FDA Finds Black Mold and Insect Infestation at Chinese Drug Ingredient Plants

By the Editorial Team · Thursday, October 22, 2026

The FDA uncovered severe contamination and regulatory breaches at two Chinese factories producing active ingredients for compounded GLP-1 weight-loss drugs used in the U.S., including mold, insect infestations, and fraudulent quality assurances. These violations have led to import restrictions and raised concerns about the safety of compounded medications that bypass standard FDA approval processes amid growing U.S. demand.

U.S. Food and Drug Administration inspectors recently documented serious violations at two Chinese factories producing active pharmaceutical ingredients for compounded GLP-1 drugs, which are widely used in weight-loss treatments in the United States. The inspections uncovered black mold on equipment, extensive insect infestations, and significant contamination on factory floors, raising concerns about the safety and quality of these products.

The investigations targeted Chengdu Shengnuo Biopharm Co., a subsidiary of Chengdu Shengnuo Biotec Co., and Nanjing Chengong Pharmaceutical Co., both of which manufacture semaglutide and tirzepatide—the active ingredients in popular drugs from Novo Nordisk and Eli Lilly & Co. These ingredients are used in compounded versions of the medications that have not been approved by regulatory authorities or evaluated for safety and efficacy.

At the Chengdu Shengnuo facility, inspectors found black mold growing on manufacturing equipment alongside “gross contamination” on the plant floors. In addition to these unsanitary conditions, there was notable insect activity within the ceilings. Inspectors also observed employees attempting to conceal documents and pouring out product samples in an effort to avoid detection.

The inspection at Nanjing Chengong revealed that workers had been purchasing active ingredients manufactured by third-party factories and then fraudulently applying Nanjing Chengong’s quality assurance seal without conducting proper safety reviews or testing. This practice violates FDA requirements, which mandate that producers verify ingredient safety and maintain documentation accessible for inspection.

Following the inspections, the FDA placed both companies on an import-alert list, potentially barring their products from entering the U.S. market. While brand-name and generic pharmaceuticals undergo rigorous FDA evaluation, compounded drugs are not subject to the same premarket approval process. The FDA conducts spot inspections of suppliers to compounding pharmacies, which are expected to source ingredients only from registered and compliant manufacturers.

Michael Rogers, a former associate commissioner for inspections and investigations at the FDA, characterized the violations as indicative of a “serious accident waiting to happen.” The incidents come amid increasing demand in the U.S. for compounded versions of semaglutide and tirzepatide, which saw shortages in 2022 and have driven growth in the compounding industry as an alternative supply source.

Chengdu Shengnuo acknowledged the FDA findings in a recent filing with Chinese regulators, stating it was actively implementing corrective measures to address the violations. Neither company responded to requests for comment on the inspection reports.

Most recently, Nanjing Chengong underwent an inspection in September 2023, and Chengdu Shengnuo was last inspected in March 2025, according to FDA records. The findings have heightened scrutiny over overseas suppliers of pharmaceutical ingredients, particularly those servicing facilities that produce compounded medications, which fill gaps in treatment options but may carry unverified risks.

This article was reported by synthesizing coverage from multiple independent news outlets to present a balanced, unbiased account. Read about our editorial standards. Spotted an error? Let us know.