Annual changes in the Fukushima residents’ views on the safety of water and air environments and their associations with the perception of radiation risks

Fukushima residents' negative views on the safety of water and air environments have been a concern since the Fukushima Dai-ichi Nuclear power plant (FDNPP) accident. The objective of this study was to clarify the factors determining these negative views and their association with radiation risk perception using the opinion poll conducted by Fukushima Prefecture from 2010 to 2015. In a model, in which the objective variables were the views on the safety of water and air environments, and the explanatory variables were the regions constituting Fukushima and the age and sex of the residents, the odds ratio (OR) of the views on the safety of the water and air environments (reference region: the least affected region) was significantly low at 0.11 [95% confidence interval (CI): 0.04-0.28] to 0.18 (0.07-0.46) in the Hamadori region including the evacuation order area, from the accident in 2011 to 2015, with the exception of 2014. In another model, in which the region was excluded from the explanatory variables and radiation risk perception, the distance from the FDNPP and the air dose rate were added to the previous model as an explanatory variable, the views on the safety of the water and air environments were strongly associated with low radiation risk perception (low anxiety) in 2012-2015 [OR: 7.73 (5.25-11.4) to 10.3 (6.71-15.8)], distance from FDNPP, and age, but not with air dose rate. This result suggests that the radiation risk perception, distance from FDNPP, and age were factors determining people's views on the safety of the water and air environment.