Lead and Drinking Water

Lead is a metal commonly found in the environment, both naturally and as a result of human activities.¹ Everyone is exposed to trace amounts of lead through air, soil, dust, food, drinking water and various consumer products,¹ such as batteries, lead-painted wood, paint and unregulated cosmetics.

Ontario’s Drinking Water Quality Standards currently allow up to 10 micrograms per litre (parts per billion) of lead in drinking water.² The Middlesex-London Health Unit works with municipalities to ensure that water throughout our jurisdiction consistently meets this standard.

What are the health effects of lead?

Young children are particularly vulnerable to the toxic effects of lead and can suffer profound and permanent adverse health impacts, particularly on the development of the brain and nervous system.³ Lead also causes long-term harm in adults, including increased risk of high blood pressure and kidney damage.³ Exposure of pregnant women to high levels of lead can cause miscarriage, stillbirth, premature birth and low birth weight.³

How do I know if I have lead in my water?

In Canada, the concentrations of lead in drinking water supplies do not represent a hazard to Canadians as concentrations are normally below the maximum acceptable concentration.¹ However, water can pick up lead if it flows through a lead water service, particularly pipes that bring water into houses and businesses. Since 1990, the Canadian National Plumbing Code has restricted the use of lead solder in new plumbing and in repairs to plumbing for drinking water supplies.¹

To determine if you have lead services lines in your area, you can check with your municipality or water utility. If you live in the City of London and have questions about lead testing please contact the City of London at:

• 519-661-2489 ext. 5541, or
• email leadtesting@london.ca

What should households do?

If you know or suspect you have a lead service line or fittings with lead solder, the best way to reduce your lead exposure is to replace all lead bearing materials and make sure that any solder in your plumbing is lead free. A licensed plumber would be able to assist you in the assessment of your interior piping. If you obtain drinking water from a private well, it is recommended that you have your water tested for lead by a licensed laboratory. 

Alternatively, water filters bearing the NSF international standard for lead reduction can be installed according to manufacturer’s instructions. Information for consumers regarding lead reducing filters can be found through a search for NSF Certified Drinking Water Treatment Units, Water Filters. If replacement is not possible, or will take time, it is recommended to use cold, flushed water for drinking and preparing food. Do not consume water from the hot water tap because heated water generally contains higher lead levels.⁴

It is important to note that boiling your water will NOT remove lead; in fact, this practice will actually INCREASE the levels of lead in your drinking water.

If I have lead service lines, can I use the water for bathing, showering, and washing dishes and clothes?

Yes. Bathing, showering, and washing dishes and clothes does not expose people to lead. Human skin does not absorb lead in water.⁴

I am still concerned about my family’s lead exposure. What should I do?

Your blood lead level is the best indication of your exposure to lead. Your doctor can do a blood test to measure your blood lead level. If you drink bottled water, be sure to check the label of the bottle to ensure the value of lead (or Pb) is 0.

If you have made an informed decision to formula feed your infant, it is important that formula is made with water below the standard, since infants are the most vulnerable to health effects of lead. The Middlesex-London Health Unit and Health Canada recommend breastfeeding exclusively for the first six months, with continued breastfeeding for up to two years and beyond.⁵ View breastfeeding for more information. If you have breastfeeding questions or you’re experiencing breastfeeding issues, please contact a Public Health Nurse at the Middlesex-London Health Unit (Monday - Friday; 8:30 a.m. - 4:30 p.m.) at:

• 519-663-5317

Additional Information

For further information on the health effects of lead, please contact the Middlesex-London Health Unit:

• 519-663-5317

For information on lead in the water, contact:

• The City of London - 519-661-4739 ext. 5541, or
• Check with your municipality or water utility.