By MICHAEL GARRY

In its role of supplementing government inspections, third-party food safety audits of farms and food processors are supposed to serve as a defense against outbreaks of foodborne illness. And they often do. But when they don’t, the results can be catastrophic, raising questions about how the food safety auditing system should be improved.

The latest example of an audit that allegedly failed to flag unsanitary conditions linked to an outbreak occurred last year at Jensen Farms, Granada, Colo. PrimusLabs, Santa Maria, Calif., through its subcontractor Bio Food Safety, conducted an audit at the farm’s cantaloupe packing shed in late July, days before the start of a listeria outbreak that the Food and Drug Administration tied to conditions in the shed. Yet the auditor gave the packing plant a score of 96 points out of 100, according to a report in the New York Times. Robert Stovicek, president of PrimusLabs, declined to comment for this article.

As of the beginning of February, the death toll attributed to the infected cantaloupes stood at 32, out of nearly 150 illnesses, making it the deadliest foodborne illness outbreak in the U.S. in nearly 100 years, according to Food Safety News.

Third-party audits have also come under scrutiny in several other high-profile outbreaks in recent years. For example, in 2010, a salmonella outbreak was traced to filthy conditions at two Iowa farms where hundreds of millions of eggs were recalled, though one of the farms, Wright County Egg, had received a superior rating from auditor AIB International, Manhattan, Kan., according to numerous reports.

In late 2008, AIB International also gave a superior rating to facilities operated by the Peanut Corp. of America (PCA), which were later found to be unsanitary and linked to at least nine deaths and nearly 700 illnesses.

In 2009, a spokesman for AIB told SN that its approach to auditing PCA “involved checking documents, making sure programs are in place, checking equipment at a single point in time.”

Bill Marler, an attorney with Marler Clark, Seattle, is among the sternest critics of the food safety auditing system. “Time and again this firm has represented injured people, or the families of those who died, in outbreaks where a negligent processor was given glowing reviews, only for investigating agencies later to find during unbiased, competent investigations done without the veneer of conflicting interests, that the facility in which the food was produced was not suitable for the production of [animal feed], much less food for human consumption,” he recently wrote on his online blog.

Craig Wilson, vice president of quality assurance and food safety, Costco Wholesale, takes issue with the refusal of auditing companies to offer an insurance policy on their audits in case of a recall or failure. “When there’s a failure, they will say, ‘We’re not accountable for when we’re not there,’” he said. “But they’ll say, ‘It was fine when we were there.’ It’s an interesting conundrum.”

Some critics believe there should be greater federal oversight of auditing companies. The Food Safety Modernization Act, passed a year ago, expanded the role third-party auditors can play in authorizing the safety of some imported foods, but it does not address regulating private auditors.

But Amanda Hitt, director of the Food Integrity Campaign for the Government Accountability Project, a nonprofit watchdog group, does not believe the federal government should shift responsibility for food safety to private auditors.

“People confuse the role of audits,” she said. “People think it’s the same as a federal inspection but it’s not. It’s the government that has a public health mandate.”

Even if federal inspections are done once every five years, they represent a “threat” to companies that cut corners on food safety.

Private audits, Hitt added, are only as strict as the company being audited or its customer wants them to be. “If [a supplier] wants to get into McDonald’s, they have to bring a high-quality audit,” she said.

Most audits, however, are based on standard industry practices, not best practices, noted Jim Prevor, who writes the widely read Perishable Pundit blog. If all audits are conducted at the higher standard, “will it really be acceptable to flunk 80% of the nation’s facilities on these audits, especially if the operators will never be able to meet the new standards?” he wrote in a recent post.