Toronto's public works chair is telling residents to get their tap water tested if they don't feel comfortable consuming it in light of a report that is raising concerns about unsafe levels of lead.

Coun. Denzil Minnan-Wong said public works staff assured him Toronto's drinking water is safe for consumption and the city is forging ahead with measures to reduce the amount of lead in the system.

The city says the drinking water is continuously tested during and after treatment, and the problem rests with lead water service pipes that supply homes built before the mid-1950s. The city recommends homeowners replace the lead pipes.

Minnan-Wong faced questions about water quality after a Toronto Star report found 13 per cent of household tests conducted over the past six years showed unsafe levels of lead.

The newspaper's finding is based on an analysis of data compiled by the city after Torontonians submitted about 15,000 samples from their water taps between Jan. 1, 2008 and Jan. 28, 2014.

A majority of the unsafe levels were found in aging neighbourhoods where infrastructure is old and real estate values are typically high, the Star reported Tuesday.

High Park, Lawrence Park, the downtown south Annex and sections of East York had the largest concentration of dangerously high levels.

Minnan-Wong questioned the precision of the data.

"I’m not sure that the data there was completely up to date. It was a little old," he told CP24 reporter Karman Wong.

Lou Di Gironimo, general manager of Toronto Water, said the findings are not a surprise because staff have been following the issue for years and they are taking steps to reduce the lead concentration.

Staff are replacing 5,000 city-owned pipes every year and adding a food-grade phosphate to the water treatment process, Minnan-Wong said.

Homeowners who go through the costly process of replacing a lead service pipe can then apply to have the city-owned portion of the pipe, which runs from the water main to the property line, replaced.

Lead water service pipes are commonly found in houses built before the 1950s. Houses built between the mid-1950s and 1989 likely don't have a lead water pipe, but there may be lead in faucets or valves or the solder used to connect pipes.

Lead can enter drinking water while passing through these pipes and fixtures. The city says there are still an estimated 40,000 homes with lead pipes.

Exposure can affect the growth of the brain and nervous system, and those who are at greater risk include pregnant women, children under six and infants who consume formula made with tap water.

Di Gironimo said people who have a lead pipe in their home should replace it if they have young children or are thinking about having children.

Torontonians who don't know if their home has a lead pipe should first find out if the house was built before the mid-1950s.

If the pipe that goes into the water meter is grey, scratches easily and does not sound hollow it may be lead, the city says. Any licensed plumber or home inspector can confirm if the pipe is lead.

If that is the case, Toronto Public Health recommends replacing both portions of a lead pipe - the city-owned portion and the portion on the homeowner's property.

People who live in a home with a lead pipe should install an end-of-tap water filter that has been certified by the National Sanitation Foundation.

Free water testing kits are available to Torontonians who live in a single family home built before the mid-1950s. People can obtain a free kit by calling 311.

Apartment buildings and other multi-residential buildings with more than six units do not have lead water pipes, regardless of age, the city says.

Toronto Public Health offers the following advice for people to reduce their exposure to lead in drinking water:

  • Use only cold water for drinking, cooking or preparing baby formula. Cold water is less likely to be contaminated.
  • For baby formula: pour cold filtered tap water, boil it and let it cool. Use within 30 minutes.
  • Let tap water run cold to the touch before drinking it, especially if it has been standing in the pipes for a few hours.
  • Conserve water by using a pitcher to store water in a refrigerator rather than flushing the pipes each time you need drinking water.
  • Showering and flushing toilets can also minimize the need to flush taps.
  • Boiling water will not remove lead.

Additional information can be found on the city's website.

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