Walmart Canada and four of its senior managers face 174 charges under the Public Health Act related to the sale of food contaminated during a wildfire that engulfed Fort McMurray, Alta., last May.

A 31-page charge sheet lists the sale of various food items ranging from chocolate bars and nacho chips to pasta, breakfast cereal, bacon and cheese. The charges, filed by Alberta Health Services, state that Walmart Canada failed to ensure that food that had been contaminated or was unfit for human consumption was not stocked or sold at its outlet in downtown Fort McMurray.

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

Court documents show the alleged violations occurred at the Walmart outlet on Hospital Street between May 24 and May 29, 2016.

Prior to allowing residents to re-enter the city, municipal and health officials repeatedly advised residents and businesses to throw out any food products other than those stored safely in cans and tins.

"I think the most alarming thing is the actual number of violations," said Keith Warriner, a food safety specialist at the University of Guelph.

"It's surprising that such a retailer like Walmart would have been open to these charges, given that they should have been proactive in disposing of the goods."

The four people charged are: Darren Kenyon; Sean Kenyon, the Walmart store manager; Michelle Payne, Walmart Canada's senior manager of food safety; and Dale Snowden, the director of disaster and response and recovery for Walmart Stores Inc.

Walmart Canada declined an interview request, but in a written statement the senior director of corporate affairs, Alex Robertson, expressed surprise at the charges.

"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."

Alberta Health Services also declined comment because the matter is now before the courts.

'Direct and avoidable risk'

However, AHS spokesman Kerry Williamson issued a statement. In the statement, AHS alleged that Walmart, "despite having received this guidance and direction from AHS, both in person and in writing ... reopened selling wildfire-contaminated food to the public."

"This was a direct and avoidable risk to the health of this community."

More than 90,000 people in Fort McMurray and surrounding communities were forced from their homes for nearly a month after the fire May 3 wildfire, which destroyed about 2,400 homes and many buildings and left layers of toxic smoke-residue behind.

Warriner said if those toxic substances got into food products, it could lead to long-term health consequences.

"A lot of them are carcinogenic, so even though they won't affect you immediately they could put you at higher risk of cancer later on, if taken over a course of time."

Under the Public Health Act, each offence carries a fine of up to $2,000.

"I would imagine the actual fine that will be administered would be for each charge, which I guess they'll fight individually," said Warriner. "But I wouldn't be surprised if it's plus one hundred thousand dollars on this case."

With files from Briar Stewart