Based on the lastest science, Health Canada has updated the drinking water guideline to reduce the maximum acceptable concentration of lead from 0.01 mg/L, which was set in 1992, to 0.005 mg/L. The guideline was updated in collaboration with the provinces, territories and other federal departments.
Lead levels in Canadians have fallen dramatically over the past 30 years because of strong actions taken by the Government of Canada to reduce exposure to lead, including limitations on lead use in:
- smelters, steel mills, refineries, and mining operations;
- paints, ceramics, glassware, kettles, corded window coverings, cosmetic products, and pharmaceuticals; and,
- a range of other natural health and consumer products, especially those intended for children.
While lead levels have been significantly reduced, the metal can still be found in the world around us. Lead is usually found in drinking water after leaching from distribution and plumbing system parts. It was historically used in service lines (i.e., pipes connecting a home or business to a street’s water main) and in plumbing fittings and solders.
Until 1975, lead was an acceptable material in pipes based on the National Plumbing Code of Canada, so it is more likely to be found in older homes and neighbourhoods. Since lead was regularly used in these plumbing system parts for many years, drinking water systems in Canada may still have some of these lead components in place today. As such, it is expected to take time before all jurisdictions are able to meet the new guideline for the maximum concentration of lead in drinking water.
All jurisdictions in Canada agree on the need to reduce exposure to lead. Health Canada will continue support provinces, territories and other federal departments in implementing the new guideline. Health Canada will also work with provinces, territories and other federal departments, including Indigenous Services Canada, to provide accurate and relevant information to municipalities and Canadians concerned about the health effects of lead levels in drinking water.
The Canadian Water and Wastewater Association (CWWA) has prepared a fact sheet and other resources for water professionals, which are available here.