Canada Health Alliance

Association between Extremely Low-Frequency Electromagnetic Fields Occupations and Amyotrophic Lateral Sclerosis: A Meta-Analysis

Hongjie Zhou et al.

Objectives: To estimate the relationship between exposure to extremely low-frequency electromagnetic fields (ELF-EMF) and the risk of amyotrophic lateral sclerosis (ALS) by a meta-analysis.

Methods: Through searching PubMed databases (or manual searching) up to April 2012 using the following keywords: ‘‘occupational exposure’’, ‘‘electromagnetic fields’’ and ‘‘amyotrophic lateral sclerosis’’ or ‘‘motor neuron disease’’, seventeen studies were identified as eligible for this meta-analysis. The associations between ELF-EMF exposure and the ALS risk were estimated based on study design (case-control or cohort study), and ELF-EMF exposure level assessment (job title or job- exposure matrix). The heterogeneity across the studies was tested, as was publication bias.

Results: Occupational exposure to ELF-EMF was significantly associated with increased risk of ALS in pooled studies (RR=1.29, 95%CI=1.02–1.62), and case-control studies (OR=1.39, 95%CI=1.05–1.84), but not cohort studies (RR=1.16, 95% CI = 0.80–1.69). In sub-analyses, similar significant associations were found when the exposure level was defined by the job title, but not the job-exposure matrix. In addition, significant associations between occupational exposure to ELF-EMF and increased risk of ALS were found in studies of subjects who were clinically diagnosed but not those based on the death certificate. Moderate heterogeneity was observed in all analyses.

Conclusions: Our data suggest a slight but significant ALS risk increase among those with job titles related to relatively high levels of ELF-EMF exposure. Since the magnitude of estimated RR was relatively small, we cannot deny the possibility of potential biases at work. Electrical shocks or other unidentified variables associated with electrical occupations, rather than magnetic-field exposure, may be responsible for the observed associations with ALS.

Image: image4you @ Pixabay

Latest articles

Dawn Lester & David Parker … As we have shown in many...
Dawn Lester & David Parker Modern medicine is widely acclaimed as being...
Dawn Lester & David Parker In parts one and two, we showed...
Dawn Lester & David Parker In the three previous parts of this...
Roger Koops For those who may not recall Chicken Little (AKA Henny...
Tristan Coleman Does the latest ‘climate consensus’ study show a genuine agreement...

Thank you!

Thank you for your membership application. As soon as your payment has been received your membership will be activated and you will be informed via email.

Thank you.

Thank you!

The form has been submitted successfully!