60 male workers with employment in electric power generation (n=12), distribution (n=31) or utility maintenance and administration (n=17) of an electric utility participated in the study. Regardless of their employment, the subjects were divided into 4 groups (quartiles, n=15 each) according to the mean values of their personal magnetic fieldexposure: groups 1, 2, 3 and 4. 4 sampling trials were conducted during 1 year. In each trial, after a non-work baseline day and the following 3 working days, overnight urine samples were collected (days 0, 1, 2, and 3), respectively. This procedure was repeated quarterly over the year. Additionally, subjects provided a blood sample at the end of day 3 during their third quarter of participation. Melatonin was investigated because of its immunostimulating effect.
National Institute of Environmental Health Sciences/National Institute of Health (NIEHS/NIH), USA
Hosseinabadi MB et al.
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