The New York Times reports this morning that two major American companies, Costco Wholesale and Beef Products Inc., have gotten tired of waiting for regulators to act on non-O157 STECs (shiga-toxin producing E. coli) and are proceeding with their own plans to protect customers.

Last month, Costco, one of the nation’s largest food retailers, quietly began requiring its suppliers of bagged produce, including salad greens and mixes, apple slices and baby carrots, to test for a broad range of toxic E. coli.

“We know this is where we have to go and there’s no reason to wait,” said Craig Wilson, the food safety director of Costco. In the last two weeks, he said, most produce suppliers have added a test that can detect the strain from the European outbreak as well (E. coli O104).

The company also plans to test all of the ground beef sold at its warehouse stores. Costco operates a large ground beef plant in Tracy, Calif., and Mr. Wilson said the plant recently began evaluating testing procedures to detect the broader range of E. coli in the hamburger it makes and the beef trimmings that go into it.

As an added step, the company plans to ask suppliers of the trimmings to do their own testing, starting later this summer, he said.

Costco’s new testing requirements come as the federal government continues to drag its feet on what to do about the expanding E. coli threat. After four years of study, the United States Department of Agriculture finished drafting rules in January for how the industry should handle the “Big Six” E. coli in ground beef.

But the proposal has been stalled within the Office of Management and Budget, which reviews most federal regulations before they are released. Details of the proposal are confidential, but many in the industry expect that the rules would require testing or even make it illegal to sell ground beef that contained the additional strains of toxic E. coli.

The landscape is changing partly because tests created by U.S.D.A. scientists that can quickly pinpoint the presence in food of the “Big Six” E. coli are now being developed for commercial sale by test-kit companies. Some kits are already on the market.

A table of non- E. coli O157 STEC outbreaks is available at http://bites.ksu.edu/nonO157outbreaks