Domestic Substances List CAS update

Summary#

Order 2024-66-02-01 Amending the Domestic Substances List updates the list of chemicals maintained by the federal government. It removes CAS number 1646857-41-4 from Part 1 of the Domestic Substances List and adds CAS number 1646857-41-1 instead. The order came into force on February 27, 2024 and was published in the Canada Gazette on March 13, 2024.

What it does#

• Deletes CAS RN 1646857-41-4 from Part 1 of the Domestic Substances List.
• Adds CAS RN 1646857-41-1 to Part 1 of the Domestic Substances List, placing it in numerical order.
• The order was signed by Steven Guilbeault on February 22, 2024, and it became effective on the day it was registered (February 27, 2024).

Who's affected#

• Businesses that make, import or use the substance identified by these CAS numbers.
• Laboratories, environmental consultants and compliance staff who track DSL listings.
• Government staff and stakeholders who monitor or regulate chemicals under the Canadian Environmental Protection Act, 1999.

Note: The Gazette notice lists only the CAS numbers and does not give a chemical name or reason for the change. That makes it unclear exactly which product lines or sectors will be affected.

Why it matters#

• The Domestic Substances List is the official inventory the government uses to track chemicals in Canada. Being on or off the list can affect reporting, testing, and regulatory attention.
• Even small edits like swapping a CAS number can matter for companies that must prove which exact substance they make or import.
• The notice itself is a short administrative change; the document with more explanation (the Regulatory Impact Analysis Statement) is published elsewhere in the Gazette for readers who want more detail.