The $30 Million Government Study: What the NTP Found When It Tested Cell Phone Radiation on Rats
National Toxicology Program (NTP), 2016–2018 — U.S. Department of Health and Human Services
Institution: National Toxicology Program, U.S. Dept. of Health & Human Services
Duration: 10 years (2006–2016 exposure; 2018 final report)
Budget: ~$30 million
Findings: Clear evidence of carcinogenicity in male rats; some evidence in female rats and male mice
Why the NTP Study Matters
Before 2018, the question of whether cell phone radiation could cause cancer was largely unanswered by rigorous experimental evidence. Epidemiological studies had associations; animal studies existed but were smaller and less controlled. The NTP study was designed specifically to answer the question at scale, with the resources and duration necessary to detect low-incidence effects that shorter studies would miss.
It is the most controlled, best-resourced animal study of RF-EMF carcinogenicity ever conducted. Its conclusions cannot be dismissed as underpowered or poorly designed.
What the Study Found
The Ramazzini Replication
Within months of the NTP publication, the Ramazzini Institute in Italy independently replicated the schwannoma finding — at exposure levels far lower than the NTP used, and using whole-body exposure (simulating environmental tower exposure rather than the NTP’s near-field device exposure). Two independent labs, different countries, different exposure methods, same tumor type. This convergence is scientifically significant. Read the Ramazzini replication study →
The Aires Research Connection
The NTP finding establishes that RF-EMF at levels relevant to current device use produces biological effects that culminate in tumor formation in an organism with similar biological architecture to humans. This is the macro-level outcome. The IFRAN rat studies in the Aires research corpus used a similar biological model (Wistar rats, RF-EMF exposure) to test whether structural field modulation changes the biological response — measuring oxidative stress markers, hormonal endpoints, and tissue health parameters. The NTP gives context to what the Aires IFRAN studies are measuring against. Explore the Aires research corpus →
The U.S. government spent $30 million to answer this question. The answer was clear evidence.
The NTP result is the most rigorous animal evidence for RF-EMF carcinogenicity in existence.
Shop Aires Products →Frequently Asked Questions
What did the NTP study find about cell phone radiation and cancer?
The NTP study found clear evidence of malignant schwannomas of the heart in male rats exposed to 900 MHz RF-EMF, and some evidence of malignant gliomas in male rats. Both findings were statistically significant compared to unexposed controls. These are the highest-quality animal experimental results for RF-EMF carcinogenicity available.
What is a schwannoma and why does finding them in rats matter?
Schwannomas are tumors of Schwann cells — the cells that form the myelin sheath around nerve fibers. In humans, acoustic neuromas (vestibular schwannomas) have been associated with cell phone use in multiple epidemiological studies. The NTP finding of cardiac schwannomas in rats exposed to RF-EMF at device-relevant levels strengthens the biological plausibility of the human association.
Was the NTP study designed to reflect real cell phone use?
The NTP study used 900 MHz RF-EMF (matching 2G/3G frequencies) at SAR values of 1.5–6 W/kg. While the SAR levels used were higher than typical device exposure averaged over the body, the near-field exposure conditions were designed to model device-relevant scenarios. The Ramazzini study, using far lower whole-body exposure levels, independently replicated the schwannoma finding.
Has the NTP result changed official EMF safety guidelines?
Not yet, as of 2026. The NTP published its findings and recommended that the IARC reconsider its current Group 2B classification of RF-EMF. Multiple independent scientists have called for regulatory review based on the NTP and Ramazzini findings. The FCC and ICNIRP guidelines remain based on thermal thresholds established in the 1990s and have not been updated to reflect the NTP evidence.
The EMF Landmark Research Series
- This post: NTP 2018 — Government Cancer Study
- Ramazzini 2018 — Independent Replication at Lower Exposure
- Hardell 2013 — Long-Term Brain Tumor Epidemiology
- Interphone — WHO 13-Country Brain Tumor Study
- IARC 2011 — WHO Group 2B Classification
- Salford 2003 — Blood-Brain Barrier
- Volkow 2011 — JAMA Brain Metabolism
- REFLEX Project — EU DNA Damage Study
- Lai & Singh 1995 — DNA Strand Breaks
- Yakymenko 2016 — 93% Oxidative Stress Rate
- De Iuliis 2009 — Human Sperm DNA Damage
- Yu 2021 — Sperm Quality Meta-Analysis
- Levitt 2022 — Wildlife & Ecosystem Effects
- Pall 2016 — Voltage-Gated Calcium Channels
- Panagopoulos 2021 — Ion Channel Mechanism
- Betzalel 2017 — 5G & Skin as Antenna
- BioInitiative — 1,800 Studies Reviewed
- Johansson 2006 — EHS Biomarkers