Eating a hamburger in the U.S. comes with the risk that it might contain fecal matter, based on research performed for Consumer Reports.

“There’s no way to tell by looking at a package of meat or smelling it whether it has harmful bacteria or not,” said Urvashi Rangan, executive director of the Center for Food Safety and Sustainability at Consumer Reports. “You have to be on guard every time.”

The consumer organization bought 300 packages of ground beef totaling 458 pounds of meat from a variety of stores and had it tested for bacteria. The results showed all 458 pounds contained bacteria that indicated feces came into contact with the meat at some point.

Specifically, the bacteria detected were enterococcus and/or nontoxin-producing E. coli, which can cause blood or urinary tract infections, Andrea Rock reported. Nearly 20% of the test meat contained C. perfringens, which is responsible for causing about 1 million cases of food poisoning each year. Another 10% had a strain of S. aureus bacteria that produces a toxin that makes people ill and can’t be destroyed by cooking. 

Only 1% of the samples contained salmonella, which can still be a significant amount considering Americans eat billions of pounds of ground beef annually. Salmonella each year causes about 1.2 million illnesses and 450 deaths in the U.S.

Consumer Reports found that, not surprisingly, the beef most likely to contain bacteria, particularly antibiotic-resistant bacteria, was that that came from cattle raised on conventional feedlots. Beef from sustainably raised cattle, ones that spend their entire lives in pastures, was less likely to contain bacteria.

-Noel Brinkerhoff, Steve Straehley

To Learn More:

How Safe Is Your Ground Beef? (by Andrea Rock, Consumer Reports)