July 20, 2006, 2:19 PM — First, children living near power lines were believed to be at risk for leukemia. Then, cell phones were going to fry our brains. Now, should we worry about Wi-Fi hotzones?
Prompted by citizen concerns, the Toronto Board of Health is conducting a study of the potential health risks posed by Toronto Hydro Telecom's plans to blanket the downtown core with Wi-Fi access points.
A meta-study of the research done in this area is under way, but no field research is planned, says Ronald MacFarlane, supervisor of environmental health assessment and policy at Toronto Public Health (TPH), which delivers programs and services determined by the Toronto Board of Health.
In 1999, TPH conducted a health assessment of human exposure to RF, and the objective of this second study is to provide an update.
"When cell phones were becoming popular in 1999, councilors responded to concerns in their wards and asked us to look into cell phone towers and antennae," he says. "Similarly, people are now concerned about Wi-Fi initiatives, and we've been asked to look into this so we can come back to council with our assessment."
Based on the recommendations of the first study, the Toronto Board of Health adopted a policy of 'prudent avoidance' in 1999 and determined that the level of exposure to radio frequency (RF) electromagnetic fields should be set at 100 times below Safety Code 6, a guideline developed by Health Canada.
"At this point, we're trying to determine if there's a conflict between prudent avoidance policy and actual usage of Wi-Fi," says MacFarlane. "The initial indications are that Toronto Hydro's Wi-Fi RF would be below our recommended level, and there would be no need to alter plans to meet the standard."
He expects the study and its recommendations to be completed and presented to council in early 2007.
To put the issue in perspective, MacFarlane explains that all manner of infrastructure and consumer devices -- power lines, radio towers, Wi-Fi routers, cell phones, radio and television, and so on -- emit electromagnetic radiation at different frequencies, with varying effects on biological systems.
The electromagnetic spectrum is divided into two major categories, ionizing and non-ionizing radiation.
High-frequency radiation with shorter waves at the ionizing end of the spectrum, such as X-rays and gamma rays, has undisputed detrimental effects on human health. At the borderline between ionizing and non-ionizing is ultraviolet radiation, emitted by the sun, which also has a clear link to skin cancer.