Humans May Influence Cancer in Many other Species on the Planet
ARIZONA — May 24, 2018
Researchers from Arizona State University's School of Life Sciences have come to the conclusion that human activity contributes to the spread of cancer not only among its own population but also among animals living in their natural environments.
The article was published in the journal Nature Ecology & Evolution, as was reported in a press release on Phys.org
Mathieu Giraudeau and Tuul Sepp, both postdoctoral researchers in the lab of ASU life sciences professor Kevin McGraw, say that humans are changing the environment in a way that causes cancer in wild animal populations.
In the paper, Giraudeau and Sepp and a team of international researchers, point out many pathways and previous scientific studies that show where human activities are already taking a toll on animals. These include chemical and physical pollution in our oceans and waterways, accidental release of radiation into the atmosphere from nuclear plants, and the accumulation of microplastics in both land- and water-based environments. In addition, exposure to pesticides and herbicides on farmlands, artificial light pollution, loss of genetic diversity and animals eating human food are known to cause health problems.
In addition, Sepp said: "It is already known in human studies that obesity and nutrient deficiency can cause cancer, but these issues have been mostly overlooked in wild animals. At the same time, more and more wild species are in contact with anthropogenic food sources. In humans, it's also known that light at night can cause hormonal changes and lead to cancer. Wild animals living close to cities and roads face the same problem—there is no darkness anymore. For example, in birds, their hormones—the same that are linked to cancer in humans—are affected by light at night. So, the next step would be to study if it also affects their probability of developing tumors."
According to the authors, Homo sapiens can be defined as an oncogenic species, although it is still unknown how much the development of our civilization causes the formation and spread of cancer in wild species.
Cancer occurs in all species that have been studied by humans, including bare diggers, which were previously considered immune to cell division failures leading to neoplasms. At the same time, there is no data on morbidity in different animal populations, which makes it difficult to assess the impact of human activity.