An analysis of fresh sprouts and the companies that grow them has revealed relatively low numbers in terms of some foodborne pathogens — but also showed low compliance rates in terms of safety measures.

Out of 825 samples of seeds, water and finished sprouts tested, officials found Salmonella or Listeria contamination in only 14. None of the samples were positive for E. coli, but only finished sprouts and water were tested for that pathogen, not seeds, according to the Food and Drug Administration.

The 14 positive samples came from eight of the 94 growing operations included in the project, and 10 of the positives came from just four growers. FDA collected the samples from February 2014 through September 2015. Of the 825 samples, 608 came from growing operations, 101 from distributors and 116 from retailers across 37 states, Puerto Rico and Washington D.C.

In a report released Friday, the FDA detailed the procedures used and resulting data generated during the special “sampling assignment” that began in 2014 and was planned to last two years.

“About one year into the assignment, the FDA decided to stop its collection and testing at 825 samples because it had already collected samples on more than one occasion from many of the sprouting operations known to the agency and its state partners,” according to the report.

The FDA designed its sampling plan such that if contamination of one percent or greater was present in the commodity, the agency would detect it, according to the report.

The agency targeted fresh sprouts for the sampling program because they have been the source of many foodborne illness outbreaks in recent years.

“Sprouts are especially vulnerable to pathogens given the warm, moist and nutrient-rich conditions needed to grow them,” according to the FDA report.

“From 1996 to July 2016, there were 46 reported outbreaks of foodborne illness in the United States linked to sprouts. These outbreaks accounted for 2,474 illnesses, 187 hospitalizations, and three deaths.”

The FDA tested 14 different varieties of fresh sprouts during the project. The most frequently collected sprouts and the percentages of the total samples were mung bean at 36 percent, alfalfa at 21 percent, clover at 10.4 percent, and soybean at 10.4 percent.

Other sprout varieties collected during the sampling project include adzuki bean, broccoli, kale, mustard seed, onion, pea, radish, snow pea, sunflower, and wheat. In addition, 5 percent of the samples collected were described as “mixes,” meaning they contained two or more varieties.

The FDA estimates that about 55 million pounds of fresh sprouts are produced annually in the United States. The growing operations included in the special sampling project ranged in production from 25 pounds per week to 280,000 pounds per week.

In the sampling project, the agency was specifically looking for E. coli, Salmonella and Listeria monocytogenes bacteria.

During the project, FDA identified an ongoing Listeria monocytogenes outbreak, that killed two people. The implicated grower stopped production and recalled product. The business ultimately closed down.

“The FDA worked with the firms that owned or released affected sprouts to conduct voluntary recalls or to have their consignees destroy affected product, and then followed up with inspections. The agency also referred its findings to state authorities in two cases,” according to the report.

Other specific findings from the sampling project include:

  • Less than half of the sprouting operations bought seeds from a supplier who obtained them from growers who followed Good Agricultural Practices (GAPs);
  • One in 10 sprouting operations did not maintain “lot identity” for their seeds, which is used for traceability during recalls;
  • More than one in five sprouting operations did not visually examine the seeds or beans used for sprouting to check for signs of rodent intrusion, which is a key vector for pathogens;
  • Less than half of the sprouting operations had a written seed treatment program to reduce microorganisms;
  • Less than half of the sprouting operations conducted microbiological testing of water sources used for sprout irrigation;
  • Only 27 percent of sprouting operations collected a unique sample of spent water from each production batch of sprouts, which is required by federal law;
  • Only 38 percent of sprouting operations had a written sampling plan for spent water;
  • Virtually half — 49 percent — of sprouting operations did not have a corrective plan action for when a pathogen is detected in spent water;
  • Only 17 percent of the operations test for Listeria species or Listeria monocytogenes, as now required by the Produce Safety Rule of the Food Safety Modernization Act; and
  • Only 38 percent of the operations conduct environmental monitoring for pathogens in their facilities.

Moving forward
The FDA will continue to study microbial contamination of sprouts and how best to reduce it, according to the report.

Going forward, the FDA intends to inspect sprouting operations to ensure they are complying, as applicable, with the Produce Safety Rule, which includes new requirements for sprouts growers.

The agency has no plans to conduct additional large-scale sampling of sprouts at this time but may sample the commodity in accordance with its longstanding approach to food sampling, which centers on, but is not limited to, the following criteria:

A firm has a previous history of unmitigated microbial contamination in the environment (e.g., human illness, recalled or seized product, previous inspectional history, or environmental pathogens without proper corrective actions by the facility), or

Inspectional observations that warrant collection of samples for microbiological analyses.

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