Japan: MHLW adds 29 entries to the list of chemicals that cause skin irritation

On 18 July 2025, The Ministry of Health, Labour, and Welfare (MHLW) in Japan released a list of substances that have been found to irritate skin or absorb through the skin. The list was made public on the Japan's Workplace Safety Site by MHLW. In addition with this update, MHLW also eliminated three entries from the list.

Regulatory Background

The Industrial Safety and Health Regulations, which went into effect on April 1, 2024, stipulate in Article 594-2 that using impermeable protective equipment is required when handling specific substances.  By ensuring that employees are sufficiently shielded from direct exposure to dangerous chemicals, this rule lowers the possibility of skin irritation and other health issues.

Obligations for chemical handlers

Employers and employees who handle chemical preparations above the designated cut-off value are required to wear impermeable protective equipment, such as gloves and protective clothes, to shield their skin from potentially harmful compounds.

Earlier Update in February 2025

Previously on 26 February 2025, MHLW revised the list of chemicals causing skin irritation. More information can be found here.

Key Findings from the Updated Skin Irritating List

Data obtained as of July 14, 2025, is included in 1236 entries of compounds in the updated list. The following details are included in the list:

• CAS number
• Name in accordance with the Industrial Safety & Health Act
• Chemical name in accordance with Japan's GHS classification
• Additional provisions
• % Cut-off value
• Effective date