DENVER (CBS) – Shoppers beware – consumer advocates say grocery stores are not doing enough to warn customers about recalled food. U.S. PIRG is calling on retailers to do more to protect people from food-borne illnesses that sicken 48 million Americans every year.

In 2018, more than 6 million pounds of ground beef were recalled over fears it could be contaminated with salmonella. But months later people were still getting sick – they had apparently frozen the meat and later ate it, never knowing about the recall.

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“Twenty-five percent of people who got sick from the contaminated beef got sick after the recall occurred,” U.S. PIRG’s Adam Garber said.

The FDA and USDA post recalls and depend on the media to get the word out, but it doesn’t reach everyone. Now U.S. PIRG is calling on grocery stores to help.

“Using supermarkets to warn the public about these dangerous food borne illnesses would help seriously protect public health and make sure people don’t end up in the hospital or worse,” Garber said.

He worked on a report that graded 26 major grocery stores on how the public is alerted of potentially dangerous food that was previously sold. Only four (Harris Teeter, Kroger, Smith’s and Target) received a passing grade – 22 others failed.

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Read The Report

U.S. PIRG says more stores should use contact info from their loyalty programs to warn customers by email or phone about recalls. Currently about 58% of supermarkets do. The group also says stores should prominently display signs.

“They could be at the cash register or the shelving units or on the front door as you enter or exit the door,” Garber said.

The National Grocers Association said in a statement that “Over the past decade, companies have improved upon the recall response time,” adding “in many instances the product is stopped in the supply chain and never even makes it into the shelves.

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U.S. PIRG is also calling on the FDA to enact new rules to make the recall process more effective at warning customers before they get sick.