Fukushima radiation still damaging insects

Science : Following the 2011 Fukushima Daiichi nuclear disaster, Joji Otaki of the University of the Ryukyus in Japan and her colleagues ran an experiment in which they fed radiation-contaminated plants to butterfly larvae. Although the larvae exhibited significant effects, including increased incidence of physical abnormalities and lower survival rates, the results were not unexpected because the plants’ radiation levels exceeded 1000 Bq/kg, much higher than the limit of just 100 Bq/kg set by the Japanese government for food intended for human consumption. Now, Otaki’s group has repeated the experiment almost two years later with plant material gathered from locations between 59 km and 1760 km from Fukushima and registering contamination levels between 0.2 Bq/kg and 161 Bq/kg. As expected, as the radiation level increased, the butterflies’ mortality and abnormality rates increased. Even contamination at the relatively low, 100 Bq/kg level was found to harm wildlife. However, that finding can’t be extrapolated to humans because butterflies are likely more sensitive to radiation.