Yesterday, I was speaking to a lawyer for a large leafy green producer not involved in this recent Cyclospora outbreak that is related to bagged mixed leafy greens and was reminded of an article that ran in the Journal of Food Protection earlier this year entitled: Detection of Cyclospora, Cryptosporidium, and Giardia in Ready-to-Eat Packaged Leafy Greens in Ontario, Canada by Dixon, Parrington, Cook, Pollari and Farber.
For your typical food safety lawyer insomniac, it is good reading at 3:00 AM. Here are the highlights. The full article is worth the read (need to be a member of IAFP), and is a great reminder how little we pay attention to the tings we should.
The study reported on the presence of Cyclospora, Cryptosporidium, and Giardia in precut salads and leafy greens purchased at retail in Ontario, Canada. A total of 544 retail samples were collected between April 2009 and March 2010 and included a variety of salad blends and individual leafy greens. Most of these products were grown in the United States, with some from Canada and Mexico.
- Cyclospora was identified in nine (1.7%) samples.
- Cryptosporidium was identified in 32 (5.9%) samples.
- Giardia was identified in 10 (1.8%) samples.
The authors concluded a relatively high prevalence of all three parasites was found in packaged, ready-to-eat leafy greens. This, along with the fact that all isolates tested represented species and genotypes commonly reported in humans, suggested that there is a potential for transmission to consumers, particularly since these leafy greens are typically consumed raw.
The authors further suggested that, in addition to imported produce, domestically grown produce could also be a source of foodborne transmission of these pathogens and that there is a distinct seasonality in prevalence, with most positives occurring in the summer and early fall.
The source or sources of contamination of the produce tested in this study are not clear, but there is some evidence pointing to possible human origins.
The authors did not find it possible to determine the horticultural practices used in each case. Specifically, it was not known whether the ‘‘organically grown’’ produce tested in the study was fertilized through the application of composted manure and, if so, what the source of the manure was. Nevertheless, the results showed that this produce was not any more heavily contaminated with protozoan parasites than nonorganic produce.
Well, so much for paying attention to the Canadians.