Roxann Bramlage, right, an auditor with the California Department of Food and Agriculture, monitors food safety conditions during harvesting of romaine lettuce Aug. 16 in Salinas, Calif. Bramlage checked the site as part of an industrywide effort to police food safety.

Salinas, Calif. ? Government regulators never acted on calls for stepped-up inspections of leafy greens after last year’s deadly E. coli spinach outbreak, leaving the safety of America’s salads to a patchwork of largely unenforceable rules and the industry itself, an Associated Press investigation has found.

The regulations governing farms in this central California region known as the nation’s “Salad Bowl” remain much as they were when bacteria from a cattle ranch infected spinach that killed three people and sickened more than 200.

AP’s review of data obtained through the Freedom of Information Act found that federal officials inspect companies growing and processing salad greens an average of just once every 3.9 years. Some proposals in Congress would require such inspections at least four times a year.

In California, which grows three-quarters of the nation’s greens, processors created a new inspection system but with voluntary guidelines that were unable to keep bagged spinach tainted with salmonella from reaching grocery shelves last month.

Despite widespread calls for spot-testing of processing plants handling leafy greens following last year’s E. coli outbreak, California public health inspectors have not been given the authority to conduct such tests, so none have been done, the AP review found.

“We have strict standards for lead paint on toys, but we don’t seem to take the same level of seriousness about something that we consume every day,” said Darryl Howard, whose 83-year-old mother, Betty Howard, of Richland, Wash., died as a result of E. coli-related complications.

She was one of two elderly people to die in the outbreak that began in August 2006 and also included the death of a child and sicknesses reported from more than 200 people from Maine to Arizona.

By mid-September, the U.S. Food and Drug Administration issued a two-week nationwide warning not to eat fresh spinach. Authorities eventually traced the likely source of the E. coli to a cattle ranch about 40 miles east of Salinas.

But a regulatory backlash never happened.

State Sen. Dean Florez, a Central Valley Democrat who sponsored three failed bills to enact mandatory regulations for leafy greens earlier this year, said momentum faded as the E. coli case dropped from the headlines and the industry lobbied hard for self-regulation.

“That legislation was held up waiting for this voluntary approach for food safety to see if it works,” said Florez, who is skeptical of that approach.

“It only took one 50-acre parcel to poison 200 people and bring the industry to its knees,” he said. “We don’t get why the industry would be playing this game of roulette with our food.”

Since September 2006, federal Food and Drug Administration staff inspected only 29 of the hundreds of California farms that grow fresh “stem and leaf vegetables,” a broad category the agency uses to keep track of everything from cauliflower to artichokes. Agency officials said they did not know how many of those grew leafy greens.