WASHINGTON – The source of salad mix linked to an outbreak of cyclosporiasis in Iowa and Nebraska has been traced to Taylor Farms de Mexico, S. de R.L. de C.V., a business unit of Taylor Farms, Salinas, Calif., according to the Food and Drug Administration. The F.D.A. said the source of additional outbreaks of cyclosporiasis in other states has yet to be determined.

The Iowa Department of Inspections and Appeals and the Nebraska Department of Health and Human Services announced that they believe the contaminated salad is no longer in the food supply in those states. The last date that someone reportedly became ill with cycloporiasis in Iowa was July 1, and in Nebraska on July 2. The typical shelf life for a salad mix is up to 14 days.

As of Aug. 1, the Centers for Disease Control and Prevention had been notified about more than 400 cases of Cyclospora infection. States where the source of the infection has not been identified include Arkansas, Connecticut, Florida, Georgia, Illinois, Kansas, Louisiana, Minnesota, Missouri, New Jersey, New York, Ohio, Texas and Wisconsin.

The F.D.A. said Taylor Farms de Mexico is cooperating with the investigation. The F.D.A. and the company are conducting an environmental assessment of the processing facility in Mexico to try to learn the probable cause of the outbreak and identify preventive controls to put in place to try and prevent a recurrence. The most recent F.D.A. inspection of the facility, which took place in 2011, found no notable issues, according to the F.D.A.

As a result of the investigation, the F.D.A. said it is increasing its surveillance efforts on green leafy products exported to the United States from Mexico.

“We care deeply about the health and welfare of our customers and are absolutely committed to ensuring every salad we produce is great tasting, healthy, wholesome and, most importantly, safe,” said Taylor Farms in a statement. “This is why Taylor Farms de Mexico assesses and tests all water sources, raw product fields; every lot, every day for any risk to our valued customers’ products. We are redoubling and enhancing our testing and scrutiny in these areas to further assure food safety.”

Taylor Farms de Mexico exclusively provides fresh cut and value-added produce to the food service industry, according to the company. During the month of June the company said it produced and distributed approximately 48 million servings of salads to restaurants in the Midwest and Eastern U.S.