exposure of radiation from mobile phone&base station

Through public exposure to RF radiation is caused by various sources such as radio,tv broadcast masts,radar operation etc.the one that has caught the attention is the radiation from mobile phones.these operate in the 800-900 &1850-1990 mhz bands respectively.basically rf radiation from mobile phones to public is basically of two types
1-from the base station
2-mobile phones
Exposure from base station:a base station consists of a lower generally mounted on a building at heights between 15 to 30 meters.the tower consists 3diamensional antenna separated by 120 degrees by each other.the rf beam radiating from an antenna is narrow in the plate of elevation,with typical widths between 5&10 degrees.most base stations radiate about 20-40 watts.
Since base station are located in population area,persons living in the path of the beam are exposued to beam continuously.
Exposure from mobile phones:mobile phones consists of a radio transmitter,receiver&antenna through which it transmit&receive signals.the user of mobile phone is exposed toRF fields higher than the base station.it is because,a mobile phones radiates only about 2-3 watts at peak,it is held very close to head.so it gives high radiation to whole body to the user.