CBC MARKETPLACE: HEALTH » LEAD
Lead in drinking water
Broadcast: March 27, 2001 | Producer:
Ines Colabresel; Research: Leonardo Palleja & Jenny Wells
Wendy Leigh-Bell of Hamilton, Ontario,
was warned not to drink her water after tests found high
lead levels in her drinking water |
Lead is dangerous to everyone and particularly to children.
It can cause learning disabilities and lowered IQ. So for
decades Canadians have been taking steps to lower the amount
of lead in our tap water. We have had some success.
But lead in drinking water remains a problem for many Canadian
families. Part of the reason may be because of the way we
test for lead.
Across the country, Canadians have spent hundreds of millions
of dollars digging up streets and sidewalks to replace water
pipes that leach lead into drinking water. But the work has
just begun. It will take years and cost millions more to replace
old lead pipes with copper.
Two years ago Wendy Leigh-Bell watched more than just her
children digging up the front yard. The water pressure in
her home had reached an all-time low. That is sometimes a
sign of old pipes.
Barbara McElgunn of the Learning
Disabilities Association of Canada maintains there is
no safe level for lead exposure |
Leigh-Bell decided to have her water tested. Not long afterward,
city officials called her at home.
"We received a phone call that we ought not to drink
the water…because we had a level that was three times
the allowable limit for lead," Leigh-Bell told Marketplace.
The house still had lead pipes coming from the street. The
city replaced part of the pipes and the family paid $600 to
get the rest removed. To be safe, they now drink only bottled
water.
Lead has a toxic effect on the brain, especially for young
children whose brains are still developing.
Barbara McElgunn of the Learning Disabilities Association
of Canada says that reduced IQ is just one result of lead
exposure. She maintains there is no safe level for lead.
The effects of lead that scientists and pediatricians are
most concerned with now go beyond reduced IQ. There are concerns
arising from research into the effect of lead on emotional
reactivity, aggression, social confidence and social functioning.
"It illustrates
the fact that everybody's at some risk," says University
of North Carolina lead expert, Dr. Richard Maas |
Lead in our water is not a new problem. In 1988, Marketplace
reported on the danger of lead in school water supplies.
The report caused Canadian officials to lower the maximum
allowable lead level for drinking water.
But what is the state of the lead in Canada's drinking water
today? Marketplace tested water from 50 homes across the country.
We sampled water from homes in:
- Saint John, New Brunswick
- Toronto
- Hamilton
- Winnipeg
- Vancouver
Half the homes were built before 1970, half were built after
1970.
The results? Fifteen of the fifty homes had lead levels above
the national guideline. One even had levels at 250 times the
maximum allowable limit.
Most of the problems came from homes built before 1970. Of
the 25 homes we tested that were built before 1970, eleven
had high lead levels.
We told Dr. Richard Maas about our test results. He
For more on our interview with Dr
Richard Maas and details of his offer to test your water,
click here.
For water testing labs closer to home, go to our story
on Home
Water Filters. |
is a scientist at the University of North Carolina and an internationally
renowned specialist on lead in water.
"It illustrates the fact that everybody's at some risk,"
Maas told Marketplace. "If you're in an older home,
you're probably at more risk."
When should your water should be tested? While you're sleeping,
water is at rest in your pipes for hours. If there's lead
anywhere in your system, it will leach into the water. It
takes just two hours for standing water to absorb a lot of
lead.
If there is lead in your water, you are most likely to
find it at first draw; the water that comes out when you
first turn on the tap. There's usually less lead when the
tap has been run or flushed, as it's called in the industry.
For each of the 50 homes in the Marketplace study,
we tested the water twice: first thing in the morning and
once after the water had been run for three minutes.
Each of the 15 homes with high lead levels got those numbers
when the sample was taken at first draw, before the water
was run. After the water had been run for three minutes, most
homes were free of excessive lead. But two still had problems,
even after the water had been run.
In the United States, if you're assessing lead contamination
of drinking water you are required by law to take water from
the first draw.
In Canada, when federal and provincial governments test drinking
water for lead, they do so only after it's been run for three
minutes. That's a strategy that's gained some critics.
"If you don't want to find the lead problem that's
a good sampling strategy for doing that," Dr. Richard
Maas said.
Dave Green, Health Canada's representative on the federal-provincial
committee that drafts the guidelines for Canada's drinking
water, says the key is to determine the average amount of
lead that is in the water a person consumes.
Health Canada's Dave
Green says regulations for testing for lead in water in
Canada are adequate. Canada does not require samples to
be taken at first draw as the United States does |
Green disagrees with the suggestion that water should be
tested at first draw, given that our tests showed that flushing
the water reduced lead levels in 13 of the 15 samples.
"I would say that one method of trying to estimate how
much lead is consumed by people in their drinking water in
the way we have it on a flushed sample is just as valid as
taking first flushed samples, as the U.S. does," Green
said.
Richard Maas disagrees.
"If you do all your sampling after a three to five minute
flush, then you are greatly underestimating the average concentration
of lead in the water because you're only looking at flushed
water," Maas told Marketplace.
Dave Green notes that his department tries to publicize as
much as possible that people should let their water run for
three to five minutes in the morning, before drinking it.
He admits, though, that he has no idea whether most people
realize that.
As for Wendy Leigh Bell, we re-tested for lead in her house
tap water.
It came in at 3.5 times the allowable maximum.
The lead could be coming from any one of several sources:
more lead pipes, lead solder on the copper or even lead in
the faucet. It's tough to trace.
NEXT: Results
of Marketplace tests of lead in tap water »
^TOP
|
CBC does not endorse and is not responsible for the content of
external sites. Links will open in new window.
