Scientists studying black mutant frogs in Chernobyl’s exclusion zone have made a groundbreaking discovery that could signal the area’s potential safety for human habitation.
The 1986 Chernobyl disaster, the worst nuclear accident in history, released unprecedented amounts of radioactive material into the environment.
Decades later, eastern tree frogs living near the site have developed black skin, a mutation linked to high radiation exposure immediately after the meltdown.
Black frogs thriving despite radiation
A study co-authored by Dr. Germán Orizaola from the University of Oviedo in Spain revealed that these frogs live as long as their green-skinned counterparts and show no signs of accelerated ageing.
"There does not seem to be any difference in age or ageing processes between the dark and normal-coloured frogs," Dr. Orizaola said.
Melanin, the pigment responsible for their dark skin, provides protection against radiation, but the mutation is associated with the elevated radiation levels immediately following the accident, not current conditions.
Radiation levels dramatically reduced
Over 90% of the radioactive material released during the disaster has decayed, with the most harmful isotopes, such as iodine-131, disappearing within months.
Dr Orizaola noted that some areas within the exclusion zone now have radiation levels comparable to or even lower than natural levels in other parts of the world.
“Big areas of the exclusion zone now maintain radiation levels that are comparable to background radiation in many places globally,” he explained. “Reoccupation of most of the zone by humans should be possible at any time.”
Wildlife flourishing in the exclusion zone
In the absence of human activity, the 1,600-square-mile exclusion zone has become a thriving haven for wildlife. Wolves, lynx, boars, deer, and other species now roam freely, offering unique insights into how ecosystems respond to chronic radiation exposure.
Scientists, including Dr. Orizaola and co-author Pablo Burraco, have captured over 200 frogs from different locations within and outside the exclusion zone to study their ageing processes. The research, published in Biology Letters, used growth lines in their bones and telomere length to determine age and assess cellular ageing.
A unique natural laboratory
Despite evidence that parts of the exclusion zone may now be safe for humans, Dr. Orizaola argues against resettlement. He emphasises the area’s value as a “natural laboratory” for studying the long-term effects of radiation and its importance as a wildlife sanctuary.
"The value of the area as a natural laboratory for understanding radiation and as a key area for nature conservation exceeds its potential for human settlement,” he said. “It should be maintained as a protected nature reserve and a living memory of the accident.”
Legacy of the Chernobyl disaster
The Chernobyl explosion on 26 April 1986 forced over 160,000 residents to evacuate, leaving behind a radioactive ghost town. The exclusion zone extends into Ukraine and Belarus, with radiation levels expected to remain hazardous for generations.
However, wildlife’s resilience within the zone challenges the idea of it being a “dead zone.” Many argue that the area should be designated as a protected reserve for the animals that have established themselves there.
Mutants of Chernobyl
From black frogs to cancer-resistant wolves, Chernobyl’s wildlife continues to adapt in extraordinary ways. Studies like Dr. Orizaola’s provide critical insights into the long-term impacts of radiation on ecosystems, and possibly, the future for human habitation in this once-devastated region.