The entire city of Sudbury, Ont., has been placed under a boil water advisory after public health officials found “adverse samples” during a check.

Public Health Sudbury and Districts said in a notice Wednesday that all residents of Sudbury and New Sudbury, as well as Falconbridge, have been impacted.

Copper Cliff, Coniston, Walden, Garson, Val Caron and area, Azilda, Chelmsford, Dowling, Skead and Onaping are not impacted, it said.

Sudbury, a major city in northeastern Ontario, has a population of roughly 190,000 residents.

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“The cause of the adverse samples is being investigated, and this boil water advisory is in effect as a precaution,” Burgess Hawkins, a manager in public health’s health protection division, said in the notice.

“We don’t believe that anyone who has consumed the water will experience any ill health effects.”

When a boil water advisory is in place, people who take water from the municipal system should not use it unless it is brought to a rolling boil for at least one minute before use. The water can be used for laundry and bathing, excluding small children who could swallow the water, officials said.

Operators with the City of Greater Sudbury have started taking additional samples of water that comes from the David Street Water Treatment Plant, and from the Falconbridge Water Treatment Plant, officials said in the notice.

They added that they will share an update when they have more information.

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