2014-2016 Bacterial Pathogens in Fresh Leafy Herbs


Fresh leafy herbs are frequently consumed by Canadians in all age groups. Unfortunately, fresh leafy herbs have been associated with numerous outbreaks of foodborne illnesses worldwide. Fresh leafy herbs can become contaminated with pathogens during production, harvest, post-harvest handling, processing, packaging and distribution. Since fresh leafy herbs are often consumed raw, the presence of bacterial pathogens creates a potential risk for foodborne illnesses.

Considering the factors mentioned above and their relevance to Canadians fresh leafy herbs were selected for targeted surveys. The purpose of targeted surveys is to generate baseline information on the occurrence and distribution of pathogenic bacteria in food. Over the course of this study (April 1, 2014 – March 31, 2016), a total of 2957 samples were collected from retail locations in 11 cities across Canada and tested for bacterial pathogens of concern (Salmonella species (spp.), Shigella and Escherichia coli O157:H7 (E. coli O157:H7)) as well as generic E. coli. Generic E. coli is an indicator of the overall sanitation conditions throughout the food production chain.

In this survey, over 99% of the fresh leafy herb samples analyzed were free of pathogenic bacteria tested for. Shigella and E. coli O157:H7 were not found in any samples. Salmonella spp. was found in 2 (< 0.1%) samples, elevated levels of generic E. coli (100 < x ≤ 1000 MPN/g) were found in 20 samples (0.7%) and high levels of generic E. coli (> 1000 MPN/g) were found in 11 samples (0.4%).

The Canadian Food Inspection Agency (CFIA) conducted appropriate follow-up activities such as facility inspections and additional sampling. Both Salmonella spp. positive samples resulted in recalls of the affected products. In cases where high levels of generic E. coli were found, no direct product action was possible. This was due to the fact that the implicated products were no longer available on the market when the sample was declared as unsatisfactory given the perishable nature of the products. In addition, in most cases it was not possible to determine the source of contamination however corrective actions were implemented by the processing facilities. There were no reported illnesses linked to the Salmonella contaminated products.

Overall, our survey results suggest that almost all fresh leafy herbs are safe for consumption however they can sporadically become contaminated with Salmonella spp. Consequently, safe handling practices are recommended for producers, retailers and consumers.

Request of Complete Report

The complete text of this report is available upon request.

The format in which you would like to receive the report (required)
Your contact information