On October 25, 2025, Environment and Climate Change Canada (ECCC) and Health Canada announced a 60-day public consultation in Part I of the Canada Gazette on the proposal to add “manganese and its compounds” to Part 2 of Schedule 1 under the Canadian Environmental Protection Act, 1999 (CEPA 1999). The proposal indicates the government’s intent to classify these substances as “toxic” and introduce corresponding national risk management measures.
Background
Manganese is Canada’s third most widely used metallic additive, with annual imports of roughly 14,000 metric tons. It is primarily used in steel manufacturing, batteries, fertilizers, cosmetics, and fuel additives.
Following a scientific review, the government published a Draft Assessment and a Risk Management Scope on October 25, 2025. The assessment concluded that manganese and its compounds may enter the environment in quantities or concentrations that could cause immediate or long-term harm to ecosystems and pose a risk to human health, meeting the criteria for toxicity under sections 64(a) and 64(c) of CEPA.
This finding supports the proposed addition of manganese and its compounds to Part 2 of Schedule 1, paving the way for upcoming regulatory and risk management actions.
List of manganese substances identified as priorities for assessment
| CAS RN | DSL or R-ICL na | Common name |
| 1313-13-9 | Manganese oxide | Manganese dioxide |
| 1335-36-0 | 1,2,3-Propanetriol, mono(dihydrogen phosphate), manganese salt | Manganese glycerophosphate |
| 1344-43-0 | Manganese oxide | Manganese oxide |
| 7439-96-5 | Manganese | Elemental manganese |
| 10101-66-3 | Diphosphoric acid, ammonium manganese (3+) salt (1:1:1) | Ammonium manganese pyrophosphate / Manganese violet |
| 12108-13-3 | Manganese, tricarbonyl[(1,2,3,4,5-<C)-1-methyl-2,4-cyclopentadien-1-yl]- | Methylcyclopentadienyl manganese tricarbonyl (MMT) |
| 18820-29-6 | Manganese sulfide | Manganese sulfide |
| 29193-02-0 | L-Proline, 5-oxo-, manganese salt (1:?) | Manganese pyroglutamate |
| 35355-77-2 | C.I. Pigment Red 63:2 | C.I. Pigment Red 63:2 |
| 68551-42-8 | Fatty acids, C6-19-branched, manganese salts | Manganous (C6-C19) branched alkanoate |
|
105883-50-9 |
Manganese, bis[N-(acetyl-.k.O)-L-methioninato-.k.O]- | Manganese acetyl methionate |
Public Consultation
The public comment period is open until December 24, 2025. Individuals and organizations are invited to submit feedback on the “Proposed Listing Conclusion” and “Risk Management Scope” through the following channels
· Email: substances@ec.gc.ca
· Online: via Environment and Climate Change Canada’s Single Window System
