Are Food-Testing Labs Failing Us?

If there’s one thing we can all agree on, it’s that no one should die because they ate a cantaloupe. Or a spinach salad. Or a hamburger. Or a peanut butter sandwich. But sadly, the names of pathogens like E. coli, salmonella, listeria and campylobacter—and the disease and death they can cause—have become part of the American lexicon.

And it doesn’t look as if they’ll be leaving our public conversation over food safety anytime soon: A new report presented at the American Society for Microbiology’s general meeting in Denver this week shows that food microbiology laboratories, which test raw ingredients and food samples for a variety of producers and companies, routinely report food is safe when in fact it isn’t.



“The study involved about 40,000 food laboratory proficiency tests conducted over the last 14 years and showed that food microbiology laboratories that are supposed to identify pathogens in food submit a disturbing number of false negative and false positive results,” writes Alexanddra Sifferlin for Time. The new report by the American Proficiency Institute (API) “revealed worrisome gaps in the ability of food laboratories to detect or rule out the presence of common disease-causing bacteria.”

How frequent are the false reports? Often enough to warrant concern. Food laboratories reported false negatives for campylobacter 9.1 percent of the time. For salmonella, the figure was 4.9 percent. When it came to false positives, the numbers were better—3.9 percent for salmonella and 2.5 percent for E. coli and L.monocytogenesbut still troubling.

“There is concern when laboratories report that pathogens are not found in a food sample, when in fact they are there,” said Christopher Snabes, lead author on the study in a statement.

Indeed, according to the Centers for Disease Control and Prevention, one in six Americans become ill from food-related illness, and approximately 3,000 die.

What’s important to remember is that food testing isn’t designed to ensure that each and every bite you take is safe. Instead, it’s meant to monitor the processes and assist in outbreak investigations when health officials are trying to track down the pathogen responsible for making people sick.

The Food Safety Modernization Act (FSMA)—signed into law by President Obama in January 2011 but not yet fully enacted—does address laboratory testing specifically, but according to API, food laboratories are not required to assess the accuracy or quality of their tests. Until final FSMA rules are adopted (which is still a ways into the future; comments are being accepted until September 16), laboratories that choose to work with API do so voluntarily.

Related stories on TakePart:

• Sorry, Your Salad Will Make You Sick—and That Chicken Might Kill You

• A Decade of Foodborne Illness: What You Didn’t Know

• Is Listeria Lurking in Your Camembert?

Clare Leschin-Hoar covers seafood, sustainability and food politics. Her work has appeared in Scientific American, The Wall Street Journal, Grist, Eating Well and many more. @c_leschin |