FDA May Investigate DNA Contamination in COVID Shots

The U.S. Food and Drug Administration (FDA) is considering investigating potential DNA contamination in mRNA COVID-19 shots. Tracy Beth Hoeg, MD, senior adviser to FDA commissioner Marty Makary, MD, MPH, confirmed that the investigation is “something that’s being discussed.”¹

Retsef Levi, PhD, chair of the U.S. Centers for Disease and Prevention’s (CDC) COVID-19 immunization workgroup, has presented data suggesting the mRNA platform used in the COVID shots isn’t working the way the public was told that it would. “We have a range of things on the mRNA platforms that really suggest that it doesn’t work as intended,” Dr. Levi said, citing evidence of widespread spike protein and mRNA distribution throughout the body, as well as “DNA contamination.”¹

Last year, Florida Surgeon General Joseph Ladapo, MD, PhD, formally urged the FDA to investigate possible DNA contamination in Pfizer/BioNTech’s Comirnaty and Moderna/NIAID’s Spikevax COVID shots. Dr. Ladapo warned that residual DNA fragments encapsulated in lipid nanoparticles could integrate into human cells, potentially raising cancer risk.²

Similarly, Phillip Buckhaults, PhD, professor of cancer molecular genetics at the University of South Carolina, publicly cautioned that mRNA COVID shots were contaminated with plasmid DNA used during manufacturing. “We should insist that the USFDA force Pfizer to get the DNA out of the booster and all future mRNA-based vaccines,” Dr. Buckhaults wrote in a 2023 university publication. He added that each shot may contain “about 200 billion pieces of plasmid DNA encapsulated in the lipid nanoparticle,” warning of possible autoimmune reactions, cardiac events, or future cancer risks depending on DNA integration sites. ^{2 3}

Lab Analysis Finds Detectable Plasmid DNA in All Examined mRNA Shot Vials

In 2023, Canadian regulators confirmed that Pfizer’s vaccine contained a previously undisclosed DNA sequence, according to The Epoch Times. Former Johnson & Johnson scientist David Wiseman and genomic researcher Kevin McKernan, founder of Medical Genomics, both raised alarms about the potential effects of residual plasmid DNA, which has been used historically in drug manufacturing. “That DNA could integrate into the human genome and create autoimmunity problems,” McKernan said.¹

At the time, an FDA spokesperson maintained that “no safety concerns related to the sequence of, or amount of, residual DNA have been identified.” However, McKernan and other researchers later found residual DNA levels in certain vaccine batches exceeding FDA regulatory limits, according to a peer-reviewed study published Sept. 6, 2025 In the journal Autoimmunity.¹

The study, authored by McKernan and other scientists, reported: “Residual DNA was detected in all 32 vaccine vials surveyed. Multiple vials from the same lots produced very similar loads for all targets showing assay reliability, reproducibility, and consistency within the lots.”

The authors concluded that their findings “extend existing concerns about vaccine safety and call into question the relevance of guidelines conceived before the introduction of efficient transfection using lipid nanoparticles.”⁴

Representatives from both Moderna and Pfizer defended their manufacturing and testing processes, saying that all vaccine batches are screened for residual DNA using validated, industry-standard methods. Moderna’s Darin Edwards said some independent testing cited by critics was flawed, while a Pfizer official added that the company’s internal assays are designed specifically to measure residual DNA—not RNA—to ensure accuracy. However, independent researchers have pointed out that the companies’ testing methods may not detect every type of DNA fragment, especially those enclosed within the lipid nanoparticles used to deliver the mRNA—leaving some uncertainty about how much DNA remains in the final product and what effects it might have.¹

CDC Panelists Question Why COVID Shots Remain on the Market

During the Sept. 19, 2025 meeting of the CDC’s Advisory Committee on Immunization Practices (ACIP), panel member Kirk Milhoan, MD, PhD expressed alarm over what he called a “lack of pharmacological rigor in dosing” and the evidence of potential contamination. “Why is this not pulled off [the market] like any other biologic or medicine that is found to have contamination?” Dr. Milhoan asked.¹

Dr. Hoeg responded that while some manufacturer data remain proprietary, information shared with the FDA was “within regulatory limits.” She added, “At the FDA, we take the public’s safety and the safety of these products incredibly seriously. … This is not something that is being ignored.”¹

Several panel members also voiced concern that current vaccine information statements do not adequately inform consumers of potential risks, urging the CDC to require that healthcare providers discuss both benefits and risks in more balanced terms. They proposed that vaccine statements include acknowledgment that “prolonged and persistent exposure” to the ingredients in the mRNA biologic, such as spike, mRNA, and nano-lipid particles, has been associated with post-vaccine injuries and potentially other side effects and that there is only partial understanding of the biological mechanisms involved in adverse events.¹

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