Systemization of the Establishment of Standards and Future Prospects: Toward the Establishment of Standards in Nonstationary States.

Although public interest on safety standards is increasing, the evidence and protocols associated with the standards are not known well to the public and even experts. Discussing the evidence of standards is essential for risk communication, and interdisciplinary and systematical understanding on how to establish standards are also beneficial for considering the set-up of new standards. In this article, on the basis of examples in environmental science, industrial health and safety, and radiological protection, I overview and systemize the establishment of the standards from the perspectives of three principles of risk management: 1) "zero-risk-like" standards, 2) "acceptable-risk-based" standards, and 3) "cost-balanced" standards. In this view, I point out the differences in uncertainty factors or acceptable-risk levels among individual standards and demonstrate the role of the "as low as reasonably achievable (ALARA)" concept. Then, on the basis of the problem on lack of environmental standards in nonstationary states such as disasters, I summarize elements necessary for establishing the standards. As perspectives for further study, I suggest the needs for risk assessment of chemicals having a threshold, full considerations of risk trade-offs and ethical aspects, and applications of processes to the establishment of standards through stakeholder consensus.