Issues in electromagnetic field-biointeractions

Low level electromagnetic fields have been found to produce a variety of biological effects, though the mechanism of such interaction is still not completely understood. Cell membrane of the brain is a critical structure perceiving the action of microwaves, which has received greater attention in the recent past. The interactions of EMF with the living cells are considered as stochastic resonance, cooperative effects, non-equilibrium thermodynamic process and non-linear interactions. The living cells derive the energy from noise and pumps it into the modes of excitation at the driving frequency of an electromagnetic wave which give sufficient amplification of the signal and increase the signal to noise ratio. The non-linear mechanism plays their main role in the process of transmembrane coupling of the signal to the cytoplasm. The criteria for safe exposure limits of electromagnetic field to humans is also discussed.