heavy metals, especially lead," says Maria Hansson, ecotoxicologist at Lund University and the person who initiated the study.
The Lund researchers are, to their knowledge, the first to find evidence of hedgehog exposure to PAHs, phthalates and pesticides through analyses of liver tissue.
Environmental fingerprint
Urban green spaces attract many species of wildlife but also contain a range of unsustainable synthetic materials and chemicals. Because hedgehogs travel long distances - in and out of parks and gardens every night - and eat insects and other invertebrates, they are particularly exposed to high concentrations of environmental pollutants. When researchers in Lund wanted to learn more about the chemicals and pollutants found in urban areas, using the hedgehog as a study subject was therefore a natural choice. The objective was to understand what risk factors the different pollutants pose to animals in urban environments, and also to ourselves.
"Analysing hedgehogs provides us with a kind of environmental fingerprint of what is in an area's ecosystem. Such knowledge is very difficult to access, but the hedgehogs have enabled us to gain a unique insight into what kind of urban environmental pollution we have directly around us," explains Maria Hansson.
Roadkill hedgehogs were examined
