The paper deals with an investigation of the possible effects of RF electromagnetic fields towards the environment and human health. An experimental facility was designed and built and in vitro experiments were carried out on thymic cell cultures. They were exposed for three and six hours to 144 MHz RF electromagnetic fields. The effects were analysed in terms of the possible variation of their thermophysical properties (density, viscosity, specific heat). Results showed that the tested configuration does not induce alterations of the thermophysical properties of the tested cell cultures.