Electromagnetic fields (EMF) and health issues

Electromagnetic fields (EMF) are generated near power lines, mobile phones, mobile phone towers, broadcast towers and similar transmitters. Whether EMF can harm human health remains a controversial issue. One source that has received significant media attention is the high-voltage power line.

The scientific debate#

Various studies have investigated whether there is a causal link between power lines and cancers such as leukemia. Some researchers argue that the EMF generated by power lines has frequencies too low to influence living cells or damage DNA.

Other researchers disagree. They suggest that EMF from power lines can cause meaningful changes in a biological system through electric fields induced in the body. To address this concern, scientific standards have been developed to limit public exposure to power-frequency EMF, keeping induced currents below those that occur naturally in the body.

Early research#

In the late 1970s, researchers investigating childhood leukemia reported an association between certain high-current electrical wiring configurations near the home and an increased risk of childhood cancer (Wertheimer and Leeper). This early work, however, did not measure electromagnetic fields directly. Instead, it relied on distances from power lines and the type of wiring.

Since then, researchers around the world have studied power lines. To date, serious limitations have been identified in nearly all of these studies, and it has not been possible to confirm whether a real association exists between EMF and cancer.

What major reviews have found#

An independent scientific review found some evidence that EMF exposures higher than 0.4 microtesla (µT) are associated with a doubling of the risk of leukemia in children. The same review found no evidence of any increased risk of cancer in adults.

The reviewers were careful to explain that no causal link was established and recommended that further studies are needed. The evidence was considered inconclusive because the key studies might have been affected by selection bias or random variation.

Despite the suggestion of an increased risk of leukemia in children exposed to more than 0.4 µT, a range of experimental studies have failed to provide clear supporting evidence that EMF is harmful to health. In particular:

• There is no clear evidence that EMF affects biological processes.
• There is no evidence that EMF can change living cells or is genotoxic (harmful to DNA).
• There is no convincing evidence from animal studies that EMF increases the risk of cancer.

Current guidance#

Health authorities generally support the view that current guidelines on EMF and power lines are adequate, since the EMF generated by power lines is well below the recommended maximum exposure limit. Even so, where it is practical to do so, it is sensible to avoid heavy exposure.

Key points#

• EMF is produced near power lines, mobile phones, towers and similar transmitters.
• Whether EMF harms human health is still debated, and no causal link with cancer has been confirmed.
• Some reviews suggest a possible association with childhood leukemia, but the evidence is inconclusive.
• Current exposure guidelines are considered adequate, though avoiding heavy exposure where practical is sensible.

Where to get help#