N.W.T. health official to release advisory on arsenic levels in Yellowknife lakes

The Northwest Territories’ chief public health officer plans to put out a health advisory to warn people about lakes near Yellowknife with high levels of arsenic.

Concerns are fishing in lakes near Giant Mine, dogs drinking lake water, says Andre Corriveau

This map, produced by the N.W.T. Department of Environment and Natural Resources, shows the level of arsenic in lakes around Yellowknife and Giant mine measured in micrograms per litre, or ug/L. Canada's drinking water guideline for arsenic is 10 ug/L. (GNWT)

The Northwest Territories' chief public health officer plans to put out a health advisory to warn people about lakes near Yellowknife with high levels of arsenic.

A study released Wednesday by the University of Ottawa found arsenic concentrations higher than the Canadian drinking water guidelines in lakes within 15 kilometres of the shuttered Giant Mine.

The guidelines recommend drinking water contain less than 10 micrograms of arsenic per litre. Some lakes sampled near Yellowknife had arsenic levels more than 13 times that.

Chief Public Health Officer Andre Corriveau says people shouldn't worry, unless they're eating contaminated mud or have been drinking contaminated water daily for years.

"Even if you're 10 times above the drinking water guidelines, those are based on a lifetime of consumption," he said.

"You're talking about 20, 25 years of daily consumption. So a short period would have been probably unlikely to have noticeable health effects."

Many of the lakes affected are northwest of Giant Mine, along the new bypass road the territory opened two years ago.

Corriveau doesn't believe there's much fishing or camping off that road, but said people should not eat any fish caught in those lakes.

He also warned against letting dogs drink from those lakes.

Corriveau's advisory is expected to be released in the coming weeks and he said it will include a map "that will be fairly descriptive that people can use as a reference."


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