When Swedish researchers at Lund University collected and examined dead hedgehogs, they made several alarming discoveries.
The bodies of the small animals contained high levels of heavy metals, PCBs and pesticides.
The researchers aimed to investigate which chemicals and pollutants are present in Sweden’s urban environments. Since hedgehogs consume insects and other invertebrates and roam long distances in densely populated areas each night, they were a natural choice for the study.
– An analysis of hedgehogs gives us a kind of environmental fingerprint of what is in an area’s ecosystem. Such knowledge is very difficult to access, but from the hedgehogs we have gained a unique insight into what kind of urban environmental pollution we have directly around us, says Maria Hansson, ecotoxicologist at the Center for Environmental and Climate Science (CEC) at Lund University.
Hansson and her colleagues enlisted the help of the public, asking people to report any dead hedgehogs they found. They also received animals that had been taken to wildlife rehabilitation centers but had not survived.
In total, the researchers measured the presence of 11 different elements, including several heavy metals, and 48 organic environmental pollutants in the dead hedgehogs.
Lead, PCBs and pesticides
The dead animals were found to have high levels of lead and also contained toxic PCB chemicals, several environmental chemicals used as plasticizers in plastics and rubber, as well as pesticides, brominated flame retardants and elevated levels of other heavy metals.
– This shows that urban environments, where most of us live today, contain a large number of environmentally problematic substances that are known health hazards. These pollutants originate from building materials, plastics, pesticides, air pollution, waste, traffic, vehicles, and even contaminated soil, Hansson continues.
She notes that there is a need for more environmental monitoring of soil and organisms in urban areas – and that people should reduce the use of synthetic materials, chemicals and plastics, as this has a negative impact on nature.
– Today, we want nature in our cities, so we must also reduce the risk of organisms being exposed to the chemicals contained in the materials and products we choose to use.
Humans are also affected
Previous studies from Europe have also shown the presence of heavy metals in dead hedgehogs – but the Swedish researchers are still surprised by the new findings.
– What surprised us in our study was that there were so many different environmental contaminants in the animals, such as PCBs and several different phthalates, and that there were very high levels of some heavy metals, especially lead.
The ecotoxicologist emphasizes that studying how different species are affected by environmental pollutants is a complex process and that it is unclear how the hedgehogs are actually affected by the pollutants.
– But since hedgehogs are mammals just like us, it’s concerning to find substances known to be hormone-disrupting, carcinogenic, or harmful to reproduction in humans. Of course, other organisms are also affected by our pollution, says Maria Hansson.
