MHLW Call for Opinions on Draft Amendment to Technical Guidelines for Chemical Substance Concentration Standards

"On April 23, 2025, the Ministry of Health, Labor and Welfare (MHLW) released a Call for Opinions on the draft amendment to the Technical Guidelines for the Application of Concentration Standards for the Prevention of Health Hazards Caused by Chemical Substances. This amendment is in response to the Industrial Safety and Health Act (Act No. 57 of 1972) and aims to update existing concentration standards for chemical substances in workplaces to better protect worker health. The comment period is open until May 22, 2025. Key details of the proposed amendments include: 1.Newly Established Standards: 78 substances will have newly established concentration standards. These substances will also have their measurement methods added to Appendix 1 of the guidelines. 2.Substances with No Established Standards: For 2 substances, 2-nitropropane and bromoethylene, concentration standards cannot be established due to their clear carcinogenicity. These substances will be listed in Appendix 2 with a note stating that no concentration standards can be set. 3.Changes to Butyl Acetate: Secondary butyl acetate will be added to the existing butyl acetate listing in Schedule 1 and Schedule 2. 4.Removal of Triphenyl Phosphate: Triphenyl phosphate will be removed from Schedule 1 and Schedule 2, following its exclusion from risk assessment targets in the Cabinet Order partially amending the Enforcement Order of the Industrial Safety and Health Act and the Ministerial Order of 2025. -Following are the some of substances name which are effective on October 1, 2025: Ethyl acrylate; Normal butyl acrylate (Omitted); 3-amino-1H-1,2,4 -Triazole (also known as amitriazole); Alpha-Methylstyrene; Isoprene etc. -Following are the some of substances name which are effective on October 1, 2026: 2-Ethylhexyl acrylate Solid collection method; 2-Hydroxypropyl acrylate; 2-amino-2-methyl-1-Propanol; Isooctanol; N-isopropylaminophospho O-ethyl-O-(3-methylphenyl); 1-ethoxy-2-propanoate etc. -The deletion of triphenyl phosphate from the Schedule will take effect on April 1, 2027