Frogs in Chernobyl are adapted to withstand high radiation

In 1986, the Chernobyl nuclear disaster released the largest amount of radioactive material into the environment in human history. This was a disaster for all forms of life, but researchers still do not fully understand how the accident affected wildlife in Ukraine today. A new study published in the journal Biology Letters shows that for oriental tree frogs (Hyla of the east), chronic exposure to radioactive environments does not appear to change their lifespan, according to IFL Science.

With the absence of humans, the Chernobyl exclusion zone became one of the largest natural reserves in Europe. “I think the current amount of radiation in the Chernobyl exclusion zone is not enough to cause obvious damage in wildlife, at least in most of the area,” said study author at the Estación Biológica de Doñana institute, Pablo Burraco, said.

During two weeks of working in several highly radioactive areas (for several hours every day), the research team accumulated the same amount of radiation as a person going to the dentist. That’s because the most dangerous radioactive isotopes released at the time of the Chernobyl accident have very short half-lives, so the amount of radiation decreases rapidly after a few months or years.

Burracco is part of a research team led by Germán Orizaola. They conducted field research in Chernobyl from 2016 to 2018, examining animal populations with a special focus on eastern tree frogs. They sampled the frog population at Chernobyl with the full range of radioactive contamination in the area, collecting more than 200 male frogs. In a laboratory setting, they assessed the age of the frogs, the amount of radiation they absorbed, their levels of the stress hormone corticosterone, and determined how well they were aging, using telomere length. Telomeres are structures that help protect chromosome ends from external influences.

As a result, there is no difference in lifespan, aging rate and stress index in tree frogs in Chernobyl compared to frogs living in areas without radiation, proving that the amount of radiation in the area is no longer enough to cause damage. chronic injury. According to the research team, this result strengthens the role of the Chernobyl exclusion zone as a wildlife sanctuary. Low levels of radiation are now key, but frogs are also adapted to survive high levels of radiation. A previous study revealed how they evolved melanism, changing from green to black to protect their bodies from radiation.

Researchers hoped to continue work to best assess the current impact of the Chernobyl accident on wildlife but had to pause due to the Russia-Ukraine war.