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Study finds elevated levels of mercury, chromium in Porcupine Lake fish

There are now new eating recommendations for eating fish from the lake
2020-07-23 Bannerman Park2 MH.
The view of South Porcupine from the Porcupine Lake lookout in Bannerman Park. Maija Hoggett/TimminsToday

A Ministry of Environment, Conservation and Parks (MECP) study on fish in Porcupine Lake has revealed elevated levels of mercury and chromium, according to the Porcupine Health Unit.

The monthly recommended amount of fish people should be eating from the lake has been updated. For two species — white sucker and yellow perch — the new advisory says women of child-bearing age and children under 15 should not be eating the fish at all.

The MECP study was done in June 2019.

"The results demonstrated elevated concentrations of mercury and chromium in various species of fish. This study has prompted the Government of Ontario to update consumption advice in the publication Guide to Eating Ontario Fish," reads the health unit news release.

"Previous advisories, due to the elevated levels of mercury, for Northern Pike, Walleye and White Sucker have become more restrictive and there is a new advisory for Yellow Perch."

The new recommendations for the general population are:

  • Northern Pike (40-60 cm) - two meals per month (previously four)
  • Walleye (40-65 cm) - one meal per month (previously two)
  • White Sucker (35-50 cm) - one meal per month (previously eight). Women of child-bearing age and children under 15 should not be eating it, whereas the previous monthly limit was four.
  • Yellow Perch (25-30 cm) - one meal per month. Women of child-bearing age and children under 15 should not be eating it, whereas there was no previous limit.

"The MECP has committed to investigating the potential sources of chromium in Porcupine Lake and will share those results with the Porcupine Health Unit once available. The Porcupine Health Unit will continue to actively follow reported information and provide updates to the public regarding potential concerns for public health," reads the news release.

According to Ontario's guide to eating fish, "chromium is a metal found in fish tissue but only occasionally at levels requiring consumption restrictions." 

For mercury, it explains fish eliminate it "at a very slow rate" and walleye and pike usually have the highest levels.

"Anglers using any Ontario lake should consult the interactive Guide to Eating Ontario Fish map online for advisories and track their monthly intake of fish based on the specific advisories for that water body," said Dr. Lianne Catton, PHU medical officer of health in a news release.


Maija Hoggett

About the Author: Maija Hoggett

Maija Hoggett is an experienced journalist who covers Timmins and area
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