Canada's food inspection agency announced on Friday it was restricting imports of romaine lettuce from parts of the US state of California linked to several recent outbreaks of E. coli food poisoning.

Importers will have to prove that any romaine brought into Canada does not originate from the Salinas Valley in California -- the source of the past poisonings.

They can also provide laboratory certification of "below-detectable levels of E. coli" in romaine from the region, the Canadian Food Inspection Agency (CFIA) said in a statement.

The import restriction, which also applies to mixed salads containing romaine, takes effect October 7 and will last until the end of the year.

Canada has effectively banned the import of romaine lettuce from parts of Since 2016, romaine lettuce from California has been linked to outbreaks of E. coli illnesses in the US and its northern neighbor
Canada has effectively banned the import of romaine lettuce from parts of Since 2016, romaine lettuce from California has been linked to outbreaks of E. coli illnesses in the US and its northern neighbor GETTY IMAGES NORTH AMERICA / BRENT STIRTON

Since 2016, romaine lettuce from California has been linked to outbreaks of E. coli illnesses in the US and its northern neighbor, including dozens of hospitalizations and at least one death in Canada.

Food safety investigations by both countries identified the Salinas Valley growing region as a recurring source of the outbreaks.

"To mitigate risk in the event of another outbreak this fall, the Canadian Food Inspection Agency is implementing temporary import measures aimed at preventing contaminated food from entering the marketplace," the CFIA said in a statement.

The announcement comes one week before the Canadian Thanksgiving holiday.

Canada