The Ministry of Health, Labour and Welfare (MHLW) of Japan recently announced that after testing 643 notified chemical substances, 17 have been confirmed to possess high mutagenic properties. These chemicals are considered capable of causing permanent changes to the DNA sequence. Details of the testing results and the chemicals have been published in the official gazette.
According to the Industrial Safety and Health Act (ISHA), as of December 7, 2023, a total of 1,346 substances have been identified as highly mutagenic. In response, the MHLW requires all businesses handling these chemicals to follow the Guidelines for Preventing Health Risks Caused by Highly Mutagenic Chemicals and to implement the following measures to protect workers' health and safety:
- Manage the work environment, including changing usage conditions, improving workflows, equipment encapsulation, and installing local exhaust ventilation.
- Choose work positions, postures, or methods that prevent exposure to highly mutagenic chemicals.
- Use personal protective equipment such as respiratory protection and protective gloves.
- Reduce the time of exposure to highly mutagenic chemicals.
- Measure, monitor, and record the indoor work environment and employee activities, and retain results of environmental measurements and evaluations for 30 years.
- Provide occupational health education to workers who handle or are about to handle highly mutagenic chemicals. The education should cover the properties and hazards of the substances, potential health risks, prevention methods, emergency measures, and maintenance and inspection methods for related equipment.
Furthermore, if measures such as installation of exposure-reducing equipment have been implemented, businesses must also ensure:
- Normal operation of local exhaust ventilation and similar devices during work.
- Regular maintenance and inspection of local exhaust devices.
- Preparation of an adequate quantity of protective equipment for workers, maintaining its effectiveness and cleanliness. When using supplied-air respirators, measures should be taken to ensure workers do not inhale harmful air.
The MHLW also reminds all companies that produce and handle these substances to label the containers or packaging according to industrial safety and health regulations and to notify users through Safety Data Sheets (SDS) and other means.
This measure by the MHLW marks a further strengthening of chemical safety management, aimed at reducing workers' exposure to hazardous chemicals and ensuring public health and safety.
Detailed information about the names, structural formulas, properties, and usage examples of the 17 chemicals can be accessed through the official website of the MHLW:
