There is no clear scientific evidence to show that exposure to the electromagnetic fields (EMFs) associated with electric power supplies can cause Parkinson's or Alzheimer's disease. In contrast, there is some evidence that people in electrical industries have an increased risk of developing amyotrophic lateral sclerosis (ALS). However, this increased risk is not necessarily related to exposure to EMFs. It could be due to the increased risk of workers experiencing significant electric shocks during their lives.

The Advisory Group on Non-Ionising Radiation (AGNIR) has recently published its report on ELF Electromagnetic Fields and Neurodegenerative Disease (Doc. NRPB 12 (4) 3–24 (2001)). Most of the research done on possible health effects of exposure to electromagnetic fields and radiation has concentrated on cancer risks. More recently, research on other possible health effects has been carried out, and epidemiological studies have considered the possibility of an association between occupational exposure to EMF and the development of neurodegenerative diseases.

The AGNIR report reviews the evidence for a link between EMF exposure and neurodegenerative diseases. It examines the biological bases for these diseases and epidemiological studies of possible associations between such diseases and work in electrical industries. The role of oxidative stress on ageing of neurons and on calcium exchange in nervous tissues is also reviewed.

The conclusion of AGNIR is that:

There is no good ground for thinking that extremely low frequency electromagnetic fields can cause Parkinson's and only very weak evidence to suggest that they could cause Alzheimer's disease. The evidence that people employed in electrical occupations have an increased risk of developing amyotrophic lateral sclerosis is substantially stronger, but this could be because they run an increased risk of having an electric shock rather than any effect of long-term exposure to the fields per se.

AGNIR also makes recommendations for further work. In particular, it suggests case control studies should be undertaken to examine possible associations of neurodegenerative disease with employment in electrical occupations (with special reference to the occurrence of severe electric shocks) and also with medical treatment with electro convulsive therapy. In addition, clinical and experimental studies using magnetic stimulation of brain tissues should be carried out. The main conclusions and recommendations are available on the NRPB website www.nrpb.org.uk.