The results of the questionnaire survey of factories subject to the Pollutant Release and Transfer Register (PRTR) system showed that approximately 20% of the factories undertake risk communication by way of factory tours and briefing sessions. There are factories that raise topics and provide information of interest to the public other than chemical management, and actively incorporate the opinions of the public into their risk management. For a problem, the factories that replied to explain the information of released and transferred amounts of chemical substances for community inhabitants in risk communications were only approximately around 3%. In addition, detail information of risk of the chemical substances were not able to confirm in the explanation of risk communications.

When a hydrogen fueling infrastructure such as hydrogen fueling station is introduced to the public, risk assessment in a transparent way and its public announcement will be required. We surveyed the published documents on risk assessment and risk control measures on a hydrogen refueling station in EU, US and Japan and discussed how they gained public acceptance. At first, a risk acceptance criteria was proposed by European Integrated Hydrogen Project in 2003. In the cases of EU and US, safety distance to satisfy the criteria has been decided after (semi-) quantitative risk assessment. On the other hand, risk assessment in Japan did not emphasize the risk acceptance criteria although the risk was appropriately assessed including precise assessment of the mitigation measures. This might be why risk communication to the public faced difficulty in Japan. The quantitative risk assessment in the U.S. has versatility and it will be applicable to Japanese case.

In developed countries with water supply and sewerage systems, risk of waterborne infectious diseases caused by pathogenic bacteria has been controlled at a certain level employing the water quality standards using fecal indicator bacteria. However, behavior of viruses and protozoa in water treatment processes or environmental water is different from those of indicator bacteria, and a quantitative microbial risk assessment (QMRA) approach for the management of risk from specific pathogenic microorganisms has been used in the U.S., etc. In this review article, we overview the waterborne microbial risk studies on the leading edge with pointing out some critical issues in this field. The topics include environmental survey on microbial contamination, risk assessment and modeling, risk management, and risk communication.