Health Canada launches automated chemical prioritization

Summary#

Health Canada published a science approach document that explains a new automated method (the Health Canada Automated Workflow for Prioritization, HAWPr) for screening chemicals. The method and preliminary results for about 25,200 substances on the Domestic Substances List may be used to prioritize chemicals under the Canadian Environmental Protection Act, 1999. The notice was published August 17, 2024 and there is a public comment window of 60 days.

What it does#

• Describes the HAWPr tool, an automated workflow that:
  • gathers chemical data from many sources;
  • fills data gaps using predictive models;
  • evaluates evidence and gives confidence scores; and
  • combines hazard and exposure information to rank substances for follow-up.
• Presents preliminary results for about 25,200 substances on the Domestic Substances List and a supporting document.
• Explains that the approach may be used for future prioritization and assessment work under section 68 of the Canadian Environmental Protection Act, 1999.
• Notes the tool can access over 1,000,000 records from curated toxicity and exposure datasets to inform decisions.
• Opens a public consultation: people and organizations can send comments within 60 days of publication. Commenters may ask that information they provide be treated as confidential.

Who's affected#

• Companies that make, import, sell or use chemicals or products that contain chemicals on the Domestic Substances List (manufacturers, importers, distributors).
• Researchers, labs and consultants who produce chemical data or predictive models.
• Public-health and environmental groups that track chemical risks.
• Consumers and communities concerned about potential exposure to chemicals — decisions made with this tool could lead to future assessments or controls on products they use.
• It is not yet clear which specific substances will be singled out for formal assessment; the notice gives a high-level approach and preliminary results only.

Why it matters#

• This is a step toward faster, more consistent screening of large numbers of chemicals. That could speed up which substances get formal health assessments.
• If the tool flags a substance as a potential concern, it could lead to testing, restrictions, label changes, or other government actions that affect industries and consumers.
• The process claims to use large datasets and automated methods to increase transparency and reproducibility — but the tool has limits and uncertainties. The public comment period is an opportunity to raise concerns or provide additional data.