Firstly, the viability of THz-exposed cells was compared to hyperthermic positive controls (40 °C). Additionally, to determine protein and/or DNA damage, the protein expression and gene expression was determined in THz-exposed cells in comparison to hyperthermic positive controls (40 °C) and genotoxic positive controls (UV exposure).
|Exposure duration||continuous for 5 min., 10 min., 20 min., 40 min., 80 min.|
The cellular temperatures increased by 3 °C during all THz exposures. The THz and hyperthermic exposure groups exhibited equivalent viability (levels of cell survival of 90 %) and heat shock protein expression (3.5-fold increases) for each exposure duration tested. The gene expression was unchanged in both groups; however, appreciable increases were observed in the genotoxic positive control group.
The results show that the exposure to 2.52 THz radiation generates primarily thermal effects in human dermal fibroblasts. The authors conclude that THz-induced effects may be accurately predicted with conventional thermal damage models.