Why is lead in water important?

Lead is a heavy metal, and it is known to have adverse effects on human health. Even at low concentrations, lead may have minor effects on the intellectual development of infants, children under 6 years of age and fetuses in exposed pregnant women. The current scientific consensus is that the amount of lead in water should be reduced.

Where does lead come from?

Lead is naturally present in the soil in small quantities and can dissolve in water that comes in contact with these soils. However, those in charge of drinking water plants do very frequent checks, and lead is controlled at the source. The main source of lead contamination in the faucet is therefore piping. The National Plumbing Code allowed the use of lead as a material until 1975, and in welds until 1986. There may also be some in some brass faucets and fittings.

When the water stays in the pipe for a long time, the lead can be solubilized in the water. The amount that passes is often very small, but the threshold of 5µg/L indicates that, for a cup of water, the maximum tolerable lead is 0.00000125g! This corresponds to a dissolution of 0.1 millionth of an inch, or 0.0000000001 inch… it is invisible to the naked eye.

How do I know if my water is contaminated with lead?

A simple laboratory analysis can detect and measure the amount of lead. To find out if the plumbing in the house contains lead, you can simply sample the first portion that comes out of the taps in the morning. Contact us for information on sampling, costs and analysis times.

What if my water is contaminated?

The best way to eliminate the problem is to eliminate the source of the contamination. In some cases, this may mean replacing parts of the plumbing in the home. In other cases, the situation cannot be corrected because the problem comes from the pipes of the municipality.
If the lead comes from a stagnation of water in the pipes, one solution may be to let the water run for about 1 minute before consuming it. It would also be recommended to use only cold water for consumption, as lead is more soluble in hot water.

Cleaning the faucet can help in some cases; Cleaning aerators, cleaning grates and inspecting piping every month to make sure there is no debris.
A water filter can also be a temporary solution. However, this has to be done with caution, as this type of filter must be properly maintained to be effective. It would also be advised to test the water with and without your filter to check its effectiveness, and to check the water periodically to ensure its continuous performance.

As a last resort, if the modifications, measures or appliances do not allow for water that meets lead limits, bottled water may be considered.

Sources:

https://www.canada.ca/fr/sante-canada/services/sante-environnement-milieu-travail/rapports-publications/quen-est-il-du-plomb.html
http://www.environnement.gouv.qc.ca/eau/potable/plomb/
https://ici.radio-canada.ca/nouvelle/1358297/modification-ajustement-rqep-reglement-qualite-eau-potable