Bird mutations in the Chernobyl exclusion zone
By Sanjida O’Connell
…According to a UN report in 2005, long-term cancers caused by Chernobyl will eventually kill about 4,000 people: an alarming total, but less than predicted. In fact, in an age of “dirty bombs” and nuclear proliferation, Chernobyl functions as a grim experiment into the consequences of extensive nuclear fallout. Although radiation levels have dropped significantly over the 23 years, there are still “hot” regions. Prof Mousseau says that the most contaminated areas measure 300 microSieverts per hour on the Geiger counter, the equivalent of 1,200 times normal radiation levels, or 15 times as much as a chest X-ray. “Long-term exposure would be deleterious,” he adds drily. The real problem, however, is environmental contamination of radionucleotides, caesium, strontium, and plutonium, which have half-lives of 30,000, 29,000 and 24,000 years respectively. Since this means that over that time period, these chemicals will decay to half their previous concentrations, they will contaminate the land for years.
“What you need to worry about is eating the food, because ingestion is the main way that one becomes exposed to radiation poisoning here,” says Prof Mousseau.
And despite the stories about nature thriving in the Chernobyl area, Prof Mousseau is not convinced. The first discovery that he and Prof Møller made was that birds in the fallout zone were suffering increased levels of genetic mutations. The pair examined 20,000 barn swallows and found crippled toes, deformed beaks, malformed tails, irregularly shaped eyes and tumours. Some birds had red plumage where it should have been blue, or blue where it should have been red.
Thanks to the contamination of the food supply, bird species have declined by more than 50 per cent in high-radiation areas. Only a fraction of the swallows are reproducing, and of those that do lay eggs, only five per cent hatch. Fewer than a third of birds survive to become adults. Prof Mousseau and Prof Møller could confirm that these abnormalities were genetic by examining the swallows’ sperm. …
The insects that they feed on are suffering, too. In the most contaminated areas, there are fewer butterflies, bumblebees, grasshoppers, dragonflies and spiders. “The fact that insects, including pollinators, are sensitive to elevated contaminants has a significant impact on the rest of the ecosystem,” says Prof Mousseau. …
