The U.S. Food and Drug Administration (FDA) has issued a letter to American supermarket chain Whole Foods regarding what the agency refers to as "serious violations" in proper food preparation it discovered after inspecting the company's Massachusetts facility.

According to the FDA, inspectors found several instances of unsanitary practices such as allowing Whole Foods products, including couscous, mushroom quesadillas, egg salad and pesto pasta, to be exposed to "condensate" from a condenser fan, a doorway and ceiling joints.

Agency officials also cited other violations on the part of Whole Foods such as failing to properly sanitize surfaces for food preparations, failing to provide water for hand washing in sinks and placing food near dirty dishes. Inspectors said the company also allowed one of its employees to spray ammonium-based sanitizer on several leafy greens meant for salads.

While Whole Foods has yet to comment on the recent food safety concerns, the FDA said it had received a response from the supermarket chain back in March. It informed the agency that it is taking such concerns seriously and that it will follow proper procedures to address problems.

Despite this, the FDA said it has yet to see some action from Whole Foods to show that they are really willing to correct the "serious concerns" that agency inspectors found recently.

"We do not consider your response acceptable because you failed to provide documentation for our review," the FDA said in its letter.

Previous Food Safety Concerns

Whole Foods has experienced its fair share of food safety risks in the past concerning their products. In October, the company was forced to recall its cheese and pasta products because of possible listeria contamination.

In March, the supermarket chain also had to pull out its raw milk blue cheese from stores because of a similar listeria risk.

The company's latest issue with food safety violations has caused its shares to drop by more than 2.5 percent on Tuesday, bringing its stock in the red for 2016.

Whole Foods has struggled in the past few years with its stock falling by more than 10 percent in 2014 as investors grew increasingly concerned about the company's slowing sales.

In 2015, company shares plummeted by close to 35 percent because of several food safety concerns as well as allegations that it had overcharged its customers and other health concerns.

Many consider Whole Foods as the company that helped popularized the consumption of organic food products. However, the supermarket chain has long since surrendered its lead in the natural market.