Updated Drinking Water Guidelines for Iron & PFAS
Health Canada, in collaboration with provincial and territorial governments, established a drinking water objective and updated its drinking water guidelines for per- and polyfluoroalkyl substances (PFAS), introducing a new interim objective to address these substances collectively.
Key Changes
PFAS:
- Unified Limit: A single objective of 30 nanograms per litre (ng/L) has been established for the combined concentration of 25 specific PFAS in drinking water. This replaces the previous individual guidelines for perfluorooctane sulfonate (PFOS), perfluorooctanoic acid (PFOA), and screening values for nine other PFAS.
- Precautionary Approach: Given the limited toxicological data for many PFAS and their potential cumulative health effects, Health Canada recommends maintaining PFAS levels in drinking water “as low as reasonably achievable” (ALARA).
- Analytical Methods: The objective is based on concentrations achievable using current analytical methods and treatment technologies, such as granular activated carbon, anion exchange, and reverse osmosis.
- Interim Measure: This objective serves as interim guidance while Health Canada continues to develop comprehensive, health-based guidelines for PFAS in drinking water, a process expected to take several years.
For more detailed information, you can refer to Health Canada’s official document on the Objective for Canadian drinking water quality per- and polyfluoroalkyl substances.
Iron:
Guidelines for Iron in Drinking Water
Health Canada has established an aesthetic objective (AO) for total iron in drinking water at ≤ 0.1 mg/L (100 µg/L). The document is part of Health Canada’s commitment to improving public health in Canada.
Comprehensive Water Safety Management Strategies
- Water treatment systems must implement a risk management water safety plan to ensure safe drinking water from source to tap.
- Control strategies for minimizing iron include managing source water concentrations and optimizing treatment processes to reduce iron inputs.
- Regular monitoring of source water is recommended, with groundwater sampled every 6 months and surface water sampled four times a year.
- Treatment systems should frequently monitor raw and treated water to ensure iron concentrations remain below the acceptable objective (AO).
- Distribution systems should conduct monitoring at various locations to maintain iron concentrations below the AO, especially during discolouration events.
- Event-based monitoring is necessary after hydraulic disturbances or changes in water chemistry to detect potential iron releases.
- Homeowners with private wells should test both incoming and treated water to ensure their treatment devices are functioning properly.
This link will provide you with further information https://www.canada.ca/en/health-canada/services/publications/healthy-living/guidelines-canadian-drinking-water-quality-guideline-technical-document-iron.html