A rodent nest that is home to numerous critters. Birds defecating on stored food. Rodent waste. These images are among the observations the U.S. Food and Drug Administration (FDA) detected last year at a Pennsylvania food warehouse.

The observations, referenced last month in a warning letter, caught the attention of Sen. Charles Schumer. Schumer (D-New York) on Monday urged FDA to exert more oversight and enforcement over food warehouses that are infested with rats and otherwise make the average stomach churn.

Last year alone, FDA fired off warning letters to around 90 food facilities that had insanitary conditions, Schumer’s office said in a press release. Schumer cited a number of revolting conditions that FDA inspectors had observed, included dead mice and rats at a facility that made cookies, and insects at a rice production facility.

Schumer acknowledged the four-year-old Food Safety Modernization Act (FSMA) granted FDA more oversight over food facilities, but he said the agency should do more to crack down on insanitary facilities.

In a letter to FDA, Schumer pressed the agency to classify as “high risk" every facility that is the subject of a warning letter and increase the number of inspections for such plants. He also said FDA should make it easier for consumers to learn about food-safety violations, and increase the penalties for facilities that have a record of repeated food-safety violations.

“Reports of the filthy conditions at some of these warehouses sound like a page straight out of Upton Sinclair’s ‘The Jungle,’" the senator said in a statement. “It’s clear that more must be done to ensure cannolis, Chinese food, pizza dough and other delicious food are the only items on the menu! The FDA should immediately implement a three-pronged plan that would boost the number of inspections, create a public, searchable database about violations and increase the fines to improve conditions and deter future violations."

Noah Bartolucci, an FDA spokesman, said the agency will respond to Schumer upon receipt of his letter. He noted FDA is working on implementation of FSMA--the nation's most comprehensive reform of U.S. food-safety laws in generations--and has proposed rules governing human food preventative controls and produce-safety standards. The rules are aimed to identify and correct potential food-safety hazards as well as prevent microbiological contamination of vegetables and other produce.

"These and other preventive measures being implemented under FSMA will help to manage risks to our food system," Bartolucci said in an emailed statement.

Some conspicious and despicable food-safety violations were referenced by Schumer in a Dec. 9, 2014 warning letter that FDA recently sent to Brooklyn, New York-based New Yung Wah Trading Company. FDA told the company that it had observed a number of odious conditions at its facility in McKees Rocks, Pennsylvania during an October 2014 inspection.  The observations included among other things the presence of a nest that harbored multiple rodents, dead critters, and birds landing and defecating on stored food.

Bartolucci said the company voluntarily destroyed the affected products at the facility before receiving the warning letter.

New Yung Wah Trading Company did not immediately return a call from Food Product Design seeking comment. But it told FDA in a written response to FDA’s observations that it “aggressively addressed the deviations", according to the warning letter. FDA wasn’t impressed. Anne Johnson, FDA’s Acting District Director with the Philadelphia District, said in the warning letter the company failed to provide documentation to show that it made the corrections.

The company was given 15 days from receipt of the warning letter to notify FDA of its plan to correct the mess.