Occupational magnetic field exposure among women in Stockholm County, Sweden

Abstract

Background: Most epidemiological studies on adverse health effects among women in relation to occupational magnetic field exposure have been based on information about men's exposure. Aims: To create a job-exposure matrix for occupational exposure to extremely low frequency magnetic fields among women. Methods and Results: Measurements were performed using personal magnetic field meters (Emdex Lite) carried by the subjects for 24 hours on a normal workday. Subjects were volunteer women working in the occupations identified as common among women in Stockholm County based on the 1980 census. A total of 471 measurements were made in 49 different occupations, with a minimum of 5 and a maximum of 24 measurements in each occupation. The included occupations cover about 85% of the female population gainfully employed in 1980. Parameters representing average and peak magnetic field exposures, temporal change in the exposure, and proportion of time spent above certain exposure levels were calculated both for the workday and for the total 24 hour period grouped by occupational titles. The occupations with higher than average exposure were cashiers, working proprietors in retail trade, air stewardesses, dental nurses, cooks, post-office clerks and kitchen maids. Conclusions: This new job-exposure matrix substantially increases the knowledge about magnetic field exposure among women and can be used for exposure assessment in future studies.

Occupational and environmental exposure to extremely low frequency-magnetic fields: a personal monitoring study in a large group of workers in Italy

“…In 75% of the workers the TWA am was lower than 0.28 mT; again this is in substantial agreement with data reported by Floderus et al (1996) and Forsse´n et al (2004), who observed a 751 percentile of 0.27 and 0.25 mT, respectively.…”

“…Considering that the workers studied were engaged in the main occupational activities in our region, and the agreement with data obtained in other Countries (Floderus et al, 1996;Forsse´n et al, 2004;Bowman et al, 2007;WHO, 2007), these results suggest that, usually, the occupational exposure to ELF-MF is low, a few orders of magnitude lower than the levels associated with acute adverse effects (ICNIRP, 1998), and, in most workers, also lower than the levels possibly related to suspected long-term adverse effects, such as childhood leukemia, in some epidemiological studies (Ahlbom et al, 2000).…”

“…For the group as a whole, median occupational TWA am was 0.14 mT: this level is consistent with the values observed by Floderus et al (1996) in 1098 male Swedish workers, and by Forsse´n et al (2004) in 471 women in Stockholm County.…”

“…Another difficulty in comparing our results is that in other studies different exposure evaluation methods, and different occupation classifications, such as the SOC, BOC or Nordic ISCO system, were applied (Floderus et al, 1996;Forsse´n et al, 2004;Bowman et al, 2007).…”

“…Moreover, due to ubiquity, ELF-MF exposure occurs not only at work, but also during non-working hours, both at home and outside. Accordingly, epidemiological studies on possible effects of ELF-MF should take into account the overall exposure both at work and elsewhere (McCurdy et al, 2001;Forsse´n et al, 2004;Feychting et al, 2005).…”