It's been 30 years since the nuclear disaster at Chernobyl. Now, researchers are taking a look back at how the area has changed and how organisms have responded to the excess of radiation exposure.

When the disaster happened, the V.I. Lenin Nuclear Power Station in the former Soviet Union released radioactive contaminants into northern Ukraine. Airborne contamination, however, spread far beyond the immediate area. In fact, an area that encompasses about 1,000 square miles remains cordoned off.

Because of the unique environment presented, Time Mousseau and Anders Moller of the CNRS have studied the region and inhabitants of the Chernobyl Exclusion Zone since the year 2000. Their scope expanded after Japan's Fukushima disaster in 2011, and they've now established an initiative to look at both areas.

"As a starting point for our studies of animal populations, we took our cue from the medical literature - one of the first effects observed was the presence of cataracts in the eyes of people exposed to energy from atomic bombs," Mousseau said. "And we found that both birds and rodents show elevated frequencies and degree of cataracts in their eyes in the more radioactive areas. Nowadays, we see higher rates of cataracts in flight crews who spend a lot of time in airplanes, which expose them to extra radiation. And people who work in radiology fields are more likely to show increased prevalence and degree of cataract formation in their eyes."

The researchers also found that radiation in Chernobyl decreased brain size and increased the incidence of tumor formation. It also affected fertility and increased the prevalence of developmental abnormalities in birds. The researchers also conducted a meta-analysis of oxidative damage resulting from ionizing radiation.

"One of the messages coming through our research is that this secondary mechanism through oxidative stress appears to be fairly commonly observed," Mousseau said. "We have many examples now, both from other people's research and our own, that shows that there does appear to be some sort of tradeoff between the quantity of antioxidants in the organism's body and its ability to defend itself against the effects of ionizing radiation. Species that can somehow adjust the use of antioxidants may be using this as a means to reduce genetic damage."

The findings are published in the April edition of the journal Science of the Total Environment.