Effects of combined radiofrequency radiation exposure on levels of reactive oxygen species in neuronal cells

The objective of this study was to investigate the effects of the combined RF radiation (837 MHz CDMA plus 1950 MHz WCDMA) signal on levels of intracellular reactive oxygen species (ROS) in neuronal cells. Exposure of the combined RF signal was conducted at specific absorption rate values of 2 W/kg of CDMA plus 2 W/kg of WCDMA for 2 h. Co-exposure to combined RF radiation with either H
2
O
2
or menadione was also performed. The experimental exposure groups were incubator control, sham-exposed, combined RF radiation-exposed with or without either H
2
O
2
or menadione groups. The intracellular ROS level was measured by flow cytometry using the fluorescent probe dichlorofluorescein diacetate. Intracellular ROS levels were not consistently affected by combined RF radiation exposure alone in a time-dependent manner in U87, PC12 or SH-SY5Y cells. In neuronal cells exposed to combined RF radiation with either H
2
O
2
or menadione, intracellular ROS levels showed no statically significant alteration compared with exposure to menadione or H
2
O
2
alone. These findings indicate that neither combined RF radiation alone nor combined RF radiation with menadione or H
2
O
2
influences the intracellular ROS level in neuronal cells such as U87, PC12 or SH-SY5Y.