DEPRESSIVE SYMPTOMS IN WOMEN LIVING NEAR A 735 KV LINE

Abstract

Objectives 735 kV powerlines increase residential exposure to electric and magnetic fields (EMF) for people living nearby. Some studies have suspected effect of EMF on depressive symptoms and there is plausibility for such an effect via the melatonin pathway. Recently, we found that aged and overweight women living near high power lines had lower sulfatoxymelatonin excretion (Levallois et al 2001). The objective of this study was to compare symptoms of depression in women living near and far away from a high transmission line. Methods In the Quebec city area, 221 women living within 200 meters of a 735 kV line and 195 women living at least 400 meters from any power lines were recruited. Participants, aged between 20 and 74, were required to wear an EMDEX Lite meter for at least 36 hours to measure personal exposure to extremely low frequency magnetic field. Residential exposure to extremely low frequency electric field was assessed by spot measurements. Depressive symptoms in the last week were evaluated with the Center for Epidemiologic Depression scale (CESD) and, for a subsample of participants, with the Diagnostic Intervention Schedule (DIS). Information on risk factors for depression and lifestyle was gathered by questionnaire. Results Mean magnetic field exposure over 24 hours was three times higher for women living near a power line than women living farther away (p < 0.001) and residential electric field intensity was nearly twice in those living near the line (p < 0.001). Proportion of participants with high CESD score (>16) was similar in the two groups (p = 0.63) and the adjusted Odds Ratio for the presence of depressive symptoms in the exposed group was 1.01 (95%Cl: 0.61–1.66). Results were similar when considering higher CESD cut-off scores (19 and 25). In addition, there was no dose response relationship with either electric or magnetic field measurements. There was no modification effect of age or BMI. The DIS results will available at the conference. Acknowledgements Hydro-Québec and Electricité de France supported the melatonin study from which these results are derived.