RF Radiation, even at low levels, causes tumors when the exposure is prolongued. World Health Organization holds that there is not sufficient data that connects brain tumors with radio-frequency exposure, admitting though that since the use of mobile phones was introduced in 1990, strong correlations between cancer cause and effect can not be made yet.
Modern-type cell-phones carry all the software goodies, but require an antenna that needs extra power boost to run at 4G.
5G implementations with 100 times the capacity of 4G are expected to increase the levels of radiation dramatically, with unknown health effects.
Large Mobile Operators and Phone Suppliers seem to ignore the early warning and have moved at full-speed in implementing the 5G Global Network due to the speed and cost benefits.