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

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- (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, 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 (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)

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EXTRA SLIDES

RADIO SPECTRUM

Frequency Designation Abbreviation Extremely low 3 – 30 Hz 105 – 104 km ELF frequency

30 – 300 Hz 104 – 103 km Super SLF

300 – 3000 Hz 103 – 100 km ULF

3 – 30 kHz 100 – 10 km VLF

30 – 300 kHz 10 – 1 km Low frequency LF

300 kHz – 3 MHz 1 km – 100 m MF

3 – 30 MHz 100 – 10 m HF

30 – 300 MHz 10 – 1 m VHF

300 MHz – 3 GHz 1 m – 10 cm UHF

3 – 30 GHz 10 – 1 cm 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