A ground-breaking peer-reviewed study by Dr. David J. Speicher, Dr. Jessica Rose, and Kevin McKernan, published in 2025, has exposed an alarming truth: Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines are contaminated with residual plasmid DNA at levels up to 627 times higher than international regulatory safety limits. Analyzing 32 vials across 16 unique lots, the study found billions to hundreds of billions of DNA fragments in every dose, with Pfizer vials also containing SV40 promoter-enhancer sequences, genetic elements linked to genomic integration and cancer risk. These findings, corroborated by at least 10 independent global reports, reveal a persistent and dangerous flaw in mRNA vaccine production that regulators have failed to address. As Nicolas Hulscher, MPH, argues, the overwhelming evidence of contamination demands the immediate withdrawal of these vaccines to protect public health from risks like insertional mutagenesis and oncogenesis. This discussion supports Hulscher's call, detailing the study's findings, their implications, and why halting these vaccines is a moral and scientific necessity.
The Study: A Damning Revelation
The Speicher et al. study, conducted with rigorous methodology, tested 32 vials of Pfizer and Moderna mRNA vaccines, including older monovalent and newer bivalent and XBB.1.5 formulations. Using fluorometry with RNase A digestion and qPCR, researchers found DNA contamination levels far exceeding the FDA and WHO's 10 ng per dose limit, established decades ago to prevent genomic harm. Key findings include:
Extreme Contamination Levels: Pfizer doses contained 371–1,548 ng of DNA per dose, 36–153 times over the limit. Moderna doses ranged from 1,130–6,280 ng, a staggering 112–627 times over. Every vial tested was contaminated, with no improvement in newer formulations.
SV40 Promoter-Enhancer in Pfizer: Found only in Pfizer vials, SV40 sequences ranged from 0.25–23.72 ng per dose. These elements are known for driving DNA into cell nuclei, potentially mutating genes or activating oncogenes, raising cancer risks.
Lipid Nanoparticle Delivery: DNA fragments, some up to 3.5 kb and carrying 100–160 billion copies per dose, were encapsulated in lipid nanoparticles (LNPs). LNPs bypass natural defences, delivering DNA directly into cells, something regulators never accounted for in safety limits.
Adverse Event Correlation: Pfizer lots with the highest DNA contamination correlated with extraordinarily high serious adverse event (SAE) reports in VAERS, with some lots linked to 50–95% serious outcomes, suggesting a direct link to harm.
These results confirm that mRNA vaccine contamination is not a relic of early production, but a persistent issue across all formulations, including those adapted for Omicron variants.
Regulatory Failure and Historical Context
The FDA and WHO set the 10 ng/dose DNA limit to prevent risks like insertional mutagenesis, where foreign DNA integrates into the human genome, potentially disrupting genes or triggering cancer. The SV40 promoter-enhancer, found only in Pfizer vials, is particularly alarming due to its history. In the 1950s and 1960s, polio vaccines contaminated with the full SV40 virus raised concerns about cancer in animals, though human studies were inconclusive. Unlike those cases, the mRNA vaccines contain only SV40's regulatory sequences, not the virus itself, but these sequences are potent enough to drive genomic integration, as noted in a 1999 study.
Regulators, including the FDA, Health Canada, and Australia's TGA, have downplayed the issue, claiming residual DNA is "inactive" and within limits. However, the Speicher study's fluorometry data, showing contamination up to 627 times over, debunks these claims. qPCR, used by regulators, underestimates DNA by missing smaller fragments, a methodological flaw the study exposes. The presence of LNPs, which deliver DNA directly into cells, further invalidates outdated safety thresholds designed for traditional vaccines. As Hulscher notes, regulators' failure to address this "categorically unacceptable" risk is a betrayal of public trust.
The Risks: Cancer, Mutagenesis, and Beyond
The study's findings raise serious concerns about long-term health risks. SV40 promoter-enhancer sequences, as McKernan's team highlights, can integrate foreign DNA into the genome, potentially activating oncogenes or disrupting tumour suppressor genes. A 2023 preprint by Rubio-Casillas et al. suggested mRNA vaccines' methylpseudouridine modifications may promote cancer proliferation, compounding the danger. The sheer volume of DNA fragments, 100–160 billion per dose, amplifies the likelihood of such events, especially when delivered via LNPs that evade cellular defences.
VAERS data, while not conclusive, shows a correlation between high-DNA lots and serious adverse events, including hospitalisations and deaths. Posts on X support this, pointing to real-world reports of cancers and autoimmune disorders post-vaccination. While correlation isn't causation, the study's evidence of contamination exceeding safety thresholds by orders of magnitude demands urgent investigation, not dismissal.
Why Withdrawal Is Necessary
Hulscher's call for market withdrawal is grounded in the precautionary principle: when risks outweigh benefits, action must be taken. The mRNA vaccines, initially hailed as life-saving, have faced scrutiny as real-world data shows waning efficacy against transmission and rising reports of adverse events. A 2022 Lancet study estimated vaccines saved 19.8 million lives globally, but Kennedy's Senate testimony in 2025 questioned such modelling, demanding raw data. With newer variants like XBB.1.5 showing reduced severity, the theoretical benefits of continued vaccination are diminishing, while the risks of DNA contamination grow clearer.
The persistence of contamination in bivalent and XBB.1.5 formulations proves manufacturers have not addressed the issue. Pfizer's claim, per AP News (2023), that SV40 sequences are "common practice" and safe is undermined by the study's data, which shows violations of regulatory limits. Moderna's silence and regulators' insistence on "no evidence of harm" ignore the lack of long-term studies on genomic integration. As Hulscher argues, every day these vaccines remain on the market risks further harm, particularly to vulnerable populations like children and pregnant women.
Countering the Critics
Critics, including FactCheck.org and Health Feedback, argue the DNA levels are negligible and lack a "biologically plausible mechanism" to cause harm. They cite experts like Dr. Paul Offit, who claims residual DNA is less dangerous than daily environmental exposures. However, these arguments fail to address the unique delivery mechanism of LNPs, which bypass natural barriers, and the specific risks of SV40 sequences, which even regulators acknowledge as potent. The dismissal of the Speicher study as a preprint ignores its peer-reviewed status and corroboration by 10 other global reports, as Hulscher notes. The critics' reliance on outdated testing methods, like qPCR, further weakens their case against the study's robust fluorometry data.
Conclusion
The Speicher et al. study is a call for accountability. The presence of billions of DNA fragments, SV40 sequences, and their delivery via LNPs in Pfizer and Moderna vaccines violates decades-old safety standards. The correlation with serious adverse events in VAERS underscores the urgency. Hulscher's demand for withdrawal is not anti-science but a defence of rigorous standards against corporate and regulatory complacency. Governments must halt these vaccines, conduct independent genomic safety studies, and hold manufacturers accountable. Citizens, as seen in posts on X, are increasingly vocal, demanding transparency over blind trust. Withdrawing these contaminated vaccines is the first step toward restoring trust and protecting lives from preventable harm.
https://jonfleetwood.substack.com/p/627-times-more-plasmid-dna-contamination
https://www.thefocalpoints.com/p/breaking-updated-pfizer-and-moderna