The U.S. government has gone a step further and demanded retailers and restaurants remove the leafy green from store shelves and stop including it in meals.
The E. coli outbreak, which the U.S. Food and Drug Administration said likely originated in California, has been linked to the illnesses of 19 people in Ontario, Quebec and New Brunswick and 32 cases in the U.S.
The scare is the second high-profile contamination of romaine lettuce with E. coli this year. And the U.S. Centers for Disease Control and Prevention (CDC) said the current outbreak shares a genetic fingerprint with one tied to romaine lettuce in the U.S. and Canada 2017.
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Why does this keep happening?
E. coli is bacteria that live in the intestines of cattle, poultry and other animals, and it seems to seep into romaine lettuce crops … a lot.
Problems with romaine lettuce have become so frequent, the FDA announced a “special surveillance” plan to sample lettuce for contamination in early November.
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Jason Tetro, microbiologist and author of The Germ Code, said E. coli has an “annoying” ability to get into romaine lettuce. And the lettuce is usually contaminated from dairy farms and cattle feedlots located near the growing areas.
“The canals used to irrigate the lettuce are usually upstream from a cattle farm, which has manure that can run off into the water,” he said, which leads to contaminated crops.
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And because we don’t cook the greens, it can be one of the riskiest options when it comes to food safety. Cooking destroys bacteria, whereas salads are often simply rinsed and served. And rinsing does not get rid of E. coli.
“Salad greens are a particular culprit in foodborne illnesses as it’s eaten raw. Cooking can cover a myriad of sins,” Tamar Haspel, a food and science writer with the Washinton Post, said.
E. coli problem could last for years
Because Canada imports so much romaine lettuce from California, Tetro predicts the problem with E. coli will last for years.
The key to a bacteria-free vegetable is clean water, he said. And although California recently passed a law that requires farmers to have clean water and testing in irrigation systems, it does not have to be implemented until 2022.
“This is going to happen again,” Tetro said, adding that consumers may want to start thinking about an alternative green to have in their Caesar salads.
Is it time to ditch romaine lettuce?
If the problem of E. coli and romaine lettuce persists, Haspel and Tetro said there are other options on the table.
Haspel, who wrote a column for the Washington Post a few years ago called Why salad is so overrated, argues that leafy greens, like iceberg and romaine lettuce, are made up of mostly water and don’t pack the nutritious punch that many people may think they do.
She said it’s not that romaine lettuce isn’t healthy (it’s a good source of folate and vitamin K); it’s that you have to eat a lot of it to get the nutrients.
“If you took all the romaine out of your salad and cooked it down, you would see it cooks down to nothing. A huge heap is really only three tiny bites,” Haspel said, adding that because romaine is made up of 95 per cent water, it’s difficult to eat enough of it to make it substantial.
Tetro said there are a variety of other leafy greens that not only are healthier but don’t run the E. coli risk.
“Eat kale,” Tetro said. “You don’t really see any outbreaks like this in kale.”
Haspel said consumers should start looking at other greens you can cook, like kale, chard and collards.
“Collard greens are 90 per cent water, which is still a lot, but it’s twice as much plant matter than lettuce,” she said.
“If people don’t like to cook, I would point them to frozen food aisle because greens freeze really well, and you can add them into pasta sauces.” She added that although she is in no way a “romaine hater,” she believes we should start thinking about it as a luxury food.
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