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Korean Findings Are Still Pending
The Japanese team working on a partial repeat of the NTP RF–animal cancer study has reported seeing no “reproducible” effects on cancer or genotoxicity in RF-exposed male rats.
The project —nicknamed NTP Lite— is a scaled-down version of the $30+ million project carried out by the U.S. National Toxicology Program which found “clear evidence” that RF radiation can cause cancer in rats. The NTP final report was released in 2018.
The Japanese results were published in the journal Toxicological Sciences yesterday, January 12. The paper is open access.
“This study performed in Japan, jointly planned and executed by Japan and Korea, provides strong evidence that long-term exposure to 900 MHz RF-EMFs did not produce reproducible carcinogenic or genotoxic effects in male rats,” states Katsumi Imaida of Japan’s Kagawa University, the leader of the Japanese study group.
“No statistically significant increases in the incidences of neoplastic or non-neoplastic lesions were found in any major organ, including the brain, heart, and adrenal glands. Genotoxicity assays revealed no evidence of DNA damage or chromosomal aberrations in RF-exposed rats,” according to the Japanese abstract.
The results of the parallel Korean experiment have not yet been released. The original plan was to combine the Japanese and Korean data to achieve greater statistical reliability. The leader of the Korean arm of the project is Young Hwan Ahn of Ajou University School of Medicine.
NTP Lite is years behind schedule. Work on the project began in 2018 and the RF exposures were scheduled to be completed over three years ago. Since then some partial reports have dribbled out (more here, here and here), leading some observers to suggest that the project would be unable to resolve the RF–cancer question.
For example, Microwave News was told last year that a group of animals were to be exposed to RF at 6 W/Kg in the Japanese experiment, but that part of the protocol was quietly abandoned. The new paper does not mention the 6 W/Kg animals, which were designed to serve as positive controls.
Joel Moskowitz of the UC Berkeley School of Public Health, who runs the Electromagnetic Radiation Safety website, offered the following comment based on a preliminary reading of the new Japanese study: “A null result in the Japanese NTP Lite study should not be considered a refutation, because it is underpowered to see relatively low‑incidence tumors.”
Here is the abstract of the published paper:
This is a developing story and will be updated as further details emerge.