Editor’s note: The following is cited from a U.S. government website which provides some information about cell phone radio frequency radiation and its potentially harmful effect on cancer risk. Studies were conducted by National Toxicology Program which is a U.S. agency that is intended to have a judgement as to whether a substance is a cancer causing agent.
Keep in mind that the research/review is sponsored by the government and its conclusions reflect the opinion of the government. Regardless of how harmful the cell phone radio frequency radiation is to humans, it seems apparent that the radiation does cause harm, particularly when cell phones are used heavily or improperly for a long term.
編者註：以下摘自美國政府網站，該網站提供了有關手機射頻輻射及其對癌症風險的潛在有害影響的一些信息。 由美國國家毒理學計劃（National Toxicology Program）進行了研究，該計劃旨在判斷某種物質是否為致癌因子。 請記住，這項研究/評論是由政府贊助的，其結論可能會受到行業的影響。 不管手機射頻輻射對人體有多有害，似乎輻射確實會造成傷害，特別是當長期大量使用或不正確使用手機時。
Cell phones are currently used by 95% of American adults. The U.S. Food and Drug Administration (FDA) nominated radio frequency radiation (RFR) used by cell phones for an NTP study because of widespread public use of cell phones and limited knowledge about potential health effects from long-term exposure.
NTP Studies & Findings
NTP conducted two-year toxicology studies in rats and mice to help clarify potential health hazards, including cancer risk, from exposure to RFR like that used in 2G and 3G cell phones which operate within a range of frequencies from about 700–2700 megahertz (MHz). These were published as Technical Reports in November 2018.
What did the studies find?
NTP uses a standard scale (graphic of NTP’s Level of Evidence Rating System for Cancer Studies) to determine the strength of the evidence for an association between the exposure and findings in the tissues or organs studied. The scale ranges from the highest rating of “clear evidence,” followed by “some evidence,” then “equivocal evidence,” and finally “no evidence.” Different organs or tissues can have different conclusions.
The NTP studies found that high exposure to RFR (900 MHz) used by cell phones was associated with:
- Clear evidence of an association with tumors in the hearts of male rats. The tumors were malignant schwannomas.
- Some evidence of an association with tumors in the brains of male rats. The tumors were malignant gliomas.
- Some evidence of an association with tumors in the adrenal glands of male rats. The tumors were benign, malignant, or complex combined pheochromocytoma.
It was unclear if tumors observed in the studies were caused by exposure to RFR in female rats (900 MHz) and male and female mice (1900MHz).
As a follow-up, NTP published an article in October 2019 that evaluated DNA damage in three regions of the brain, the liver, and in blood cells in rats and mice that were removed at an earlier timepoint from the ongoing 2-year toxicology study. DNA damage, if not repaired, can potentially lead to tumors. This work was also included in NTP’s published Technical Reports, but this study includes analyses of the data in the supporting information not included in the Technical Reports.
NTP scientists found that RFR exposure was associated with an increase in DNA damage. Specifically, they found RFR exposure was linked with significant increases in DNA damage in:
- the frontal cortex of the brain in male mice,
- the blood cells of female mice, and
- the hippocampus of male rats.
There are many factors that influence whether damaged DNA will lead to tumors. NTP plans to conduct additional studies to learn more about how RFR might cause DNA damage. Please see the FAQs below for more information about the specific studies and NTP’s cell phone RFR program.