Leafy greens are 'major source' of foodborne illnesses and costs, study finds

Article By Laura Brehaut Published May 27, 2024
Article Source: Leafy greens are a 'major source' of foodborne illnesses, study finds | National Post

Lettuces are the worst offenders, linked to over 75.7 per cent of leafy green foodborne illnesses and 70 per cent of costs

Handling and cooking poultry properly is one effective way to reduce your risk of foodborne illness. A recent study published in the Journal of Food Protection highlights a seemingly less likely source — leafy greens.

Researchers at The Ohio State University found that contaminated leafy greens cause 2,307,558 estimated illnesses and cost US$5.28 billion annually in the United States alone.

“Leafy green vegetables are a major source of foodborne illnesses. Nevertheless, few studies have attempted to estimate attribution and burden of illness estimates for leafy greens,” write Xuerui Yang, the paper’s corresponding author, and Prof. Robert Scharff.

The study suggests that 10 subcategories of leafy greens, including iceberg, romaine and other lettuce, spinach, cabbage, kale, parsley, arugula and “mixed” greens such as spring mixes, mesclun and similar salads, account for up to 9.2 per cent of known pathogen-caused foodborne illnesses.

Lettuces are the worst offenders, linked to over 75.7 per cent of leafy green food poisoning cases and 70 per cent of costs.

According to a 2020 study published in Emerging Infectious Diseases, 32 outbreaks of E. coli infections linked to contaminated leafy greens occurred in the United States and Canada between 2009 and 2018. The Canadian Food Inspection Agency reports that this decade of outbreaks resulted in 16 recalls in Canada. Eight people in North America died, 420 were hospitalized and 1,212 fell ill.

Most people aren’t eating enough vegetables, so fear of foodborne illness isn’t helping matters. (A 2021 Dalhousie University study suggests that only 29 per cent of Canadians buy the recommended amount of produce, let alone eat it.) Health Canada underscores that handling and preparing food properly can prevent many of the more than four million cases of foodborne illnesses each year.

Instead of avoiding leafy greens, prepare them properly. Wash your hands and all utensils, countertops and cutting boards before you start. Health Canada recommends discarding the outer leaves and washing the greens thoroughly under cool tap water. The agency advises against soaking produce in the sink since it can become contaminated with bacteria.

Greens are prone to contamination since they grow close to the ground. Health Canada explains that in addition to potential contaminants in the soil, such as improperly composted manure and tainted water, they can become contaminated by bacteria during and after harvest, at the grocery store, in the fridge or during food preparation.

Prof. Lawrence Goodridge, director of the Canadian Research Institute for Food Safety at the University of Guelph, who was not involved in the study, said in a March interview with the National Post: “We see this during barbecue season, for example, when people have ground meat — hamburger, ground poultry or whatever. They put that on the grill and use the same utensils and the same plate with the raw meat juice to put on their tomatoes, lettuce and onions. That causes cross-contamination.”