The week I spent in the hospital fighting food poisoning ranks among the worst weeks of my life. I was miserable from the nonstop vomiting and diarrhea, and, because I was pregnant with twins at the time, I was also terrified about what the infection might be doing to my babies.

So I pay attention when there’s news about food poisoning. And the latest news is a shocker, because it concerns something that people generally think of as wholesome and healthy—farmers’ markets. These markets are popping up all over, partly in response to the “eat local” movement. After all, foods grown closer to home don’t have the negative environmental impact that comes with long-distance trucking, and they’re generally fresher, too. That’s why people are flocking to farmers’ markets for fruits, veggies, eggs, meats, dairy foods and more.

But when it comes to one particular type of food, buying from a farmers’ market could set you up for your own nasty bout of food poisoning. According to a new study, the raw chickens sold in farmers’ markets tend to be very high in dangerous bacteria.

Given that foodborne ailments account for 48 million gastrointestinal illnesses, 128,000 hospitalizations and 3,000 deaths each year in the US, it’s important to know how to lower your risk.

COUNTING YOUR CHICKENS’ BACTERIA

Researchers from Pennsylvania State University’s department of food science bought 100 raw, whole chickens from five large-chain supermarkets—50 nonorganic and 50 organic birds. They also bought 100 raw, whole chickens from 21 different poultry vendors at farmers’ markets around Pennsylvania. Regardless of any claims made on their labels, the chickens purchased at farmers’ markets did not have any third-party or government certifications to back those claims (e.g., “organic”), so they were grouped into one category for testing purposes.

All the chickens were transported back to the lab in coolers and then rinsed with a sterile solution. But instead of letting the used solution go down the drain, this “rinsate” was collected and analyzed.

Now the shocking part: The farmers’ market chickens were by far the worst in terms of contamination. Comparisons…

Farmers’ market: 90% of chickens tested positive for Campylobacter bacteria…and 28% tested positive for Salmonella. Both of these types of bacteria can readily cause food poisoning.

Supermarket/organic: 28% of chickens tested positive for Campylobacter…and 20% tested positive for Salmonella.

Supermarket/nonorganic: 52% of chickens tested positive for Campylobacter…and 8% tested positive for Salmonella.

More grossness: The researchers also looked for various microbes known as “hygiene indicators,” such as E. coli, that typically are measured to assess the effectiveness of sanitation practices and potential fecal contamination on meat and poultry products. It turned out that the birds from farmers’ markets were much higher in these hygiene-related microbes than conventional nonorganic grocery store chickens (and, surprisingly, the organic supermarket chickens also had high counts).

Typically, conventional processors use several antimicrobial interventions to remove these bacteria or reduce their concentration. So the study results suggest that farmers’ market vendors may not be using antimicrobial practices in their processing. While organic chicken processors no doubt are using organic antimicrobial interventions, the researchers said, the higher E. coli counts seen in organic chickens could be due to issues with storage, packaging and/or transport.

PLAYING CHICKEN WITH YOUR HEALTH

According to federal law, poultry processors who process 20,000 birds or fewer each year are exempt from the daily or bird-by-bird USDA inspections that are meant to ensure that preventive measures are taken to reduce bacterial contamination. Clearly the process isn’t working well, since even a large portion of supermarket chickens harbored bacteria—but the inspections probably help somewhat. The researchers for this study can’t say for sure that the small-scale farmers’ market poultry vendors were not inspected by the USDA, but it’s unlikely that they were.

Also, since this study looked only at farmers’ markets in Pennsylvania, we don’t know whether the scope of the problem is the same in other states, so additional research is needed. Still, there’s no reason to suspect that Pennsylvania would be uniquely problematic in this regard.

Stay safe: You may think that rinsing your chicken before cooking it will wash away bacteria—but in fact, rinsing poultry is the worst thing you can do. It isn’t very effective at removing bacteria…and it sprays contaminated water droplets around the kitchen, where the microbes can survive for days or even weeks. For more information on that topic plus additional food-safety tips, read “Don’t Rinse the Chicken…and Other Secrets to Avoiding Food Poisoning.”

The researchers hope to develop food-safety training programs for poultry vendors who sell their wares at farmers’ markets. But until such programs are in place, you may want to stick to produce when you visit your local farmers’ market…or be very, very careful to cook your farmers’ market chickens (as with all poultry, including organic) to a minimum internal temperature of 165°F to kill off bacteria.