'Severe abnormalities' found in Fukushima butterflies

August 14, 2012 - Scientists found unusually small wings and mutations in the legs and antennae of insects collected in May last year, two months after the earthquake and subsequent tsunami struck.

The radiation exposure harmed their genes and the damage could be passed on to future generations, according the journal Scientific Reports.

Contrast: A healthy adult pale grass blue butterfly (top image) and a mutated variety (bottom) with shriveled wings.

It said that 'artificial radionuclides from the Fukushima (No 1) nuclear power plant caused physiological and genetic damage' to pale grass blue butterflies, a common species in Japan.


'Sensitivity (to irradiation) varies between species, so research should be conducted on other animals,' said Joji Otaki, a team member and associate professor at the University of the Ryukyus in Okinawa.

'Humans are totally different from butterflies and they should be far more resistant' to the health effects of radiation, Otaki noted.

Genetically altered: One of the mutated adult pale grass blue butterflies found in Fukushima, Japan

The researchers collected 121 adult pale grass blue butterflies in and outside Fukushima Prefecture in May 2011, two months after the nuclear crisis started.

Abnormalities such as unusually small wings were found in 12 per cent of the total. But the rate rose to 18 per cent in a second generation produced through mating among the butterflies collected and some even died before reaching adulthood.

When second generation butterflies with abnormal traits mated with healthy ones, the rate of abnormalities rose to 34 percent in the third generation, according to the article.

The team collected another 238 butterflies last September and determined that the abnormality rate stood at 28 per cent.