On October 25, 2025, Environment and Climate Change Canada (ECCC) has issued a notice under Section 87(3) of the Canadian Environmental Protection Act, 1999 (CEPA 1999), proposing to remove diisodecyl adipate (DIDA, CAS No. 27178-16-1) from Part 1 of the Domestic Substances List (DSL) and reclassify it under Part 2 as a substance subject to "Significant New Activity" (SNA) regulations.
Background
DIDA is currently listed in Part 1 of the DSL, indicating its historical commercial use in Canada between 1986 and 1996. A recent systematic assessment by Canadian authorities identified potential risks associated with its high-concentration use in certain consumer products, cosmetics, natural health products, and over-the-counter drugs.
Proposed Controls
Under the draft regulations (see Annex), the following activities will be classified as "Significant New Activities" requiring advance notification:
1. Manufacturing DIDA-containing products
- Non-spray lubricants or automotive fluids with DIDA concentrations >84%;
- Spray lubricants with DIDA concentrations >15%;
- Other consumer products, cosmetics, natural health products, or non-prescription drugs with DIDA concentrations ≥0.2%;
- Lip liners with DIDA concentrations >10%.
2. Importing DIDA-containing products
Annual imports exceeding 10 kg with concentrations meeting the above thresholds must also be reported.
3. Exemptions
Activities involving research and development, on-site intermediates, or products solely for export are exempt.
Public Consultation
Stakeholders may submit comments by December 24, 2025, through the following channels:
- Email: substances@ec.gc.ca
- Mail: Regulatory Operations Division, Department of the Environment, Gatineau, QC K1A 0H3
- Online: Environment and Climate Change Canada Single Window System
Implementation
Upon formal listing in DSL Part 2, any proposed SNA-related manufacturing or import activities must submit detailed information to the government 90 days in advance for environmental and human health risk assessments.
Further Information
