On Tuesday, shares of organic grocery chain Whole Foods Market are sliding, down just over 2% in midday trading after the Food and Drug Administration (FDA) issued a warning letter citing serious violations of regulations for manufacturing, packaging, and storing food at a Massachusetts plant.

During many inspections in February, the FDA found listeria and other severe food-safety violations. The agency said it saw ready-to-eat pesto pasta and ready-to-eat mushroom quesadillas being mixed and prepared in an area of an assembly room where condensate from ceiling joints was dripping onto surfaces below.

An employee was observed spraying ammonium sanitizer near an open colander of salad, while another worker’s “upper sleeves were frequently touching” leafy greens that were being packaged. The FDA also saw one employee packing quinoa cakes without washing their hands or changing gloves.

"The FDA has serious concerns that our investigators found your firm operating under these conditions," the agency wrote in the letter, which was dated June 8. The FDA gave Whole Foods 15 working days to provide specifics on a plan to address the food-safety concerns.

The plant, which is based in Everett, Massachusetts, supplies prepared foods and other products to dozens of Whole Foods stores across the Northeast.

Currently, Whole Foods Market holds a #4 (Sell) on the Zacks Rank.

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