Chernobyl frogs resist nuclear radiation, overcome rapid aging and stress

A recent study shows that current radiation levels in the Chernobyl exclusion zone do not have a significant effect on the age, stress levels or rate of aging of local wildlife, especially the eastern tree frog.Eastern Gila).

This study, conducted by a team from the University of Oviedo and the Doñana Biological Station, is one of the first to closely examine how chronic low-level radiation affects the physiology of animals in the area, nearly four decades after the infamous nuclear disaster.

Actual wildlife sanctuary

In an effort to understand the long-term effects of radiation on these frogs, a team led by German Orizaola studied more than 200 male frogs with varying levels of contamination at Chernobyl between 2016 and 2018.

These frogs were selected from areas ranging from areas of high radioactivity to control regions without radiation, providing a complete gradient for comparison.

Using telomere length as a biological marker of aging, the team found that these tree frogs did not experience accelerated aging and did not show significant changes in levels of corticosterone, a stress hormone that typically increases in response to environmental challenges.

“I think that the level of radiation currently existing in the Chernobyl exclusion zone is not sufficient to cause significant harm to wildlife, at least in most areas of Chernobyl,” said study author Pablo Burraco. IFLScience. “I’m not surprised by this.”

Moreover, the study results show that the Chernobyl exclusion zone, although damaged by radiation in the past, now functions as a de facto refuge for wildlife due to the lack of human intervention. Over the years, reduced radiation levels and a lack of human intervention have allowed the local ecosystem to support an amazing diversity of fauna, making Chernobyl one of Europe’s largest unintentional nature reserves.

Study of radiation effects on frogs

The frogs’ radiation exposure has been carefully assessed, taking into account both external environmental radiation and internal contamination through isotopes such as cesium in their muscles and strontium in their bones. Burraco emphasized the accuracy of these radiation measurements. job description as “one of the most accurate estimates of absorbed radiation carried out on vertebrate animals at Chernobyl.”

Comparing this exposure to daily doses of radiation from, for example, a routine visit to the dentist, Burraco emphasized that current levels in the Chernobyl exclusion zone are significantly low due to the decay of isotopes, many of which have half-lives that render them inactive internally. several months or years after the accident.

The team’s analysis also examined the aging process of these frogs. Using growth lines on bones (similar to tree rings) to determine age and telomere length as an indicator of biological aging, the study found no link between radiation exposure and age-related decline.

The results reflect previous research at Chernobyl, as well as studies on animals exposed to radiation from Fukushima disaster in Japan, where no significant negative effects on life expectancy were observed.

Long-term effects of radiation

Interestingly, although today’s lower levels of radiation do not affect frogs and other species, researchers are keen to study whether there are other, more complex genetic or transcriptomic changes may occur.

Burraco mentioned earlier studies that observed pigmentation changes in these frogs, such as increased melanism (darker skin), which may have initially helped them resist radiation, providing protective protection against radiation damage. However, it remains unclear whether this adaptation contributes to their resilience.

This study shows that, despite the Chernobyl disaster radioactive In the past, current levels of radiation were not enough to disrupt key biological processes in eastern tree frogs. The researchers hope future studies will deepen our understanding of how wildlife adapts to environments altered by radiation, as well as provide valuable information about the long-term impacts of nuclear disasters on natural ecosystems.

The study was published in the journal Letters in Biology.