Radio-frequency Radiation (RF)
Modern communication technologies use pulsed or heavily modulated signal. These pulses are more effective on cellular level than previous, continuous wave technologies (like FM radio, NMT etc).
The World Health Organisation (WHO) and its IARC classified in 2011 radiofrequency radiation as possibly carsinogenic to humans. This classification is a compromise and real risk is perhaps much bigger.
Simply put, the most typical symptoms caused by RF radiation are:
"sleep problems, depressions, cerebral symptoms, joint problems, infections, skin problems, cardiovascular problems as well as disorders of the visual and auditory systems and the gastrointestinal tract" 
Majority of epidemiological studies of base stations  indicate an increased risk. 3G and new 4G (LTE) are seen in some research papers more riskier than for example GSM [1,2]. The Chronic Exposure research overview shows that various microwave transmitters have caused health problems to the population already for decades. We recommend the following review about microwave transmitters and biological effects.
Good to know: The mobile phone exposure consists of both radiofrequency (RF) radiation and extremely low frequency (ELF) radiation. Therefore, it's radiation type can not be classified as only RF radiation. Still, increased numbers of gliomas (brain tumours), parotid gland tumours and acoustic neuroma have been reported. Extensive (only) RF-radiation has been linked in occupational studies to leukemia and lymphoma (1 ,2,3)
We utilise Gigahertz Solutions HF59B instrument to measure radio-frequency radiation. When needed, a spectrum analyser is used as well.