In 2011, the Fukushima nuclear power plant in Japan experienced a meltdown after the facility was hit by a powerful tsunami, the result of a large earthquake. Now, over three years later, researchers have discovered that food sources for wildlife around the area are still contaminated, causing higher rates of death, illness and disease among butterflies in particular.
The meltdown released large amounts of dangerous radiation into the area, and officials were forced to evacuate over 300,000 people from the region. There were no reports on the negative impact of radiation on humans. However, radiation affected the local wildlife and also the food sources and habitat of the animals.
In this new study, researchers from the University of Rukyus, Okinawa, Japan, chose contaminated leaves from six areas around the power plant, from 36 miles away and from over 1,000 miles away. They fed these leaves to pale blue grass butterflies common in the area.
The researchers found that after the butterflies ate the contaminated leaves, the creatures were negatively impacted by radiation. Those that ate leaves from closer to the Fukushima facility were seriously impacted with health issues that ranged from severe abnormalities, illness and even death. However, butterflies that ate leaves from further away still had radiation doses that caused some issues, such as oddly shaped wings.
"Wildlife has probably been damaged even at relatively low doses of radiation, and our research showed that sensitivity varies among individuals within a species," says Professor Joji Otaki, one of the researchers.
The second part of the study looked at the offspring of the butterflies that ingested contaminated leaves. These consisted of two groups: the ones eating contaminated food and the ones eating uncontaminated food.
The results showed that those eating contaminated leaves suffered from even greater negative effects than did their parents. However, those eating uncontaminated leaves were healthier, with only smaller wings as a side effect.
"Our study demonstrated that eating contaminated foods could cause serious negative effects on organisms," says Otoki. "Such negative effects may be passed down the generations. On the bright side, eating non-contaminated food improves the negative effects, even in the next generation."
An earlier study also focused on feeding butterflies radiation-contaminated leaves. This recent study, however, used leaves with lower doses of radiation, although the radiation levels still often proved lethal.
Currently, Fukushima's most pressing concern is radioactive water. Officials estimate that it will take decades before the cleanup is complete.
