Lead in drinking water mainly comes from the dissolution of lead in pipes, especially connection pipes (service lines) between some houses and the municipal distribution system. Lead service lines were installed in single-family homes and apartment buildings with fewer than 8 dwellings, especially between 1940 and 1955 and even into the ’70s. Welding in the internal plumbing of buildings can also be a source of lead in water.
In Québec, concentration of lead in drinking water may not exceed 0.010 mg/L. Drinking water distribution system officials, including those of municipalities, are responsible for ensuring that this standard is applied.
In general, exposure to lead from drinking water is low and doesn’t cause health problems in adults. Children under 6, including fetuses, are more sensitive to the effects of lead. The effects of exposure to lead over a period of many years are mainly neurobehavioural in nature, such as a decrease in learning ability.
Boiling water is useless because lead does not evaporate. In fact, boiling water may increase the concentration of lead in the water.
For more information on how to reduce lead in drinking water, read Lead in Drinking Water (in French) on the MDDELCC website.
Last update: November 25, 2016 11:19 AM
The information on this website by no means replaces the advice of a health professional. If you have questions regarding your health, contact Info-Santé 811 or see a health professional.