Amyotrophic lateral sclerosis, occupational exposure to extremely low frequency magnetic fields and electric shocks: a systematic review and meta-analysis

Hamed Jalilian 1 , Kamran Najafi 2 , Yahya Khosravi 3 ,  and Martin Röösli 4 , 5
  • 1 Department of Occupational Health and Safety Engineering, Faculty of Health, Qom University of Medical Sciences, Qom, Iran
  • 2 Student Research Committee, Hamedan University of Medical Sciences, Hamedan, Iran
  • 3 Department of Occupational Health and Safety Engineering, School of Health, Research Center for Health, Safety and Environment, Non-communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran
  • 4 Swiss Tropical and Public Health Institute, Basel, Switzerland
  • 5 University of Basel, Basel, Switzerland
Hamed JalilianORCID iD: https://orcid.org/0000-0002-5423-9442, Kamran Najafi, Yahya Khosravi
  • Corresponding author
  • Department of Occupational Health and Safety Engineering, School of Health, Research Center for Health, Safety and Environment, Non-communicable Diseases Research Center, Alborz University of Medical Sciences, Karaj, Iran
  • Email
  • Search for other articles:
  • degruyter.comGoogle Scholar
and Martin Röösli
  • Swiss Tropical and Public Health Institute, Basel, Switzerland
  • University of Basel, Basel, Switzerland
  • Search for other articles:
  • degruyter.comGoogle Scholar

Abstract

Exposure to extremely low frequency magnetic fields (ELF-MF) and electric shocks occurs in many workplaces and occupations but it is unclear whether any of these exposures cause Amyotrophic lateral sclerosis (ALS). The aim of this systematic review and meta-analysis is to explore whether occupational exposure to ELF-MF and/or electric shocks are risk factor for ALS. We searched PubMed, Embase, and Web of Science databases up to the end of 2019. Pooled risk estimates were calculated using random-effects meta-analysis including exploration of the sources of heterogeneity between studies and publication bias. Twenty-seven publications fulfilled the inclusion criteria. We found a weak, significant, association between occupational exposure to ELF-MF and the risk of ALS (RRPooled estimate: 1.20; 95%CI: 1.05, 1.38) with moderate to high heterogeneity (I2=66.3%) and indication of publication bias (PEgger’s test=0.03). No association was observed between occupational exposure to electric shocks and risk of ALS (RRPooled estimate: 0.97; 95%CI: 0.80, 1.17) with high heterogeneity (I2=80.5%), and little indication for publication bias (PEgger’s test=0.24). The findings indicate that occupational exposure to ELF-MF, but not electric shocks, might be a risk factor for ALS. However, given the moderate to high heterogeneity and potential publication bias, the results should be interpreted with caution.

  • 1.

    Kiernan, MC, Vucic, S, Cheah, BC, Turner, MR, Eisen, A, Hardiman, O, et al. Amyotrophic lateral sclerosis. Lancet 2011;377:942–55. https://doi.org/10.1016/s0140-6736(10)61156-7.

    • Crossref
    • PubMed
    • Export Citation
  • 2.

    Mitchell, JD, Borasio, GD. Amyotrophic lateral sclerosis. Lancet 2007;369:2031–41. https://doi.org/10.1016/s0140-6736(07)60944-1.

    • Crossref
    • PubMed
    • Export Citation
  • 3.

    Wang, M-D, Gomes, J, Cashman, NR, Little, J, Krewski, D. A meta-analysis of observational studies of the association between chronic occupational exposure to lead and amyotrophic lateral sclerosis. J Occup Environ Med 2014;56:1235. https://doi.org/10.1097/jom.0000000000000323.

    • Crossref
    • PubMed
    • Export Citation
  • 4.

    Kamel, F, Umbach, DM, Bedlack, RS, Richards, M, Watson, M, Alavanja, MC, et al. Pesticide exposure and amyotrophic lateral sclerosis. Neurotoxicology 2012;33:457–62. https://doi.org/10.1016/j.neuro.2012.04.001.

    • Crossref
    • PubMed
    • Export Citation
  • 5.

    Peters, TL, Kamel, F, Lundholm, C, Feychting, M, Weibull, CE, Sandler, DP, et al. Occupational exposures and the risk of amyotrophic lateral sclerosis. Occup Environ Med 2017;74:87–92. https://doi.org/10.1136/oemed-2016-103700.

    • Crossref
    • PubMed
    • Export Citation
  • 6.

    Sutedja, N, Veldink, J, Fischer, K, Kromhout, H, Wokke, J, Huisman, M, et al. Lifetime occupation, education, smoking, and risk of ALS. Neurology 2007;69:1508–14. https://doi.org/10.1212/01.wnl.0000277463.87361.8c.

    • Crossref
    • PubMed
    • Export Citation
  • 7.

    Chen, H, Richard, M, Sandler, DP, Umbach, DM, Kamel, F. Head injury and amyotrophic lateral sclerosis. Am J Epidemiol 2007;166:810–6. https://doi.org/10.3109/17482960802320396.

    • Crossref
    • PubMed
    • Export Citation
  • 8.

    Vergara, X, Kheifets, L, Greenland, S, Oksuzyan, S, Cho, YS, Mezei, G. Occupational exposure to extremely low-frequency magnetic fields and neurodegenerative disease: a meta-analysis. J Occup Environ Med 2013;55:135–46. https://doi.org/10.1097/jom.0b013e31827f37f8.

    • Crossref
    • PubMed
    • Export Citation
  • 9.

    Jalilian, H, Najafi, K, Monazzam, MR, Khosravi, Y, Zamanian, Z. Assessment of static and extremely low-frequency magnetic fields in the electric-powered trains. Int J Occup Hyg 2017;9:105–12.

  • 10.

    Jalilian, H, Najafi, K, Monazzam, MR, Khosravi, Y, Jamali, J. Occupational exposure of train drivers to static and extremely low frequency magnetic fields in Tehran subway. Jundishapur J Health Sci 2017;9:e14329.

  • 11.

    Monazzam, MR, Jalilian, H, Najafi, K, Zakerian, SA. Single-Axis and three-Axis probe magnetic field meters in an occupational hygiene study: a comparative view. Int J Occup Hyg 2015;7:166–71.

  • 12.

    Monazzam, MR, Jalilian, H, Najafi, K, Zakerian, SA, Emkani, M, Hadadi, M. Environmental evaluation and employee’s exposure of a thermal power plant with extremely low frequency magnetic fields. Iran Occup Health J 2015;12:65–75.

  • 13.

    Jalilian, H, Monazzam, MR, Zakerian, SA, Zokaie, M, Najafi, K. Mental health status among workers exposed to extremely low frequency magnetic fields. Occup Med Quarterly J 2016;7:57–68.

  • 14.

    Bowman, JD. Exposures to ELF-EMF in the everyday environment. In: Röösli, M, editor. Epidemiology of electromagnetic fields. Boca Raton, FL, USA: CRC Press; 2014.

  • 15.

    Huss, A, Vermeulen, R, Bowman, JD, Kheifets, L, Kromhout, H. Electric shocks at work in Europe: development of a job exposure matrix. Occup Environ Med 2013;70:261–7. https://doi.org/10.1136/oemed-2012-100732.

    • Crossref
    • PubMed
    • Export Citation
  • 16.

    ACGIH. Kemper meadow drive. Cincinnati, OH: TLVs and BEIs; 2012.

  • 17.

    Bowman, JD, Touchstone, JA, Yost, MG. A population-based job exposure matrix for power-frequency magnetic fields. J Occup Environ Hyg 2007;4:715–28. https://doi.org/10.1080/15459620701528001.

    • Crossref
    • PubMed
    • Export Citation
  • 18.

    Koeman, T, Slottje, P, Schouten, LJ, Peters, S, Huss, A, Veldink, JH, et al. Occupational exposure and amyotrophic lateral sclerosis in a prospective cohort. Occup Environ Med 2017;74:578–85. https://doi.org/10.1136/oemed-2016-103780.

    • Crossref
    • Export Citation
  • 19.

    Huss, A, Spoerri, A, Egger, M, Kromhout, H, Vermeulen, R. Occupational exposure to magnetic fields and electric shocks and risk of ALS: the Swiss National Cohort. Amyotroph Lateral Scler Frontotemporal Degener 2015;16:80–5. https://doi.org/10.3109/21678421.2014.954588.

    • Crossref
    • PubMed
    • Export Citation
  • 20.

    Huss, A, Peters, S, Vermeulen, R. Occupational exposure to extremely low-frequency magnetic fields and the risk of ALS: a systematic review and meta-analysis. Bioelectromagnetics 2018;39:156–63. https://doi.org/10.1002/bem.22104.

    • Crossref
    • Export Citation
  • 21.

    Gunnarsson, LG, Bodin, L. Occupational exposures and neurodegenerative diseases—a systematic literature review and meta-analyses. Int J Environ Res Publ Health 2019;16. https://doi.org/10.3390/ijerph16030337.

  • 22.

    Gunnarsson, LG, Bodin, L. Amyotrophic lateral sclerosis and occupational exposures: a systematic literature review and meta-analyses. Int J Environ Res Publ Health 2018;15. https://doi.org/10.3390/ijerph15112371.

  • 23.

    Su, L, Jin, Y, Lou, H, Chen, G. RE: “associations of electric shock and extremely low-frequency magnetic field exposure with the risk of amyotrophic lateral sclerosis: the euro-motor project”. Am J Epidemiol 2019;188:1753–9. https://doi.org/10.1093/aje/kwz122.

    • Crossref
    • PubMed
    • Export Citation
  • 24.

    Moher, D, Liberati, A, Tetzlaff, J, Altman, DG, Group, P. Preferred reporting items for systematic reviews and meta-analyses: the PRISMA statement. PLoS Med 2009;6:e1000097. https://doi.org/10.1371/journal.pmed.1000097.

    • Crossref
    • PubMed
    • Export Citation
  • 25.

    EMF-Portal; 2017. Available from: http://www.emf-portal.de/.

  • 26.

    Buckley, J, Warlow, C, Smith, P. Motor neuron disease in England and Wales, 1959–1979. J Neurol Neurosurg Psychiatry 1983;46:197–205. https://doi.org/10.1136/jnnp.46.3.197.

    • Crossref
    • PubMed
    • Export Citation
  • 27.

    Repacholi, MH, Lerchl, A, Roosli, M, Sienkiewicz, Z, Auvinen, A, Breckenkamp, J, et al. Systematic review of wireless phone use and brain cancer and other head tumors. Bioelectromagnetics 2012;33:187–206. https://doi.org/10.1002/bem.20716.

    • Crossref
    • PubMed
    • Export Citation
  • 28.

    Jalilian, H, Teshnizi, SH, Roosli, M, Neghab, M. Occupational exposure to extremely low frequency magnetic fields and risk of Alzheimer disease: a systematic review and meta-analysis. Neurotoxicology 2018;69:242–52. https://doi.org/10.1016/j.neuro.2017.12.005.

    • Crossref
    • PubMed
    • Export Citation
  • 29.

    Pedersen, C, Poulsen, AH, Rod, NH, Frei, P, Hansen, J, Grell, K, et al. Occupational exposure to extremely low-frequency magnetic fields and risk for central nervous system disease: an update of a Danish cohort study among utility workers. Int Arch Occup Environ Health 2017:1–10. https://doi.org/10.1007/s00420-017-1224-0.

  • 30.

    Vergara, X, Mezei, G, Kheifets, L. Case-control study of occupational exposure to electric shocks and magnetic fields and mortality from amyotrophic lateral sclerosis in the US, 1991–1999. J Expo Sci Environ Epidemiol 2015;25:65–71. https://doi.org/10.1038/jes.2014.39.

    • Crossref
    • PubMed
    • Export Citation
  • 31.

    Fischer, H, Kheifets, L, Huss, A, Peters, TL, Vermeulen, R, Ye, WM, et al. Occupational exposure to electric shocks and magnetic fields and amyotrophic lateral sclerosis in Sweden. Epidemiology 2015;26:824–30. https://doi.org/10.1097/ede.0000000000000365.

    • Crossref
    • PubMed
    • Export Citation
  • 32.

    Sorahan, T, Mohammed, N. Neurodegenerative disease and magnetic field exposure in UK electricity supply workers. Occup Med (Lond) 2014;64:454–60. https://doi.org/10.1093/occmed/kqu105.

    • Crossref
    • PubMed
    • Export Citation
  • 33.

    Malek, AM, Barchowsky, A, Bowser, R, Heiman-Patterson, T, Lacomis, D, Rana, S, et al. Environmental and occupational risk factors for amyotrophic lateral sclerosis: a case-control study. Neurodegener Dis 2014;14:31–8. https://doi.org/10.1159/000355344.

    • Crossref
    • PubMed
    • Export Citation
  • 34.

    Parlett, LE, Bowman, JD, van Wijngaarden, E. Evaluation of occupational exposure to magnetic fields and motor neuron disease mortality in a population-based cohort. J Occup Environ Med 2011;53:1447–51. https://doi.org/10.1097/jom.0b013e318237a1d0.

    • Crossref
    • Export Citation
  • 35.

    Fang, F, Quinlan, P, Ye, W, Barber, MK, Umbach, DM, Sandler, DP, et al. Workplace exposures and the risk of amyotrophic lateral sclerosis. Environ Health Perspect 2009;117:1387–92. https://doi.org/10.1289/ehp.0900580.

    • Crossref
    • PubMed
    • Export Citation
  • 36.

    Roosli, M, Lortscher, M, Egger, M, Pfluger, D, Schreier, N, Lortscher, E, et al. Mortality from neurodegenerative disease and exposure to extremely low-frequency magnetic fields: 31 years of observations on Swiss railway employees. Neuroepidemiology 2007;28:197–206. https://doi.org/10.1159/000108111.

    • Crossref
    • PubMed
    • Export Citation
  • 37.

    Weisskopf, MG, McCullough, ML, Morozova, N, Calle, EE, Thun, MJ, Ascherio, A. Prospective study of occupation and amyotrophic lateral sclerosis mortality. Am J Epidemiol 2005;162:1146–52. https://doi.org/10.1093/aje/kwi343.

    • Crossref
    • PubMed
    • Export Citation
  • 38.

    Park, RM, Schulte, PA, Bowman, JD, Walker, JT, Bondy, SC, Yost, MG, et al. Potential occupational risks for neurodegenerative diseases. Am J Ind Med 2005;48:63–77. https://doi.org/10.1002/ajim.20178.

    • Crossref
    • PubMed
    • Export Citation
  • 39.

    Hakansson, N, Gustavsson, P, Johansen, C, Floderus, B. Neurodegenerative diseases in welders and other workers exposed to high levels of magnetic fields. Epidemiology 2003;14:420–6. https://doi.org/10.1097/00001648-200307000-00008. discussion 427-8.

    • Crossref
    • PubMed
    • Export Citation
  • 40.

    Feychting, M, Jonsson, F, Pedersen, NL, Ahlbom, A. Occupational magnetic field exposure and neurodegenerative disease. Epidemiology 2003;14:413–9. https://doi.org/10.1097/00001648-200307000-00007. discussion 427-8.

    • Crossref
    • PubMed
    • Export Citation
  • 41.

    Noonan, CW, Reif, JS, Yost, M, Touchstone, J. Occupational exposure to magnetic fields in case-referent studies of neurodegenerative diseases. Scand J Work Environ Health 2002;28:42–8. https://doi.org/10.5271/sjweh.645.

    • Crossref
    • PubMed
    • Export Citation
  • 42.

    Savitz, DA, Loomis, DP, Tse, CK. Electrical occupations and neurodegenerative disease: analysis of U.S. mortality data. Arch Environ Health 1998;53:71–4. https://doi.org/10.1080/00039899809605691.

    • Crossref
    • PubMed
    • Export Citation
  • 43.

    Savitz, DA, Checkoway, H, Loomis, DP. Magnetic field exposure and neurodegenerative disease mortality among electric utility workers. Epidemiology 1998;9:398–404. https://doi.org/10.1097/00001648-199807000-00009.

    • Crossref
    • PubMed
    • Export Citation
  • 44.

    Davanipour, Z, Sobel, E, Bowman, JD, Qian, Z, Will, AD. Amyotrophic lateral sclerosis and occupational exposure to electromagnetic fields. Bioelectromagnetics 1997;18:28–35. https://doi.org/10.1002/(sici)1521-186x(1997)18:1<28::aid-bem6>3.0.co;2-7.

    • Crossref
    • PubMed
    • Export Citation
  • 45.

    Strickland, D, Smith, SA, Dolliff, G, Goldman, L, Roelofs, RI. Amyotrophic lateral sclerosis and occupational history – a pilot case-control study. Arch Neurol 1996;53:730–3. https://doi.org/10.1001/archneur.1996.00550080044011.

    • Crossref
    • PubMed
    • Export Citation
  • 46.

    Gunnarsson, LG, Bodin, L, Soderfeldt, B, Axelson, O. A case-control study of motor neurone disease: its relation to heritability, and occupational exposures, particularly to solvents. Br J Ind Med 1992;49:791–8. https://doi.org/10.1136/oem.49.11.791.

    • PubMed
    • Export Citation
  • 47.

    Gunnarsson, LG, Lindberg, G, Soderfeldt, B, Axelson, O. Amyotrophic lateral sclerosis in Sweden in relation to occupation. Acta Neurol Scand 1991;83:394–8. https://doi.org/10.1111/j.1600-0404.1991.tb03970.x.

    • Crossref
    • PubMed
    • Export Citation
  • 48.

    Deapen, DM, Henderson, BE. A case-control study of amyotrophic lateral sclerosis. Am J Epidemiol 1986;123:790–9. https://doi.org/10.1093/oxfordjournals.aje.a114308.

    • Crossref
    • PubMed
    • Export Citation
  • 49.

    Peters, S, Visser, AE, D’Ovidio, F, Beghi, E, Chio, A, Logroscino, G, et al. Associations of electric shock and extremely low-frequency magnetic field exposure with the risk of amyotrophic lateral sclerosis. Am J Epidemiol 2019;188:796–805. https://doi.org/10.1093/aje/kwy287.

    • Crossref
    • PubMed
    • Export Citation
  • 50.

    Chen, GX, T’Mannetje, AM, Douwes, J, Van Den Berg, L, Pearce, N, Kromhout, H, et al. Occupation and motor neuron disease: a New Zealand case-control study. Occup Environ Med 2019;76:309–16. https://doi.org/10.1136/oemed-2018-105605.

    • Crossref
    • PubMed
    • Export Citation
  • 51.

    Dickerson, AS, Hansen, J, Kioumourtzoglou, MA, Specht, AJ, Gredal, O, Weisskopf, MG. Study of occupation and amyotrophic lateral sclerosis in a Danish cohort. Occup Environ Med 2018;75:630–8. https://doi.org/10.1136/oemed-2018-105110.

    • Crossref
    • Export Citation
  • 52.

    Huisman, MH, Seelen, M, van Boxmeer, L, Visser, AE, van Doormaal, PT, Raaphorst, J, et al. High and recent exposure to low frequency electromagnetic fields may increase the risk of amyotrophic lateral sclerosis, exogenous risk factors for amyotrophic lateral sclerosis. Ridderkerk, the Netherlands: Ridderprint BV; 2015.

  • 53.

    Kauppinen, T, Heikkila, P, Plato, N, Woldbaek, T, Lenvik, K, Hansen, J, et al. Construction of job-exposure matrices for the nordic occupational cancer study (NOCCA). Acta Oncol (Stockh) 2009;48:791–800. https://doi.org/10.1080/02841860902718747.

    • Crossref
    • Export Citation
  • 54.

    Vergara, XP, Fischer, HJ, Yost, M, Silva, M, Lombardi, DA, Kheifets, L. Job exposure matrix for electric shock risks with their uncertainties. Int J Environ Res Publ Health 2015;12:3889–902. https://doi.org/10.3390/ijerph120403889.

    • Crossref
    • Export Citation
  • 55.

    Wang, MD, Little, J, Gomes, J, Cashman, NR, Krewski, D. Identification of risk factors associated with onset and progression of amyotrophic lateral sclerosis using systematic review and meta-analysis. Neurotoxicology 2017;61:101–30. https://doi.org/10.1016/j.neuro.2016.06.015.

    • Crossref
    • PubMed
    • Export Citation
  • 56.

    Strickland, D, Smith, SA, Dolliff, G, Goldman, L, Roelofs, RI. Physical activity, trauma, and ALS: a case‐control study. Acta Neurol Scand 1996;94:45–50. https://doi.org/10.1111/j.1600-0404.1996.tb00038.x.

    • Crossref
    • Export Citation
  • 57.

    Trojsi, F, Monsurrò, MR, Tedeschi, G. Exposure to environmental toxicants and pathogenesis of amyotrophic lateral sclerosis: state of the art and research perspectives. Int J Mol Sci 2013;14:15286–311. https://doi.org/10.3390/ijms140815286.

    • Crossref
    • PubMed
    • Export Citation
  • 58.

    Bozzoni, V, Pansarasa, O, Diamanti, L, Nosari, G, Cereda, C, Ceroni, M. Amyotrophic lateral sclerosis and environmental factors. Funct Neurol 2016;31:7–19. https://doi.org/10.11138/FNeur/2016.31.1.007.

    • PubMed
    • Export Citation
  • 59.

    Abhinav, K, Al-Chalabi, A, Hortobagyi, T, Leigh, PN. Electrical injury and amyotrophic lateral sclerosis: a systematic review of the literature. J Neurol Neurosurg Psychiatry 2007;78:450–3.

    • PubMed
    • Export Citation
  • 60.

    Guyatt, G, Oxman, AD, Akl, EA, Kunz, R, Vist, G, Brozek, J, et al. Grade guidelines: 1. Introduction—GRADE evidence profiles and summary of findings tables. J Clin Epidemiol 2011;64:383–94. https://doi.org/10.1016/j.jclinepi.2010.04.026.

    • Crossref
    • PubMed
    • Export Citation
  • 61.

    Golbach, LA, Portelli, LA, Savelkoul, HF, Terwel, SR, Kuster, N, de Vries, RB, et al. Calcium homeostasis and low-frequency magnetic and electric field exposure: a systematic review and meta-analysis of in vitro studies. Environ Int 2016;92–93:695–706. https://doi.org/10.1016/j.envint.2016.01.014.

    • PubMed
    • Export Citation
  • 62.

    Simko, M. Cell type specific redox status is responsible for diverse electromagnetic field effects. Curr Med Chem 2007;14:1141–52. https://doi.org/10.2174/092986707780362835.

    • Crossref
    • PubMed
    • Export Citation
  • 63.

    Falone, S, Mirabilio, A, Carbone, MC, Zimmitti, V, Di Loreto, S, Mariggio, MA, et al. Chronic exposure to 50 Hz magnetic fields causes a significant weakening of antioxidant defence systems in aged rat brain. Int J Biochem Cell Biol 2008;40:2762–70. https://doi.org/10.1016/j.biocel.2008.05.022.

    • Crossref
    • PubMed
    • Export Citation
  • 64.

    Liebl, MP, Windschmitt, J, Besemer, AS, Schafer, AK, Reber, H, Behl, C, et al. Low-frequency magnetic fields do not aggravate disease in mouse models of Alzheimer’s disease and amyotrophic lateral sclerosis. Sci Rep 2015;5:8585. https://doi.org/10.1038/srep08585.

    • Crossref
    • PubMed
    • Export Citation
  • 65.

    Phillips, JL, Singh, NP, Lai, H. Electromagnetic fields and DNA damage. Pathophysiology 2009;16:79–88. https://doi.org/10.1016/j.pathophys.2008.11.005.

    • Crossref
    • PubMed
    • Export Citation
  • 66.

    Poulletier de Gannes, F, Ruffié, G, Taxile, M, Ladevèze, E, Hurtier, A, Haro, E, et al. Amyotrophic lateral sclerosis (ALS) and extremely low frequency (ELF) magnetic fields: a study in the SOD‐1 transgenic mouse model. Amyotroph Lateral Scler 2009;10:370–3. https://doi.org/10.3109/17482960802320396.

    • Crossref
    • PubMed
    • Export Citation
Purchase article
Get instant unlimited access to the article.
$42.00
Log in
Already have access? Please log in.


or
Log in with your institution

Journal + Issues

Reviews on Environmental Health is an international quarterly periodical that fills the need for rapid publication of specialized comprehensive review articles on hot topics in the field of environmental health. The journal is an inspiring forum for scientists, environmentalists, physicians, engineers and students active in the area of public health, including quality of life.

Search