The carousel type exposure system (already used in the reference article) consisted of a small anechoic chamber, a round table with eight tubes, where rats were kept, and a quarter-wavelength monopole antenna on the metal floor.
The rats were divided into four groups: exposure, sham, cage control, and light control (LC) group. Rats in the sham group were placed in the exposure system without TDMA exposure. Those in the cage control group were not placed in the exposure system. Those in the LC group (positive control) were exposed on the last day to the light condition (400 lux) until measurement.
No significant differences in melatonin and serotonin levels were revealed between the exposure, sham, and cage control groups. These data suggest that short-term exposure to a 1439 MHzTDMA electromagnetic field, which is about four times stronger than that emitted by mobile phones, does not alter melatonin and serotonin synthesis in rats.