Trisiloxane SNAc, terpene assessments, and melamine

Summary#

This Canada Gazette issue publishes several Environment notices that affect how some chemicals are assessed and used in Canada. Key items include a Significant New Activity Notice No. 21912 for trisiloxane, 3-ethyl-1,1,1,3,5,5,5-heptamethyl- (CAS 17861-60-8), draft assessment conclusions for a group of 14 terpene and terpenoid substances (proposing that 12 of them meet criteria under the Canadian Environmental Protection Act, 1999), and supplemental material and updated risk management scope for melamine. The public can comment from January 25, 2025 to March 26, 2025.

What it does#

• Significant New Activity (SNAc) for trisiloxane (CAS 17861-60-8):

  • Declares certain new uses of the substance in cosmetics to be "significant new activities" that must be reported to the government before they begin.
  • Exemptions (allowed without notification) include:
    • hair dye with the substance at 5% by weight or less,
    • rinse-off cosmetics with the substance at 10% by weight or less,
    • foundation makeup, facial makeup remover, hair gel, or lipstick with the substance at 1% by weight or less.
  • For now there is a transitional allowance: between publication and January 24, 2026, the notice only applies if the planned use or sale involves more than 100 kg of the substance.
  • Anyone proposing a covered use must submit a notification at least 90 days before starting and provide specified toxicity and use information (including certain OECD-style lab studies).
  • Uses for research and development, site-limited intermediates, or export-only manufacture are excluded.

• Draft assessment of 14 terpene and terpenoid substances:

  • The government proposes that 12 substances (including cade oil, jonquil oil, Verbena officinalis extract, Ginkgo biloba extract, myrrh oil, cork tree extract, sage oil, wormwood oil, isobornyl cyclohexanol (IBCH), sandal cyclohexanol, bornyl cyclohexanol (BCH), and sandela) meet one or more criteria under section 64 of the Canadian Environmental Protection Act, 1999 (meaning they may be harmful to human health).
  • It proposes no further action for norlimbanol and amberlyn.
  • The notice flags human-health concerns from consumer uses such as cosmetics, natural health products, air fresheners, DIY essential-oil use, and some cleaning products.
  • A risk management scope document has been released to start discussions about how to respond.

• Supplemental material on melamine:

  • An updated human-health risk characterization for melamine (CAS 108-78-1) has been released; the ministers’ proposed conclusion that melamine meets CEPA criteria remains unchanged.
  • The update highlights concerns such as carcinogenicity and effects on the urinary system and reproduction, and identifies consumer sources of exposure (for example, melaware/bambooware, foam-containing products like mattresses and child restraints, paints, sealants, and cooktop cleaners).
  • An updated risk management scope is also published.

• Public participation:

  • Written comments are invited on the draft assessments and supplemental materials during the public comment window: January 25, 2025 to March 26, 2025.

Who's affected#

• Cosmetic manufacturers, formulators, importers and retailers that use or sell products containing the named substances — especially those using trisiloxane (CAS 17861-60-8) in products that exceed the listed concentration or quantity thresholds.
• Companies that make, import, or sell the 14 terpenes and terpenoid substances, or products that contain them (cosmetics, fragrances, natural health products, cleaning products, air fresheners, essential oils, DIY blends).
• Manufacturers, importers, and sellers of products containing melamine (for example, tableware/“melaware”, mattresses, upholstered furniture, child restraint systems, paints, and cleaners).
• Researchers, public-health groups, industry associations, and members of the public who want to comment on the assessments or provide data during the public comment period.
• Users at higher risk (for example, infants and young children) were specifically considered in the assessments and may be most affected by any future restrictions.

Why it matters#

• Companies planning to start or expand uses of trisiloxane in cosmetics may need to pause and submit technical data and wait 90 days for assessment before proceeding. That can delay product launches or imports.
• If the government finalizes the proposed conclusions for the terpene group, regulatory actions or restrictions could follow. That may change what ingredients are allowed in some cosmetics, personal-care items, fragrances, or DIY products.
• The melamine update reinforces concerns about common consumer items (tableware, foam products, some paints and cleaners). Future rules or labelling changes could affect manufacturers and consumers, and may target reducing exposure for infants and children.
• The public comment window (January 25, 2025 to March 26, 2025) is a chance for industry, scientists, and citizens to submit data or viewpoints that could influence final decisions.