Epidemiological study (observational study)

Occupational extremely low frequency magnetic fields (ELF-MF) exposure and hematolymphopoietic cancers - Swiss National Cohort analysis and updated meta-analysis epidem.

By: Huss A, Spoerri A, Egger M, Kromhout H, Vermeulen R, Swiss National Cohort (SNC)

Published in: Environ Res 2018; 164: 467-474

Aim of study (acc. to author)

The association between occupational exposure to extremely low frequency magnetic fields and mortality from different types of leukemia and lymphoma was investigated in the Swiss National Cohort.

Further details

Additionally, a meta-analysis of the association between occupational exposure to extremely low frequency magnetic fields and risk of acute myeloid leukemia (AML) was performed.

Endpoint/type of risk estimation

leukemia and lymphoma

Type of risk estimation:

mortality

(hazard ratio (HR))

Exposure

- 50/60 Hz
- magnetic field
- occupational

Assessment

job exposure matrix: data on occupations at censuses 1990 and 2000

Exposure groups

Group	Description
Reference group 1	magnetic field exposure: low (median 0.11 µT)
Group 2	magnetic field exposure: medium (median 0.19 µT)
Group 3	magnetic field exposure: high (median 0.52 µT)

Population

Group:
- men
- women
Age: 30–65 years
Characteristics: participants of the Swiss National Cohort
Observation period: 1990 - 2008
Study location: Switzerland
Data source: death registry, Swiss National Cohort
Exclusion criteria: pensioners

Study size

Type	Value
Total	3,147,000

Statistical analysis method:

Cox proportional regressions analysis

(adjustment:

sex
education
nationality, language region and marital status

)

Results (acc. to author)

Overall, no association between mortality from different types of leukemia and lymphoma and occupational exposure to extremely low frequency magnetic fields was found. However, an increase of mortality from of myeloid leukemias and acute myeloid leukemia (AML) was observed in ever-high exposed men (HR 1.31, CI 1.02-1.67; HR 1.26, CI 0.93-1.70, respectively). Workers who had been highly exposed during their vocational training and at both censuses showed an increased hazard ratio (HR 2.24, CI 0.91-5.53; HR 2.75 and CI 1.11-6.83, respectively).
The authors concluded that no convincing evidence for an increased risk of death from different types of leukemia and lymphoma in workers exposed to high or medium levels of extremely low frequency magnetic fields was provided. However, an increased risk of acute myeloid leukemia in workers exposed to high levels for a longer duration was found. Observed risks are in line with meta-analyzed previous reports on exposure to extremely low frequency magnetic fields and risk for acute myeloid leukemia (RR 1.21, CI 1.08-1.37).

Study funded by

Swiss National Science Foundation (SNF)
ZonMw, The Netherlands

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