A law firm is testing the waters to see if there's interest among Fort McMurray residents who may have bought wildfire-contaminated food from the downtown Walmart.

Calgary-based Higgerty Law announced Saturday on its website that it may launch a class-action lawsuit on behalf of Fort McMurray customers who have purchased contaminated food in the weeks after the wildfire. The law firm is asking people impacted to complete an online questionnaire.

"Whether you have symptoms or not, many of the contaminants are carcinogenic," the post reads. "So even though they won't affect you immediately they could put you at higher risk of cancer later, if taken over a course of time."

Walmart Canada and four of its senior managers face 174 charges under the Alberta Public Health Act related to the sale of food contaminated during the wildfire, which engulfed the city last May.

A 31-page charge sheet alleges the store sold various contaminated food items, ranging from chocolate bars to bacon and chicken.

The charges also allege that Walmart Canada failed to ensure that food that had been contaminated or was unfit for human consumption in the wake of the wildfire was not stocked or sold at its location in downtown Fort McMurray.

Four additional charges allege that Walmart lied to public health inspectors by saying it was not selling food that had been contaminated in the fire.

Walmart Fort McMurray Wildfire

A look inside Fort McMurray's Walmart on June 8, 2016, days after residents returned to the city following the wildfire. (Radio-Canada)

Before residents were allowed to re-enter the city after the wildfire, health officials repeatedly advised residents and businesses to throw out any food products not stored safely in cans and tins.

Higgerty Law's general counsel, Clint Docken, said a handful of customers have already contacted the law firm.

"We have talked to people that have suffered some health issues," Docken said in an interview. "Which they are blaming on groceries that they purchased in Walmart."

Walmart accused of selling contaminated food after Alberta wildfire2:05

Alex Robertson, Walmart Canada's senior director of corporate affairs, reiterated a statement the company issued on Friday.

"We, at all material times, and during an unprecedented crisis, worked very closely with both food inspectors and the crisis management team of the Regional Municipality of Wood Buffalo to re-open the store as soon as reasonably possible in an effort to support and meet the critical needs of the community" he said.

Walmart said the company follows strict procedures to ensure customer safety.

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