Effects of Electromagnetic Fields on Serum Lipids in Workers of a Power Plant

Journal name: Environmental Science and Pollution Research

Zhaopin Wang1,3†, Lijuan Wang1,3†, Shuangshuang Zheng1,3, Zheyuan Ding1,3, Hui Liu1,3, Wen Jin1,3, Yifeng Pan1,3, Zexin Chen1,3, Ying Fei1,3, Guangdi Chen2, Zhengping Xu2, Yunxian Yu1,3*

1 Department of Epidemiology & Health Statistics, School of Public Health, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China

2 Bioelectromagnetics Laboratory, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China

3 Chronic Disease Research Institute, School of Public Health, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China

† Equal contributors

* Correspondence and reprint requests should be addressed to:

Yunxian Yu, MD, PhD

Department of Epidemiology & Health Statistics, School of Public Health, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China

866 Yu-Hang-Tang Road, Xihu District, Hangzhou 310058, Zhejiang, China

Tel: +86-571-88208191

Fax: +86-571-88208194

E-mail:

Supplementary Table 1. Joint effectsa of various occupational EMF exposures on serum lipids levels in 2010 (n = 544).
Parameters / Occupational Exposure / Other Occupational Exposures / Mean ± SD / β (SE) / P value
Employment Duration, years
TC, mmol/L / Low / < 24 (N = 56) / 4.41 ± 0.74 / Ref. / --
≥ 24 (N = 61) / 4.72 ± 1.06 / 0.28 (0.17) / 0.091
High / < 24 (N = 213) / 4.66 ± 0.84 / 0.39 (0.14) / 0.005
≥ 24 (N = 214) / 4.74 ± 0.86 / 0.37 (0.14) / 0.009 group with
LDL-c, mmol/L / Low / < 24 (N = 56) / 2.44 ± 0.60 / Ref. / --
≥ 24 (N = 61) / 2.67 ± 0.83 / 0.21 (0.14) / 0.126
High / < 24 (N = 213) / 2.61 ± 0.74 / 0.25 (0.11) / 0.031
≥ 24 (N = 214) / 2.67 ± 0.69 / 0.24 (0.12) / 0.043
HDL-c, mmol/L / Low / < 24 (N = 56) / 1.54 ± 0.33 / Ref. / --
≥ 24 (N = 61) / 1.45 ± 0.26 / -0.06 (0.05) / 0.284
High / < 24 (N = 213) / 1.49 ± 0.33 / 0.01 (0.05) / 0.806
≥ 24 (N = 214) / 1.51 ± 0.35 / 0.05 (0.05) / 0.330
ln TGb / Low / < 24 (N = 56) / -0.16 ± 0.47 / Ref. / --
≥ 24 (N = 61) / 0.12 ± 0.57 / 0.30 (0.14) / 0.038
High / < 24 (N = 213) / 0.04 ± 0.56 / 0.31 (0.12) / 0.010
≥ 24 (N = 214) / 0.04 ± 0.60 / 0.26 (0.12) / 0.037
Occupational Exposure Durationc, hours/day
TC, mmol/L / Low / < 3.37 (N = 93) / 4.62 ± 0.92 / Ref. / --
≥ 3.37 (N = 24) / 4.37 ± 0.97 / -0.21 (0.21) / 0.305
High / < 3.37 (N = 227) / 4.74 ± 0.80 / 0.24 (0.12) / 0.036
≥ 3.37 (N = 200) / 4.65 ± 0.91 / 0.12 (0.12) / 0.313
LDL-c, mmol/L / Low / < 3.37 (N = 93) / 2.59 ± 0.70 / Ref. / --
≥ 3.37 (N = 24) / 2.45 ± 0.88 / -0.12 (0.17) / 0.464
High / < 3.37 (N = 227) / 2.64 ± 0.66 / 0.11 (0.09) / 0.235
≥ 3.37 (N = 200) / 2.64 ± 0.77 / 0.09 (0.10) / 0.347
HDL-c, mmol/L / Low / < 3.37 (N = 93) / 1.51 ± 0.30 / Ref. / --
≥ 3.37 (N = 24) / 1.41 ± 0.29 / -0.04 (0.07) / 0.598
High / < 3.37 (N = 227) / 1.53 ± 0.35 / 0.08 (0.04) / 0.032
≥ 3.37 (N = 200) / 1.47 ± 0.33 / 0.02 (0.04) / 0.540
ln TGb / Low / < 3.37 (N = 93) / -0.03 ± 0.57 / Ref. / --
≥ 3.37 (N = 24) / 0.03 ± 0.40 / -0.11 (0.18) / 0.532
High / < 3.37 (N = 227) / 0.06 ± 0.60 / 0.16 (0.10) / 0.116
≥ 3.37 (N = 200) / 0.02 ± 0.56 / 0.03 (0.10) / 0.780
Walkie Talkie
TC, mmol/L / Low / No (N = 99) / 4.68 ± 0.94 / Ref. / --
Yes (N = 18) / 4.00 ± 0.61 / -0.65 (0.22) / 0.003
High / No (N = 252) / 4.77 ± 0.84 / 0.15 (0.11) / 0.174
Yes (N = 175) / 4.60 ± 0.86 / 0.03 (0.13) / 0.838
LDL-c, mmol/L / Low / No (N = 99) / 2.64 ± 0.74 / Ref. / --
Yes (N = 18) / 2.16 ± 0.60 / -0.46 (0.18) / 0.011
High / No (N = 252) / 2.69 ± 0.73 / 0.07 (0.09) / 0.442
Yes (N = 175) / 2.57 ± 0.69 / 0.00 (0.11) / 0.997
HDL-c, mmol/L / Low / No (N = 99) / 1.51 ± 0.31 / Ref. / --
Yes (N = 18) / 1.36 ± 0.23 / -0.08 (0.07) / 0.279
High / No (N = 252) / 1.50 ± 0.35 / 0.05 (0.04) / 0.178
Yes (N = 175) / 1.51 ± 0.33 / 0.03 (0.04) / 0.436
ln TGb / Low / No (N = 99) / -0.01 ± 0.55 / Ref. / --
Yes (N = 18) / -0.07 ± 0.48 / -0.25 (0.19) / 0.180
High / No (N = 252) / 0.09 ± 0.58 / 0.11 (0.10) / 0.267
Yes (N = 175) / -0.03 ± 0.58 / 0.01 (0.11) / 0.896
EMF, electromagnetic field ; TC, total cholesterol; LDL-c, low density lipoprotein cholesterol; HDL-c, high density lipoprotein cholesterol; TG, triglyceride
a Adjustment for age, gender, BMI, marital status, education level, labor intensity, tea drinking, alcohol drinking, cigarette smoking, work stress and workshop
b ln TG indicated the natural log transformation of TG
c Self-reported occupational EMF exposure duration per day on average in working place
Bold represents statistical significance
Supplementary Table 2. Joint effectsa of occupational and non-occupational EMF exposures on serum lipids levels in 2010 (n = 544).
Parameters / Occupational exposure / Non-occupational exposures / Mean ± SD / β (SE) / P value
Electric fee, yuan/month
TC, mmol/L / Low / < 150 (N = 36) / 4.44 ± 0.81 / Ref. / --
≥ 150 (N = 81) / 4.63 ± 0.98 / 0.28 (0.17) / 0.101
High / < 150 (N = 163) / 4.58 ± 0.88 / 0.31 (0.17) / 0.057
≥ 150 (N = 264) / 4.77 ± 0.83 / 0.50 (0.16) / 0.002
LDL-c, mmol/L / Low / < 150 (N = 36) / 2.53 ± 0.61 / Ref. / --
≥ 150 (N = 81) / 2.58 ± 0.79 / 0.17 (0.14) / 0.237
High / < 150 (N = 163) / 2.54 ± 0.68 / 0.14 (0.14) / 0.288
≥ 150 (N = 264) / 2.70 ± 0.73 / 0.32 (0.13) / 0.017
HDL-c, mmol/L / Low / < 150 (N = 36) / 1.39 ± 0.27 / Ref. / --
≥ 150 (N = 81) / 1.54 ± 0.30 / 0.07 (0.06) / 0.248
High / < 150 (N = 163) / 1.51 ± 0.35 / 0.14 (0.05) / 0.011
≥ 150 (N = 264) / 1.49 ± 0.33 / 0.09 (0.05) / 0.103
ln TG# / Low / < 150 (N = 36) / 0.02 ± 0.45 / Ref. / --
≥ 150 (N = 81) / -0.04 ± 0.57 / 0.10 (0.15) / 0.490
High / < 150 (N = 163) / -0.00 ± 0.57 / 0.13 (0.14) / 0.367
≥ 150 (N = 264) / 0.07 ± 0.59 / 0.24 (0.14) / 0.082
Mobile Phone Fee, yuan/month
TC, mmol/L / Low / < 55 (N = 55) / 4.53 ± 0.94 / Ref. / --
≥ 55 (N = 62) / 4.61 ± 0.93 / 0.02 (0.16) / 0.892
High / < 55 (N = 213) / 4.73 ± 0.89 / 0.26 (0.14) / 0.062
≥ 55 (N = 214) / 4.67 ± 0.81 / 0.24 (0.14) / 0.098
LDL-c, mmol/L / Low / < 55 (N = 55) / 2.50 ± 0.78 / Ref. / --
≥ 55 (N = 62) / 2.62 ± 0.70 / 0.02 (0.13) / 0.859
High / < 55 (N = 213) / 2.64 ± 0.72 / 0.14 (0.11) / 0.213
≥ 55 (N = 214) / 2.63 ± 0.71 / 0.16 (0.12) / 0.180
HDL-c, mmol/L / Low / < 55 (N = 55) / 1.56 ± 0.33 / Ref. / --
≥ 55 (N = 62) / 1.43 ± 0.27 / 0.00 (0.05) / 0.965
High / < 55 (N = 213) / 1.54 ± 0.39 / 0.07 (0.05) / 0.115
≥ 55 (N = 214) / 1.46 ± 0.28 / 0.05 (0.05) / 0.327
ln TG# / Low / < 55 (N = 55) / -0.11 ± 0.51 / Ref. / --
≥ 55 (N = 62) / 0.07 ± 0.55 / -0.01 (0.14) / 0.942
High / < 55 (N = 213) / -0.00 ± 0.62 / 0.15 (0.12) / 0.218
≥ 55 (N = 214) / 0.09 ± 0.54 / 0.09 (0.12) / 0.455
EMF, electromagnetic field ; TC, total cholesterol; LDL-c, low density lipoprotein cholesterol; HDL-c, high density lipoprotein cholesterol; TG, triglyceride
a Adjustment for age, gender, BMI, marital status, education level, labor intensity, tea drinking, alcohol drinking, cigarette smoking, work stress and workshop
b ln TG indicated the natural log transformation of TG
Bold represents statistical significance
Supplementary Table 3. Adjusted effectsa of occupational EMF exposure on serum lipids levels from 2010 to 2011 (n = 544).
Parameters / Occupational EMF exposure / 2010 / 2011 / P value / Time*Groupb P value
TC, mmol/L / Low (N = 117) / 4.57 ± 0.93 / 4.37 ± 0.96 / < 0.0001 / 0.003
High (N = 427) / 4.70 ± 0.85 / 4.73 ± 0.97
LDL-c, mmol/L / Low (N = 117) / 2.56 ± 0.74 / 2.12 ± 0.88 / 0.0003 / 0.0006
High (N = 427) / 2.64 ± 0.72 / 2.45 ± 0.83
HDL-c, mmol/L / Low (N = 117) / 1.49 ± 0.30 / 1.50 ± 0.31 / 0.234 / 0.046
High (N = 427) / 1.50 ± 0.34 / 1.49 ± 0.31
ln TGc / Low (N = 117) / -0.02 ± 0.54 / 0.31 ± 0.55 / 0.083 / 0.381
High (N = 427) / 0.04 ± 0.58 / 0.39 ± 0.59
EMF, electromagnetic field ; TC, total cholesterol; LDL-c, low density lipoprotein cholesterol; HDL-c, high density lipoprotein cholesterol; TG, triglyceride
a Adjustment for age, gender, BMI, marital status, education level, labor intensity, tea drinking, alcohol drinking, cigarette smoking, work stress and workshop
b Time*Group indicated the interaction of occupational EMF exposure with time (years)
c ln TG indicated the natural log transformation of TG
Bold represents statistical significance