Electromagnetic fields

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Electromagnetic fields health The most
controversial issues in epidemiological research

• Prof. Dr. Martin Röösli
• Institute of Social and Preventive Medicine at
  Swiss Tropical Institute, Basel
• Associated Institute of the University of Basel

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Content

• Exposure to power lines
• childhood leukaemia
• Occupational exposure to ELF-MF
• leukaemia
• neurodegenerative diseases
• Mobile phone exposure
• brain tumour
• All type of electromagnetic fields
• symptoms (electromagnetic hypersensitivity)

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Childhood leukaemia and power lines
From Greenland, 2005
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Childhood leukaemia

• No consistent results from animal research no
  biological mechanism.
• Multiple-bias modelling (Greenland, 2005)
• (a) confounders uncontrolled shared causes of
  field exposure and leukaemia,
• (b) sampling and response biases possible
  uncontrolled associations of exposure and disease
  with selection and participation
• (c) measurement errors

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Results of multipe bias modelling (OR for gt0.3 µT)
meta-analysis without bias
Greenland, 2005
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IARC classification

• Possibly carcinogenic to humans

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Attributable leukaemia cases
Kheifets, EHP, 2006

• Attributable fraction due to power lines 0.1 -5
• Number of leukaemia cases in CH (0-15y) 55.
• ? 0.2-2 annual cases due to power lines.

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Occupational ELF-MF exposure

• Occupational exposures levels and duration are
  generally higher than in the everyday environment
  (e.g. welder, electrician, railway workers).
• Appealing for epidemiologic research.
• Limitations co-exposures, healthy worker effects

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Past and new studies of occupational ELF exposure
and leukemia
Kheifets et al. JOEM 2008
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Past and new studies of occupational ELF exposure
and brain tumours
Kheifets et al. JOEM 2008
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Occupational ELF-MF exposure and amyotrophic
lateral sclerosis (ALS)
Kheifets, OEM, 2009
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Occupational ELF-MF exposure and Alzheimers
disease (AD)
Kheifets, OEM, 2009
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Extent of occupational exposure
From Table 1 Hug, Röösli Rapp, Soz Prav Med,
2006
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Exposure levels from power lines
Type of power line Distance where 1 µT can occur
380kV 50-80m
220kV 40-55m
110kV 20-30m
50kV 15-25m
110kV cable 3-6m
Bafu, 2005
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Study on neurodegenerative disease and power line
exposure

• Cohort study of the whole Swiss population
• All deaths between 2000 and 2005
• Exposure distance of place of residence to the
  nearest powerline (220 and 380 kV)

Huss et al., AJE, 2009
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Alzheimers disease and distance to power line
adjusted for sex, educational level,
occupational attainment, urban-rural area, civil
status, language region, number of apartments per
building, and living within 50 m of a major road.
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Alzheimers disease and distance to power line
Huss et al., AJE, 2009
adjusted for sex, educational level,
occupational attainment, urban-rural area, civil
status, language region, number of apartments per
building, and living within 50 m of a major road.
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Other neurodegenerative diseases (Swiss study)

• No indication of an association for
• Parkinson disease
• Amyotrophic lateral sclerosis
• Multiple sclerosis

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Strengths/limitations

• Selection bias unlikely
• Confounding unlikely (control outcomes are not
  related to power lines total mortality, lung
  cancer, alcoholic liver disease, cancer of
  esophagus)
• Limited number of cases lt100m of power lines
• No modelling/measurement of exposure
• Diagnosis misclassification
• from the limitations one rather expects an
  underestimation of the risk than a spurious
  association

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Review of the EU Scientific Committee on Emerging
and Newly Identified Health Risks (SCENIHR), 2009
SCENIHR Research priorities (2009)
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Epidemiological papers about mobile phone exposure
from http//www.emf-portal.de
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Why brain tumour?

• No direct DNA damage (non-ionzing radiation)
• Hypothetical biological mechanisms discussed
  (e.g. free radicals, DNA repair mechanism) but no
  mechanism established for radio- and microwave
  frequency radiation
• Head is most exposed part of the body when using
  a mobile phone
• But why tumours and not other head related
  outcomes???

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INTERPHONE Mobile phone and cancer
SCENIHR 2009
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Time trends of male brain tumour cancer rates
Incidence rate per 100,000 in Denmark, Finland,
Norway, and Sweden, 1974 2003
Glioma
Meningioma
triangles 60 79 years squares 40 59
years Circles 20 39 years
Deltour et al., JNCI, 2009
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Time trends of female brain tumour cancer rates
Incidence rate per 100,000 in Denmark, Finland,
Norway, and Sweden, 1974 2003
Glioma
Meningioma
triangles 60 79 years squares 40 59
years Circles 20 39 years
Deltour et al., JNCI, 2009
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Summary brain tumour

• Many studies available.
• Many studies and cancer registries allows to
  identify a possible risk if present.
• Inherent uncertainties regarding long term use.

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Electromagnetic Hypersensitivity (EHS)

• Other terms
• Electrosensitivity
• Idiopathic environmental Intolerances (IEI-EMF)
• EHS is characterized by a variety of non-specific
  symptoms, which afflicted individuals attribute
  to exposure to EMF (WHO, fact sheet N 296).
• No established biological mechanism

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3 different aspects of EHS

• Perception of low-level fields sensibility
  (Leitgeb and Schröttner, 2003)provocation
  studies
• Symptoms and RF-EMF short termprovocation
  studies / randomized trials / human laboratory
  study
• Symptoms and RF-EMF long termepidemiological/obs
  ervational studies

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Perception of low level RF-EMF under double blind
conditions
Röösli, EnvRes 2008
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Symptoms, well-being acute effects
effect1)
1) at least 1out of several
no effect
) near field (mobile phone) o) far field (base
station)
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Symptoms, well-being Long term effects
Major Challenge
Subjective reporting of symptoms
Knowledge about exposure

• Most cross-sectional studies based on measured
  exposure levels do not indicate an increased
  risk Hutter et al. 2006, Thomas et al. BioEM,
  2008 Berg-Beckhoff et al., 2009, Kühnlein et al.
  BioEM
• By design, cross-sectional studies are limited in
  terms of causality.

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Conclusions

• childhood leukaemia and exposure to power lines
• neurodegenerative diseases and ELF-MF
• adult Leukaemia/brain cancer and ELF-MF
• brain tumour and use of mobile phones
• electromagnetic hypersensitivity and EMF