Sobeys is pulling all romaine lettuce products from all its shelves out of "an abundance of caution," as an E. coli outbreak that has left more than 40 Canadians ill continues.

“There appears to be an ongoing risk of E. coli infections associated with the consumption of Romaine lettuce,” Sobeys said in an announcement to customers on its website Sunday.

The grocery chain said it was removing all romaine lettuce, including all Compliments-brand products containing romaine, “until further notice.” The company offered its apologies for any inconvenience.

The Public Health Agency of Canada has not ordered a recall of romaine, but Sobeys said it chose to pull the lettuce from its shelves nevertheless and will be following updates on the outbreak closely.

PHAC has advised residents in Ontario, Quebec, New Brunswick, Nova Scotia, and Newfoundland and Labrador to “consider consuming other types of lettuce” until more is known about the source of the E. coli outbreak.

It has said that based on its investigation so far, romaine lettuce has been identified as the source of the outbreak, but the cause of contamination has not been identified.

“The outbreak appears to be ongoing, as illnesses linked to romaine lettuce continue to be reported to the Public Health Agency of Canada,” the agency said on Dec. 21.

Provinces in Western Canada are not affected by the advisory.

The Canadian Food Inspection Agency is working with public health officials to determine the source of the romaine lettuce that the ill individuals were exposed to.

Earlier this week, Sylvain Charlebois, a researcher in food distribution and policy at Dalhousie University, told The Canadian Press says he is surprised by how long it is taking for a full recall to be issued.

He also noted that E. coli contamination in lettuce is particularly worrying since lettuce is rarely cooked, “so the risks are significant," he said.

So far, one death has been linked to the outbreak.