SAR stands for specific absorption rate, a measure of the amount of radio frequency energy absorbed by the body when using a mobile phone. The SAR rating of your cell phone can be found in your instruction manual or possibly online at this Federal Communications Commission website. In the United States, the SAR cannot exceed 1.6 watts per kilogram.
The World Health Organization International Agency for the Research on Cancer’s classification of wireless radiofrequency frequencies a Class 2B carcinogen includes wireless radiation from any transmitting source such as cellphones, baby monitors, tablets, cell towers, radar, other wifi, etc. The radiofrequency classification applies to RF-EMF in the range of 30 KHz to 300 GHz emitted from any device. Cell phone frequencies commonly start at 900 MHz (with some cell phones having up to 7 antennas all at different frequencies) and Wi-Fi device frequencies are at 2.45 GHz and 5GHz.
The purpose of the study was to investigate the effect of 2.45 GHz microwave radiation (2 h/day for 35 days) on the male rat brain. MWR-exposed rats showed significantly increased comet head, tail length and tail movement, as well as decrease of antioxidant enzymes. Researchers conclude that the chronic exposure to these radiations may cause significant damage to brain, which may be an indication of possible tumour promotion.
The present study aimed to investigate the effects of chronic low-intensity microwave exposure (900, 1800 or 2450 MHz for 180 days) on cognitive function, heat shock protein 70 (HSP70), and DNA damage in the rat brain. The results showed declined cognitive function, elevated HSP70 level, and DNA damage in the brain of microwave-exposed animals. The results indicated that, chronic low-intensity microwave exposure in the frequency range of 900 to 2450 MHz may cause hazardous effects on the brain.
Exposure to non-thermal radio frequency radiation from Wi-Fi and cellular phones can disrupt normal cellular development, especially fetal development. A 2004 animal study linked exposure to delayed kidney development.  These findings were supported by a 2009 Austrian study. In fact, the disruption of protein synthesis is so severe that authors specifically noted, “this cell property is especially pronounced in growing tissues, that is, in children and youth. Consequently, these population groups would be more susceptible than average to the described effects.”  In short, bathing the developmentally young in Wi-Fi increases their risk of developmental issues.
The most compelling evidence though comes from a Swedish team of cancer experts whose research stretches back 15 years. The results clearly demonstrate “a consistent association between long-term use of cell phone and cordless phones and glioma and acoustic neuroma”. Overall, they found that using a cell phone for more than a decade significantly increases the risk of a malignant tumour by almost two times with an analogue cell phone and by nearly four times with a digital phone. Interestingly, the risks were even higher for people who had started using mobiles as teenagers.