The brunt of the disaster is usually borne by the floras inhabiting the contaminated areas since they cannot move. This, however, makes them ideal for studying the effects of ionizing radiation on living organisms. Coniferous plants such as the Japanese red pine and fir have, for instance, shown abnormal branching after the Fukushima disaster. However, it is unclear whether such abnormalities reflect genetic changes caused by the prevailing low-dose-rate radiation in the area.

To address this concern, a team of researchers from Japan developed a rapid and cost-effective method to estimate the mutation risks caused by low-dose-rate radiation (0.08 to 6.86 μGy h^-1) in two widely cultivated tree species of Japan growing in the contaminated area. They used a new bioinformatics pipeline to evaluate de novo mutations (DNMs), or genetic changes/mutations that were not present earlier or inherited, in the germline of the gymnosperm Japanese cedar and the angiosperm flowering cherry.

The study, led by Dr. Saneyoshi Ueno from the Forestry and Forest Products Research Institute, was recently published in the journal Environment International and involved contribution from Dr. Shingo Kaneko from Fukushima University. "People living in the affected areas are worried and need to feel safe in their daily lives," says Dr. Kaneko when asked about the motivation behind their study. "We wanted to clear the air of misinformation regarding the biological consequences of the nuclear power plant accident."

For sampling Japanese cedar, the team first measured the radioactive cesium (¹³⁷Cs) levels of the cone-bearing branches. The cones were then used to collect the seeds, which were germinated, and the remaining megagametophytes were used for DNA extraction.