Chlorhexidine and its salts

Chlorhexidine and its salts were identified as priorities for assessment through the categorization of substances on the Domestic Substances List (DSL), or were considered a priority based on other concerns. The screening assessment focused on chlorhexidine and its salts. It includes, but is not limited to, the 4 substances identified in the table below.

• Summary of publications
• Timelines
• Proposed environmental performance agreement (EPA)
• Adding substances to Schedule 1
• Adding substance to the National Pollutant Release Inventory (NPRI)
• Final screening assessment and proposed risk management approach
• Background

Summary of publications

Proposed environmental performance agreement (EPA)

In February 2022, the proposed Environmental Performance Agreement for the Formulation of Chlorhexidine Products was published for a 60-day public comment period. The proposed agreement requires the participating facilities to minimize releases of chlorhexidine to levels that are protective of the aquatic environment and report on the implementation of best management practices. The objective of the agreement is to help reduce the concentration of chlorhexidine in wastewater released from industrial facilities that formulate chlorhexidine-based products.

Comments received on the proposed agreement will be considered in the development of the final agreement. A code of practice containing best practices to minimize the release of chemical substances into the environment, applicable to the broader chemicals sector, is also under development.

Adding substances to Schedule 1

Chlorhexidine and its salts are proposed to be added to Schedule 1.

• Proposed order adding chlorhexidine and its salts: Canada Gazette, Part I: vol. 155, No. 10 – March 6, 2021.

Adding substances to the National Pollutant Release Inventory (NPRI)

In March 2021, the proposal to add chlorhexidine and its salts to the NPRI was published for a 70-day public consultation period. The purpose of the consultation was to seek input from the NPRI multi-stakeholder working group, as well as members of the public on whether to add chlorhexidine (and its salts) to the list of substances that must be reported to the NPRI, as well as the proposed reporting threshold of 100 kg of chlorhexidine and its salts manufactured, processed or otherwise used above 1% concentration.

The decision was made to add chlorhexidine (and its salts) to the NPRI, and the requirement was included in the 2022 to 2024 notice for the NPRI, published in the Canada Gazette, Part I, Vol. 156, No. 7 – February 12, 2022. A final report, including a summary of comments received during consultation and the Government's responses, will be available by March 2022.

Final screening assessment and risk management approach

In June 2019, the Final Screening Assessment for Chlorhexidine and its Salts was released and the related notice was published in the Canada Gazette, Part I: Vol, 153, No. 26 – June 29, 2019.

The final screening assessment concluded that chlorhexidine and its salts meet one or more of the criteria set out in section 64 of CEPA 1999; therefore, the Government is proposing to add these substances to Schedule 1 to the Act. A proposed risk management approach was also released on this date for a 60-day public comment period.

Comments and the Government's response relating to general themes on the proposed risk management approach are provided in the summary of public comments received on the proposed Risk Management Approach for Chlorhexidine and its Salts.

In August 2017, the updated Draft Screening Assessment for Chlorhexidine and its Salts was released and the related notice was published in the Canada Gazette, Part I: Vol. 151, No. 33 – August 19, 2017. A risk management scope was also released in conjunction with this publication. There was a 60-day public comment period associated with these publications.

Comments and the Government's response relating to general themes on the draft screening assessment and the risk management scope are provided in the summary of public comments received on the Draft Screening Assessment for Chlorhexidine and its Salts

Background

A draft screening assessment for 1 of these substances, chlorhexidine diacetate, was published in July 2013 as part of Batch 12 of the earlier Challenge Initiative of the Chemicals Management Plan (then referred to as chlorhexidine acetate). At that time, this substance was proposed not to be harmful to human health, but harmful to the environment.

After publication of the July 2013 draft screening assessment (available upon request), significant new information became available regarding other potential sources of exposure to the chlorhexidine moiety. This includes information on quantities and commercial use of chlorhexidine (CAS RN 55-56-1) and chlorhexidine digluconate (CAS RN 18472-51-0) received under phase 2 of the DSL inventory update. Chlorhexidine and its salts may also be present in products sold in Canada. As chlorhexidine is the moiety of toxicological concern resulting from the separation in water of chlorhexidine salts, there was a gap in the evaluation of potential impacts on the environment and human health with respect to characterizing combined exposure from all potential sources of chlorhexidine.

Therefore, to consider exposure from all potential sources of the chlorhexidine moiety, chlorhexidine diacetate was removed from Batch 12 and was included in a screening assessment of a broader group of substances, called chlorhexidine and its salts.