Documents reviewed by the Springfield News-Sun show Dole’s Springfield facility was not cited for any significant health violations in the latest inspection since the company voluntarily closed the plant in 2016.

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Dole voluntarily recalled pre-packaged salads and closed the Springfield plant for four months in 2016 after a Food and Drug Administration and Centers for Disease Control and Prevention investigation linked the site to a suspected outbreak of listeria. The News-Sun filed a Freedom of Information Act request for all inspection records from the FDA since the outbreak to review whether any noteable violations remain.

Officials from the company did not respond to requests for comment, and the Springfield facility has long since reopened.

Information from the Centers for Disease Control and Prevention shows the outbreak affected at least 19 people in the U.S., including one person from Michigan who died. The Public Health Agency of Canada has also reported 14 cases in five provinces, including three deaths, although it hasn’t been determined if listeria contributed to the cause of those deaths.

About 1,600 illnesses and 260 deaths due to listeriosis occur annually in the U.S., according to the CDC. Listeria is a food-borne bacteria typically found in raw vegetables and meats, as well as some soft cheeses.

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Peter Cassell, a spokesman for the FDA, didn’t elaborate on the agency’s response to Dole’s Springfield site. But he said in general the agency looks for ways to prevent future outbreaks.

“An FDA post-response team looks at all aspects and factors of the outbreak, from ingredient sourcing to production and distribution,” Cassell said. “Team members work to identify the source of an outbreak and how the contamination could be prevented in the future. Their work may lead to new research on how contamination can occur, or it may lead to outreach to industry and other food safety agency partners on new ways to prevent future outbreaks.”

Documents provided by the FDA show the agency’s inspectors did issue a finding in 2016 during the outbreak to the firm for “failure to perform microbial testing where necessary to identify sanitation failures and possible food contamination.”

By the end of that inspection, the company also voluntarily recalled all products manufactured at the facility. The company also shut down operations while it conducted an investigation into the source of the listeria contamination, the inspection reports showed.

The latest inspection report provided by the FDA, conducted in January 2017, showed six samples were collected during the inspection for listeria analysis but did not recover the pathogen in any of the samples. Inspectors for the FDA also did not issue any significant findings in the most recent inspection, which was dated from Jan. 23 to Feb. 2 last year.

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The inspection report provided by the FDA redacted significant portions of the report that explain the company’s procedures for sampling and testing for pathogens like listeria and salmonella.

Swab versus finished product testing

The FDA’s inspection in January last year may not have resulted in significant findings but two items in that report stood out, said Michael Doyle, who recently retired as Regents Professor of Food Microbiology at the Center for Food Safety University of Georgia.

Company officials told inspectors from the FDA the company does not test finished products for listeria, but instead swabs various locations throughout the facility to identify potential pathogens. That’s fairly typical, particularly in the produce processing industry because produce is inherently contaminated with bacteria at low levels, Doyle said.

“They don’t want to do finished product testing because if you test enough you’re going to find something,” Doyle said. “If they find it that would lead to a recall and that could be a large amount of product.”

Inspectors also recommend the company begin swabbing for listeria in a section of the facility that was redacted in the file. Officials from the company responded in the report by pointing out that “some elements of the firm’s environmental monitoring program go above and beyond certain recommendations in the FDA draft guidance document.”

Company officials also said the firm would have ongoing discussions about that recommendation, but it’s unclear whether that recommendation was ever followed.

It’s difficult to know how important that item is because the section in question was redacted from the report, said Ben Chapman, a food safety specialist and associate professor in the Department of Agricultural and Human Sciences at North Carolina State University. If the section was in an area near food production that might be noteable. But it might not be a concern if it was in a section of the facility where there was no possibility of coming in contact with the product.

Testing various parts of a facility can be an effective method to detect pathogens like listeria in a manufacturing facility, said Bill Marler, a Seattle attorney specializing in food safety cases. Marler represented the family of Kiki Christofield, an Ohio woman whose family filed a civil lawsuit against Dole related to the outbreak. That case has since been settled.

Still, Marler said end product testing is preferable if possible because it allows companies to determine whether their food safety plans are effective.

“Testing, especially end product testing is not going to give you complete assurance that the product is without pathogens,” Marler said.

That’s in part because companies are only doing a random sample of their products. But he said it can allow companies to find defective products and work their way back to determine how that product may have been contaminated. The FDA does not mandate end product testing, he said.

“Testing food contact surfaces, testing drains, finding out if you’ve got listeria in your facility is the next best thing as a way to protect your consumers and to protect yourself,” Marler said of food manufacturers.

Doyle pointed out harmful bacteria can be killed in products like meats if cooked properly. But items like bagged salads are typically eaten without cooking. It is true that the industry sells millions of bagged salads a year and the percentage of outbreaks is very small.

“The fresh produce industry is likely to be more impacted more than others because people eat a lot of fresh produce and the industry does not have fully effective ways to kill the harmful bacteria,” Doyle said. “If you’re eating bagged salads, the treatments that are applied help but they don’t eliminate the harmful microbes you can find on produce.”

Improved technology

Moving forward, companies involved in the food production industry as a whole are more likely to be linked to foodbourne outbreaks across the U.S. as testing procedures have improved, Doyle said.

In Dole’s case in Springfield, the CDC used a technique called whole genome sequencing to link the outbreak to the local facility. In that process, DNA fingerprints were pulled from samples of listeria from ill patients. Public health labs across the U.S. upload the DNA fingerprints to Pulsenet, a network used to monitor food poisoning cases.

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The CDC can then review data to see if something unusual or unexpected is happening, indicating a possible outbreak. Those kinds of advanced laboratory techniques weren’t available in recent decades.

Federal investigators became aware of the outbreak using PulseNet. They eventually tied the outbreak to 22 packaged salad products under the Dole brand as well as several store brands for Kroger, Aldi, Meijer and Wal-Mart. Dole stopped production and voluntarily recalled the affected products.

Documents filed last year with the U.S. Securities and Exchange Commission showed the voluntary recall and four-month shutdown was costly for the company. The recall and shutdown of Dole’s Springfield plant cost the company more than $25 million in 2016.

In that same filing, an initial public offering for Dole Food Company Inc., the company said it had been served with a subpoena in April 2016 from the U.S. Department of Justice seeking information for an investigation of the listeria outbreak at the Springfield site. However, the DOJ did not return calls seeking an update and no further details of that case were available.

“With the whole genome sequencing approach that the FDA and state health departments are now taking to detect outbreaks we’re probably going to see the the dots connected identifying outbreaks,” Doyle said. “It’s not necessarily because the companies are not as good as they used to be in terms of addressing food safety. It’s that the surveillance system is getting much better.”

Expansion possible

Dole has more than 700 employees at its processing plant in Springfield, which was built in 1998 and packages and distributes salad found in grocery stores across the country.

An affiliate of Dole purchased a nearly $550,000, 28-acre property near its plant along Titus Road last year. Local officials said the company needed the property in case of future expansion. The company is one of the most recognized brands for fresh fruit in the U.S. with revenue of about $4.51 billion in fiscal year 2016, according to documents the company filed with the SEC.

The company’s size and brand recognition make it more likely the business will be better prepared to weather any negative publicity related to the outbreak, Marler said. He pointed to companies like the Blue Bell Ice Cream company, which was responsible for a listeriosis outbreak that impacted about 10 people over several states in a five-year period from 2010 to 2015. That company took an economic hit, but has since recovered.

Companies like Dole often have insurance to cover the bulk of legal fees, Marler said. The real cost is in lost sales and costs associated with recalls.

“If you’re a company like a Dole or a Conagra you can weather that and frankly even weather an FDA fine if you have a commitment to fix the problem,” Marler said. “Many of these outbreaks are survivable but it takes enough resources to fix the problem and hopefully not repeat it again.”