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Your Environment. Your Health.

Cell Phone Radio Frequency Radiation


mobile phone

Cell Phones

Cell phones are currently used by 95% of American adults. NIEHS and other scientific organizations are actively studying the potential health effects of radio frequency radiation used in cell phones.

Fact Sheets

Cell Phone Radiofrequency Radiation Studies

What Is NIEHS Doing?

The National Toxicology Program (NTP), headquartered at NIEHS, has conducted toxicology studies in rats and mice to help clarify potential health hazards, including cancer risk, from exposure to radio frequency radiation like that used in 2G and 3G cell phones.

What did the studies find?

The NTP studies found that high exposure to RFR used by cell phones resulted in:

  • 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.

For female rats, and male and female mice, it was unclear if tumors observed in the studies were associated with RFR used by cell phones. This is also known as equivocal evidence.

The final conclusions represent the consensus between NTP and a panel of external scientific experts who thoroughly reviewed the NTP draft technical reports at a public meeting in March 2018.

The results are based on NTP’s four categories of evidence that a substance may cause cancer: clear evidence (highest), some evidence, equivocal evidence, no evidence (lowest).

Further Reading

Stories from the Environmental Factor (NIEHS newsletter)

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