The exceptional growth of mobile communications has introduced in increase in demand for electromagnetic research. Moreover, the industry is faced with challenges as a result of the immense spread of wireless technology is the growing health concern of the public and health agencies.
The wide availability of wireless and electromagnetic (EM) technology has led to concerns for adverse health implications on the human health. Equally, the EM interactions with biological materials have generated considerable interest among a variety of medical and industrial professionals due to their practical applications.
Several organisations and government agencies have already defined a number of guidelines restricting the human radiofrequency (RF) exposure to certain power levels. However, these guidelines are based on the thermal distress resulting from EM power absorptions and they still require conclusive scientific evidences on other possible non-thermal effects.
The first logical step towards understanding this topic is the characterisation of the EM field strengths and distributions within the exposed body or biological matter. In practice, direct field measurement inside the living species using an invasive probe technique is very difficult if not impossible.
In order to enable experimentation with tissues inside the body (in-vivo), a number of experimental and numerical solutions have been employed in different studies. Other types of studies, however, are based on evaluating the fields inside tissue samples in isolation from the body (in-vitro), e.g. tissue sample exposure to RF radiations.
Despite the apparent simplicity of assessment at this scale, many experimental and numerical difficulties are generated as a result of the smaller size or the thickness of the tissue sample. Furthermore, the utilisation of thin probes to measure the fields may add to the complexity of the problem due to the introduction of a singular point at the tip of the probe where the field tends to intensify. Beyond the tissue scale, a number of studies have looked into the underlying interaction mechanisms at the cellular and membrane scales.
At REC-T, we apply numerical dosimetry techniques to investigate the interaction of EM fields with living animals and with tissue samples located within exposure systems. The outcome of these evaluations and assessments are validated against experimental measurements of equivalent physical animals and systems. In general, the conclusions derived from this study is used shed further light into: (i) the EM power absorption distribution within the exposed animals or tissue samples; (ii) the implication of aging of animals on the interaction with EM fields; and (iii) the accuracy of the numerical algorithms used in numerical dosimetry studies. |