Heavy metal soil contamination found at 24 homes in St. Boniface

The yards and gardens of at least 24 properties in St. Boniface have tested positive for heavy metal contamination that exceeds national guidelines, CBC News has learned.

Almost 130 letters from the University of Manitoba were hand delivered to residents in the area of Mission Industrial Park on Friday, announcing the results of soil samples that were taken from gardens in August of 2017.

Twenty-four of those letters warned that heavy metal levels in their samples exceeded Canadian Council of Ministers of the Environment guidelines for soil quality.

In one letter obtained by CBC News, the resident's soil sample was found to have 204 milligrams of lead per kilogram of soil; the acceptable level of lead according to the CCME is 140 milligrams per kilogram.

"The bottom line is [these results] will inform the residents in terms of the precautions they need to take if they are to grow vegetables in those soils," said Francis Zvomuya, the University of Manitoba professor who has led the collection of samples since 2017.

"Residents need to be aware and be aware of what practices they can use to reduce the risk of exposure to those contaminants."

'A public health concern': minister

Questions surrounding the quality of the soil in the industrial area of St. Boniface came to light last summer, when Shirley Thompson, an associate professor with the Natural Resources Institute at the University of Manitoba, took soil samples in the area.

She found high levels of lead, cadmium, copper and zinc, among others.

The researchers from the University of Manitoba then started collecting soil samples from more than 100 residential properties as well as parks, ditches and streams in the areas bordering Mission Industrial Park.

Preliminary results released in October showed "there was no reason for concern," Manitoba Sustainable Development Minister Rochelle Squires said.

"That message is likely one that they (researchers) will continue to deliver. What we had said then [in October] is undoubtedly there is some need to analyze the soil here and take a look at what we're dealing with," Squires told CBC News on Monday.

"And we've analyzed that soil and now we're finding that there are some properties in exceedance."

Squires has promised to work with residents to monitor the soil and says her government will continue to make the results of the tests public.

"It's of course a public health concern — one that we take very seriously," Squires said.

"This is not exclusive to St. Boniface. This is not exclusive to Manitoba. It is a North American-wide problem."

She said her government was unable to issue a public release on the results because of Tuesday's byelection in St. Boniface.

St. Boniface residents are electing a new member of the legislative assembly Tuesday.

"And of course as you know I can't do any any type of press conference or press release. And so I was unable to do that and that does concern me and it concerns me then and I do look forward to sharing with all interested parties fully the results of what we found," she said.

Of the 24 properties flagged for high heavy metal levels, 18 had lead levels that exceeded national guidelines, six had high zinc levels and four tested positive for copper. Some samples had more than one metal exceedance.

Cause of contamination unclear: prof

Squires and Zvomuya have the same message for St. Boniface residents: wash your vegetables.

"Leafy vegetables, you need to wash them," Zyomuya warned, adding residents should peel root vegetables and wash their hands after gardening.

"Lead exposure causes some health risks, especially in toddlers and infants. It can result in problems with the development of the brain and other elements as well."

He cannot say for certain what caused the contamination.

"That is a question we cannot answer based on the sampling that we did," he said.

"Lead comes from a lot of different sources. It can be from industrial activity. It can also be in old neigbourhoods when old paint was used."

Lead gasoline also can be a factor, he said.

He has pledged to continue to look at the data and see what patterns emerge.

Squires said the province has further specific plans for the area around the industrial park but cannot elaborate because of the current byelection blackout that prohibits government from announcing new projects.