The issue of cell phones and T cancer is in the news again since the National Toxicology Program (NTP) study has released its results. Keeping track of the NTP results can be difficult. In 2016, they released the partial findings of their study (Report of Partial Findings 2016), which showed an association between cell phones and two types of cancer (cardiac schwannomas and brain gliomas). The full data was released in February 2018 (Wyde et al. 2018), and while the cardiac schwannoma association remained statistically significant, the brain glioma association was seen as more equivocal. Then in March, as showing “some evidence.” (These reports are all online at the NTP website at ntp.niehs.nih.gov.)
Keeping track of this evolving evidence base can be confusing, and the NTP will issue a final report sometime this fall. But it’s worth examining why different people can come to such different conclusions about findings. the study’s findings.
The NTP study was designed to expose rats and mice to different levels of radio frequency radiation (RFR). One group was a control group and three other groups were exposed to 1.5W/kg, 3W/kg, and 6W/kg of RFR. Researchers also tested two forms of sig- the NTP study results went through peer review where an eleven-member panel reviewed and voted on whether to accept or modify the study’s recommendations. The peer review panel (Actions from Peer Review 2018) voted to label the cell phone cardiac schwannoma association as demonstrating “clear evidence” of carcinogenicity and the glioma association nal modulation, reflecting two major access technologies employed by cellular telephones: Code Division Multiple Access (CDMA) and Global System for Mobiles (GSM). Both technologies transmit data in the form of modulated signals, but GSM is much less uniform in its power output than CDMA. Even though the average exposure level over time may be the same, hypothetically there could be a difference in biological effects, though there is no credible reason to expect any such differences.