- If you are not yet a Down To Earth subscriber, please click here to subscribe: Subscription
- If you are an existing Down To Earth subscriber, please log in to download digital archives.
Chemical pollution in oceans, release of radiation into the atmosphere are some of the human activities that are causing animals to suffer
Do you know that humans are not the only ones developing cancer? Even wild animals suffer from the disease. But the primary reasons for this are human activities, says a study.
Mathieu Giraudeau and Tuul Sepp, two post doctoral researchers at the School of Life Sciences in Arizona State University, and Kevin McGraw, professor at ASU believe that humans are altering environment in a manner that causes cancer in the wild animal population.
They say that since human activities are likely to increase cancer rate in wild animals, there is an urgent need for more research into this topic. “We are changing the environment to be more suitable for ourselves and these changes are impacting many species negatively on many different levels, including the probability of developing cancer,” said Sepp.
Giraudeau and Sepp were supported by a team of international researchers. They examined many previous scientific studies that showed how human activities were affecting animals. Such instances include chemical and physical pollution in oceans and waterways, accidental release of radiation into the atmosphere from nuclear plants and the accumulation of micro plastics in both land and water based environments. Apart from these, exposure to pesticides and herbicides on farmlands, artificial light pollution, loss of genetic diversity and animals eating human food are also known to have caused health issues in animals.
“We recently published several theoretical papers on this topic, but this time, we wanted to highlight the fact that our species can strongly influence the prevalence of cancer in many other species of our planet,” said Giraudeau. The study calls humans an oncogenic species for altering the environment in a manner that is causing cancer in other wild species.
While giving examples, Tuul Sepp said wild species are now more in contact with humans than ever before and this increases their closeness to anthropogenic food sources. Another example the researcher gave was that those wild animals living close to cities and roads can develop cancer as light at night can cause hormonal changes and may lead to cancer.
He also gives example of birds, their hormones that are linked to cancer in humans are affected by light at night. Therefore, the next step should be to study if it also affects their probability of developing tumours.
Meanwhile, the researchers highlight that it is not an easy subject to study mainly due to the difficulty of detecting and measuring oncogenic processes in wild populations.
The study gives the example of alteration of the microbiome community of wild animals due to anthropogenic effects. For instance, birds due to urbanisation, pesticides exposure in honeybees, climate change in lizards and habitat fragmentation in African primate. Although there are multiple factors that are linked to these changes, change in diet is one of the main causes.
These researchers are trying to develop some biomarks to study this issue. They would be measuring cancer prevalence in human-impacted environments and at the same time in more preserved areas for the same species. If it is proved that human are in fact the primary cause of cancer in wild animals, then there is a huge probability that many species are at more risk than we know. “To me, the saddest thing is that we already know what to do. We should not destroy the habitats of wild animals, pollute the environment, and feed wild animals human food. The fact that everybody already knows what to do, but we are not doing it, makes it seem even more hopeless,” said Sepp.
The researcher concludes by saying that there might still be hope in education. So there is a hope that future policy makers or decision makers will be more considerate and aware about the anthropogenic effects on the environment.