Japan Seeks Comments on New CSCL Class I Substances

By Yuko Howell, Regulatory Affairs Lead, Supply Chain Team, UL Solutions

On March 20, 2026, Japan’s Ministry of Health, Labour and Welfare (MHLW), Ministry of Economy, Trade and Industry (METI), and Ministry of the Environment (MOE) opened a public comment period on a proposed amendment to the Chemical Substances Control Law (CSCL). The draft amendment seeks to newly designate Long chain perfluoroalkane acids (LC PFCAs), LC PFCA related substances, Chlorpyrifos, and Medium chain chlorinated paraffins (MCCPs) as Class I Specified Chemical Substances, following their decision for global elimination at the 12th Meeting of the Conference of the Parties (COP 12) to the Stockholm Convention.

Targeted Chemical Groups

The proposed CSCL amendment would add the following to the Class I list:

• Long chain perfluoroalkane acids (LC PFCAs, C9–21) and their salts
• LC PFCA related substances, defined as compounds containing perfluoroalkyl groups (C8–20) that degrade into LC PFCAs through natural processes
• Chlorpyrifos (O,O Diethyl O (3,5,6 trichloro 2 pyridyl) phosphorothioate)
• Medium chain chlorinated paraffins (MCCPs), defined as straight chain chlorinated alkanes (C14–17) with chlorine content ≥45% by weight

These substances fall under the CSCL definition of Class I Specified Chemical Substances, meaning they are considered difficult to biodegrade, highly bioaccumulative, and pose risks of long‑term toxicity to humans or higher trophic‑level organisms.

Proposed measures under CSCL

Once designated as Class I Specified Chemical Substances, the following controls will apply:

• Prohibition on manufacture and import, except in limited cases requiring government authorization
• Import bans on products containing the substances
• Technical standards and labeling obligations for certain products containing LC PFCAs and LC PFCA related substances
• No essential use exemptions included in the proposal

These measures align with Japan’s obligations under the Stockholm Convention.

Public comment period

Japan is currently inviting public comments on the proposal:

Public comment period: March 20, 2026 – April 18, 2026 (must arrive by deadline)

Comments may be submitted via the official public comment portal. (See References)

Next steps and implementation timeline

After the public consultation closes, the government plans to:

• Review submitted comments
• Finalize and promulgate the amended Enforcement Order around May 2026
• Implement full enforcement around November 2026

This timeline reflects the implementation schedule outlined in the CSCL amendment notice.

References

• Draft Measures Concerning Chlorpyrifos, MCCPs, and LC-PFCAs under CSCL (Japanese only)
• Public Comment Submission Portal (Japanese only)