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Updated: Jul 28, 2026
09:43
Optimized Setup and Protocol for Magnetic Domain Imaging with In Situ Hysteresis Measurement
Published on: November 7, 2017
ELF magnetic fields in a city environment.
M Lindgren1, M Gustavsson, Y Hamnerius
1Department of Electromagnetics, Chalmers, Göteborg, Sweden. martin.lindgren@elmagn.chalmers.se
Bioelectromagnetics
|February 17, 2001
Summary
Extremely low frequency electromagnetic field (ELF-EMF) exposure, often overlooked outdoors, shows high levels in city environments. These elevated magnetic flux densities, similar to those linked to cancer risks, warrant inclusion in exposure assessments.
Area of Science:
- Environmental Health
- Public Health
- Electromagnetic Fields
Background:
- Epidemiological studies suggest a link between extremely low frequency electromagnetic field (ELF-EMF) exposure and cancer risks.
- Previous research primarily focused on residential and occupational ELF-EMF exposure.
- Outdoor environments are typically presumed to have low ELF-EMF levels.
Purpose of the Study:
- To investigate ELF-EMF magnetic flux densities in urban outdoor environments.
- To determine if city sidewalks present significant ELF-EMF exposure levels.
- To assess the relevance of outdoor ELF-EMF exposure in risk evaluations.
Main Methods:
- Mapping of ELF magnetic flux densities along selected city sidewalks.
- Measurement of magnetic flux densities in central Göteborg City, Sweden.
- Identification of sources contributing to elevated ELF-EMF levels.
Main Results:
- Approximately 50% of the measured street length exhibited ELF magnetic flux densities of 0.2 microT and above.
- These levels are comparable to those associated with increased cancer risks in epidemiological studies.
- High magnetic flux densities (> 1.0 microT) were detected near electrical infrastructure and devices.
Conclusions:
- Urban outdoor environments can have significant ELF-EMF exposure levels.
- Outdoor ELF-EMF exposure should be considered in comprehensive risk assessments and evaluations.
- Elevated flux densities are likely caused by stray currents and proximity to electrical equipment.
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