Initial results published from a new study by the US National Toxicology Program (NTP), reported an association between exposure to radiation from cellphones and cancer development in rats
In June 2016 a report was published reviewing the partial findings of a comprehensive study conducted by the US National Toxicology Program to evaluate the association between exposure to radiofrequency radiation (RF) and cancer in rats. The study findings point towards a mild increase in risk of developing two types of tumors as a result of exposure to RF radiation.
During the study, whose cost was estimated as about 25 million dollars, rats were exposed to RF radiation using GSM and CDMA technology – which are in widespread use in cellular communication in the US (900-1900MHz frequency). Exposure strengths tested were at SAR levels 1.5, 3 and 6 Watts per kg. The rats were exposed to RF radiation for two years, 18 hours per day in cycles of 10 minutes with exposure and 10 minutes without, so that the overall duration of daily exposure was 9 hours.
A control group of rats was not exposed to radiation. This group was maintained in identical conditions to the study group but without RF radiation exposure.
The findings of the study pointed towards a low incidence of two types of tumor – malignant glioma in the brain and shwannoma in the heart (tumor of the cells covering the nerves), amongst male rats exposed to this radiation. These tumors did not appear in rats in the control group.
The report emphasized that “considering the widespread use and large number of people using cellular communication, even a small increase in the frequency of diseases caused by RF radiation exposure from these devices, may have significant effects on public health”.
It should be noted that the report only details findings regarding glioma of the brain and schwannoma of the heart and does not include all the outcomes that were examined, and that presentation of all the findings is expected in 2017. At the same time, the NTP noted that these partial findings were published and already communicated to additional regulatory agencies at this stage in order to inform them of the most up to date scientific knowledge so that the public could receive guidance regarding educated ways of using cellphones and additional end user devices involving RF radiation.
The findings of this study join the findings of the INTERPHONE study conducted by the International Agency for Research on Cancer (IARC), which were published in 2010 (18 countries including Israel participated in the study). The study evaluated the possible association between cellphone use and development of brain tumors (meningioma and glioma), acoustic neuroma and parotid gland tumors in adults. This study observed an increase in risk of developing malignant brain tumors (glioma) and acoustic neuroma amongst people in the upper decile of use compared to people who did not use cellphones. Additional risk was particularly observed in people who always held their cellphone on the same side where the tumor developed. A study performed in Israel showed similar results for salivary gland tumors.
The importance of the new study is that its findings strengthen the existing knowledge on the association between radiofrequency radiation exposure and development of cancer, not only at the level of epidemiological research (the interphone) but also at an additional research level, in vivo research.