Scientific Criticism in the Dispute over the Risk of Radiation Exposure

This study examines the role of scientific criticism in the dispute over health effects of exposure to low-level radiation, focusing on the situation in Japan after the Fukushima Daiichi nuclear disaster. In radiation-related fields, it has usually been difficult for environmental movements to establish and utilize a network of scientists who provide a scientific basis for the movement, because of the strong connection between government officials promoting nuclear energy and scientists in these fields. Considering these difficulties, I will examine what enables scientists to maintain an objective distance and conduct academic research with possible critical implications for the existing policy.

On the basis of a document analysis of historical materials and in-depth interviews with the people involved, we found a remarkable difference between scientific fields regarding research resources available for outsider scientists. In the field of dosimetry, many citizen groups measured doses of radiation using their own dosimeter, which enabled them to urge the government to adjust their policy of decontamination. However, in epidemiology, it is difficult for critical scientists to conduct large-scale surveys; therefore, they have concentrated on assessing and criticizing Fukushima Prefecture’s “Health Management Survey.”

We also found a complex relationship between academic research diversity and political mechanisms for constructing a unified view. Occasionally, articles in international journals express different views; for example, one uncovers the possibility of health effects caused by very low-level radiation and another denies it. Even though the academic discussion has not yet been completed, the International Commission on Radiological Protection (ICRP) has taken the position of creating a systematic regulation; consequently, the diversity of academic research has diminished. To maintain diversity in the circulation of scientific knowledge, we need alternative ways to organize critical scientists and the results of their research.