Japan Publishes Notice Designating Three Priority Assessment Chemical Substances Under the Chemical Substances Control Law 
On April 1, 2025, Japan issued a public notice designating three substances as priority assessment chemical substances under the Chemical Substances Control Law. The newly designated substances are:
– Copper(I) thiocyanate
– N-decyl-N-ethyl-N-methyl-1-decanaminium salt
– α-Hydro-ω-{[(9Z)-octadec-9-enoyl]oxy}poly(oxyethane-1,2-diyl) (with a repeat unit count of one or more)
What Are Priority Assessment Chemical Substances?
Priority assessment chemical substances are those deemed to require urgent risk evaluation for their potential hazards. They are designated by Japan’s Minister of Health, Labor and Welfare, Minister of Economy, Trade and Industry, and Minister of the Environment. A chemical substance is classified as a priority assessment substance if it meets all the following criteria:
1. Potential long-term toxicity to humans or environmental organisms cannot be ruled out.
2. Manufacturing and import conditions suggest the substance remains in the environment in significant quantities or is likely to accumulate.
3. The potential for environmental pollution caused by the substance poses a risk to human health or the survival and growth of environmental organisms.
Requirements for Businesses Handling Priority Assessment Chemical Substances
Businesses handling priority assessment chemical substances must comply with the following obligations:
– Reporting:
Manufacturers or importers handling one ton or more of a designated priority assessment chemical substance must submit an annual report to the Minister of Economy, Trade, and Industry. The report must detail the previous year’s production volume by prefecture or import volume by country/region, along with usage information.
Reporting is not required if the substance is used exclusively for testing and research purposes or if the annual volume is less than one ton.
– Information Disclosure:
Businesses that use or handle priority assessment chemical substances must provide relevant information, such as the chemical’s name, when transferring or supplying the substance to other entities.
Related Links
Official Gazette: Notice Designating Priority Assessment Chemical Substances
https://www.kanpo.go.jp/20250401/20250401h01435/20250401h014350007f.html
List of Priority Assessment Chemical Substances (as of April 1, 2025)
https://www.meti.go.jp/policy/chemical_management/kasinhou/files/yusen/yusen_ichiran.pdf
