Aim: 

The question whether high-frequency electromagnetic fields (EMF) may cause biological effects is of special interest for public health. The main drawback of "in vivo"EMF exposure is the coexistance of stressors other than radiations, mainly represented by animal immobilization inside narrow cells. Therefore, the development of more suitable exposure systems should be promoted.

Methods: 

A novel exposure system, generating 1.8 GHz EMF radiations for biomedical and behavioral study on animal models, was designed and implemented. This system is based on a reverberation chamber. An input power up to 5 W can be sent to an indoor transmitting antenna and an electric field strentgh (E) more than 90 V/m can be reached inside the chamber.

Results: 

The system was characterized at differeent input powers (0.02–4.5 W), measuring E in different points, by means of a miniature sensor. Phantoms were realized and filled up with 300 mL of 0.9% (w/v) NaCl solution in H₂O, thus resembling a small laboratory animal body mass, and E was measured. Several simulations were performed by moving the phantoms across the chamber or putting them still in different positions. Specific absorption rate (SAR) and the power efficiency (P_e)were determined at different power intensities. SAR values ranged between 4.1 × 10^-4 and 1.2 × 10^-1 W/kg, and P_e was about 0.025 W/kgW_imp.

Conclusion: 

The measured P_e value resulted ~15 times smaller than those obtained by other recent "in vivo" exposure systems, based on the TEM cell technology. Eventhough such a performance is the drawback of this system, it represents a great advantage for "in vivo" research applications as it may reproduce a habitat similar to the usual one for the animal.