Cyanides

These substances were identified for action under the Chemicals Management Plan (CMP). The ecological portion of the screening assessment used a moiety-based approach that focused on free cyanide [hydrogen cyanide (HCN) and the cyanide anion (CN-)] and precursors of free cyanide. As such, the ecological moiety conclusion includes, but is not limited to, the 10 substances identified in the table below; however, the human health conclusion is limited to those 10 substances.

• Summary of publications
• Timelines
• Information gathering
  • Section 71 CMP 2023

Summary of publications

Substance group	CAS RN (cyanides that met categorization criteria)	Common name	DSL name	Proposed order and RIAS	Public comments on the draft screening assessment	Final screening assessment	Proposed risk management approach	Conclusion on section 64 criteria	Follow-up activities
Cyanides	74-90-8	Hydrogen cyanide	Hydrocyanic acid	HTML	HTML	HTML	HTML	Meets one or more of the criteria	Refer to proposed risk management approach
	143-33-9	Sodium cyanide	Sodium cyanide
	506-61-6	Potassium dicyanoargentate	Argentate(1-), bis(cyano-C)-, potassium
	13601-19-9	Tetrasodium ferrocyanide (yellow prussiate of soda)	Ferrate(4-), hexakis(cyano-C)-, tetrasodium, (OC-6-11)
	13746-66-2	Tripotassium ferricyanide	Ferrate(3-), hexakis(cyano-C)-, tripotassium, (OC-6-11)-
	13943-58-3	Tetrapotassium ferrocyanide (yellow prussiate of potash)	Ferrate(4-), hexakis(cyano-C)-, tetrapotassium, (OC-6-11)-
	13967-50-5	Potassium dicyanoaurate	Aurate(1-), bis(cyano-C)-, potassium
	14038-43-8	Ferric ferrocyanide (Prussian blue, insoluble)	Ferrate(4-), hexakis(cyano-C)-, iron(3+) (3:4), (OC-6-11)-
	25869-00-5	Ferric ammonium ferrocyanide	Ferrate(4-), hexakis(cyano-C)-, ammonium iron(3+) (1:1:1),(OC-6-11)-
	25869-98-1	Potassium ferric ferrocyanide (Prussian blue, soluble or Turnbull's blue)	Ferrate(4-), hexakis(cyano-C)-, iron(3+) potassium (1:1:1), (OC-6-11)-

Timelines

Date	Activity
June 24, 2023	Publication in Canada Gazette, Part I, of a notice under section 71 of the Canadian Environmental Protection Act, 1999 (CEPA 1999).
March 18, 2023	Publication in the Canada Gazette, Part I, Vol. 157, No. 11 and start of a 60-day public comment period on a proposed order adding free cyanide, cyanide salts and cyanide complexes to Schedule 1 to the Canadian Environmental Protection Act, 1999.
February 25, 2023	Publication of the final screening assessment. The proposed risk management approach was also published for a 60-day public comment period. The related notice was published in the Canada Gazette, Part I, Vol. 157, No. 8.
February 10, 2018	Publication and start of 60-day public comment period on the draft screening assessment and the risk management scope. The related notice was published in the Canada Gazette, Part I: Vol. 152, No. 6.

Information gathering

Section 71 CMP 2023

In June 2023, a notice was published in the Canada Gazette, Part I: Vol. 157, No. 25 – June 24, 2023 under section 71 of CEPA 1999. This notice applies to HCN (CAS RN 74-90-8). More information is available on the Information gathering with respect to certain substances under the Chemicals Management Plan web page.