SESSION 1. NEW/EMERGING WORKPLACE RISK RISKS POSED BY ELECTROMAGNETIC RADIATION OR USE OF IT EQUIPMENT Frank de Vocht Centre of Occupational and Environmental Health The University of Manchester, UK THE ELECTROMAGNETIC SPECTRUM BACKGROUND Workers may be exposed to SMF (0Hz), ELF-EMF (50- 60Hz) and RF-EMF (3Khz – 300 GHz) x-rays during especially medical diagnostics not discussed here Population ELF-EMF and RF-EMF exposure low, and negligible for static EMF. First study a link between increased cancer risk and employment as high-voltage substation workers was already published in 1966 (Asanova et al. Gig Tr Prof Zabol. 1966; 10(5): 50-2) Exposure: increasing in the previous decades in many occupational settings expanded to new industries and occupations “ELECTRIC” OCCUPATIONS (STATIC AND ELF) Static magnetic fields aluminum industry chloralkali production certain welding processes train systems using DC power supplies magnetic resonance (NMR and MRI) systems Extremely low-frequency (ELF) high exposure may occur in generation and transmission of electric power ubiquitous through the use of IT equipment As such, ‘electric occupations’ now also include: computer programmers, bookkeepers, clerks, accountants,… “ELECTRIC” OCCUPATIONS (RF) Radiofrequency (RF) main source mobile telephones occupations that may expose workers to RF-EMF include: radar technicians, radio and telegraph operators, telecommunication manufacturing occupations dielectric heat sealing workers workers using industrial heating equipment manufacturing semiconductor chips or microelectronic devices maintaining medical EMF equipment OCCUPATIONAL EMF EXPOSURE AND CANCER RISK Occupational studies have primarily focused on: leukemia and leukemia subtypes brain cancer breast cancer Results across studies so far remains inconsistent The most recent comprehensive meta-analysis (1993- 2007)* indicated increased risks: 14% for brain cancer (95%CI 1.07 – 1.22) 16% for leukemia. (95%CI 1.11 – 1.22) * Kheifets, Monroe et al. J Occup Environ Med 2008; 50(6):677-88 OCCUPATIONAL EMF EXPOSURE AND CANCER RISK FROM: Kheifets, Monroe et al. J Occup Environ Med 2008; 50(6):677-88 OCCUPATIONAL EMF EXPOSURE AND CANCER RISK However, most recent study (November 2013): 120,852 men and women aged 5-69 in 1986 No increased risk on incidence of lung, breast or brain cancer High ELF-EMF exposure acute myeloid leukemia: HR 2.15 [1.06-4.35] follicular lymphoma: HR 2.78 [1.00-5.77] Cumulative ELF-EMF exposure Significant, positive association with FL but not AML among men. OCCUPATIONAL EMF EXPOSURE & NEURODEGENERATIVE DISEASES Neurodegenerative diseases*, including : Alzheimer’s Disease (Santibanez et al. Occup Environ Med 2008;64(11):723-32) Parkinson’s Disease (Wechsler et al. Neurotox 1992;12(3):387-92) Dementia (Feychting et al. 1998;24(1):46-53) Amyotrophic Lateral Sclerosis (ALS) (Johansen. Scan J WE&H 2004;30 (S1):1-30) The link with ALS suggested to be associated with electric shocks rather than with ELF-EMF or RF-EMF exposure (Li and Sung. Am J Ind Med 2003;43(2):212-20.). * Feychting et al. Annu Rev Public Health 2005;26:165-89 OCCUPATIONAL EMF EXPOSURE AND OTHER EFFECTS Short term neurobehavioral and wellbeing effects MR engineers (de Vocht et al. J Magn Reson Imaging 2006;23(9):197-204) nurses working with MRI systems (Wilén & de Vocht. Eur J Radiol 2011;80(2):510-3) Increased suicide rates (van Wijngaarden et al Occup Environ Med 2000;57(4):258-63 & jOEM 2003;45(1):96-101) Biological effects tissue heating (RF) immune system disturbances (Johansson. Pathophysiology 2009;16(2-3):157-77) chromosomal aberration and micronuclei frequencies(amongst power generation and transmission workers). (Valjus et al. Rad Environ Biophys 1993;32(4):325-36; Nordenson et al. Rad Environ Biophys 1988;27(1):39-47) Overall evidence of increased health risk with occupational exposure to SMF, ELF and RF remains inconsistent. (Feychting et al. Annu Rev Public Health 2005;26:165-189; Johansen. Scand J WE&H 2004;S1:1-30) PARENTAL AND MATERNAL EMF EXPOSURE May cause adverse health effects in their children development of childhood cancers Smulevich et al. Int J Cancer 1999;83(6):718-22; Pearce et al. Pediatric Blood Cancer 2007;49(3):280-6 increased risk of birth defects Blaasaas et al. Occup Environ Med 2002;59(2):92-7 No data to indicate that that EMF exposure in the range up to RF-EMF directly damages DNA this may indicate EMF may cause epigenetic modifications However, other studies have shown lower cancer risks absence of any excess cancer risk Hug et al. Am J Epi 2010;171(1):27-35; Sorahan et al. Am J Ind Med 1999; 35(4): 348-57 No effect on birth outcomes Tonqvist. jOEM 1998; 40(2):111-7 PROBLEMS WITH EMF STUDIES Relevant exposure metric unknown Biological mechanism of interaction unknown No unexposed populations Co-exposure to chemicals More so than in studies investigating occupational exposure to chemicals important problems are: High spatial variability in exposure For example, electrical wiring in a building (McElroy et al. jOEM 2007;49(3):266-74) CONCLUSIONS / WHAT TO EXPECT… In short, the answer is that we don’t know… However, it is fair to say that if it was something serious (like for example asbestos) it would have been shown by now… With respect to cancers, if anything, it may be (rare) subtypes... However, exposure is only expected to keep increasing… Excerpt from: Frank de Vocht. Chapter 3. Occupational EMF Studies In: Epidemiology of electromagnetic fields. Röösli M (ed.). 2014 (In press) [email protected] EXTRA SLIDES RADIO SPECTRUM Frequency Wavelength Designation Abbreviation Extremely low 3 – 30 Hz 105 – 104 km ELF frequency 30 – 300 Hz 104 – 103 km Super low frequency SLF 300 – 3000 Hz 103 – 100 km Ultra low frequency ULF 3 – 30 kHz 100 – 10 km Very low frequency VLF 30 – 300 kHz 10 – 1 km Low frequency LF 300 kHz – 3 MHz 1 km – 100 m Medium frequency MF 3 – 30 MHz 100 – 10 m High frequency HF 30 – 300 MHz 10 – 1 m Very high frequency VHF 300 MHz – 3 GHz 1 m – 10 cm Ultra high frequency UHF 3 – 30 GHz 10 – 1 cm Super high frequency SHF Extremely high 30 – 300 GHz 1 cm – 1 mm EHF frequency Tremendously high 300 GHz - 3000 GHz 1 mm - 0.1 mm THF frequency OTHER PROBLEMS… Lack of funding Lack of a known biological mechanism But also… EXPOSURE ASSESSMENT What exposure metric to measure? Peak, average, duration? What frequency? Regular wave shape, or transients (“dirty electricity”)? de Vocht. J Expo Sci Environ Epi 2010; 20(5):39-405 .