A report from Bad Science Watch, an independent non-profit consumer protection watchdog and science advocacy group in Canada, found that claims of health problems associated with Wi-Fi and electromagentic fields (EMFs) are not supported by science, and often promoted by "fear mongering" activists.
From their report:
Many activists blame Wi-Fi networks' low level radio signals for a broad variety of medical problems, from mild headaches and fatigue to chest pain and heart palpitations, claiming those who suffer from them have ‘Electromagnetic-Hypersensitivity,' or EHS. These claims are not substantiated by the scientific literature and have little acceptance from medical professionals and the scientific community. This activism therefore amounts to nothing more than fear-mongering by misguided special interest groups who are attempting to have these networks removed... As a result many school boards, libraries, and town councils across Canada have been called on by concerned citizens to limit or remove Wi-Fi networks.
Jamie Williams, Executive Director of Bad Science Watch, noted that "Some of the most prominent anti-WiFi scaremongers are tied to the sale and promotion of bogus products to ‘block' Wi-Fi."
Indeed, there is a burgeoning market for so-called "EMF shields" that can be inserted into cell phones that allegedly block harmful electromagnetic waves (though consumer groups say there's no evidence they are effective).
The report notes that the fear mongering surrounding Wi-Fi is not just an academic matter but has real consequences for the public: "Those who stand to suffer from these efforts the most are students (especially from low-income families) who rely on wireless networks for access to the Internet and education resources, and taxpayers who will have to pay for the expensive reversion to wired networks. In addition, families are being been misled into believing that their children are suffering from EHS and may miss an opportunity for early diagnosis of real and serious health problems in their children."
Last year an Albuquerque, New Mexico, anti-WiFi activist named Arthur Firstenberg sued his neighbor claiming that her use of wireless devices including her cell phone and computer caused health problems including hip pain and heart damage. According to an Albuquerque Journal story, District Judge Sarah Singleton ruled that scientific evidence does not support electromagnetic sensitivity.
In her ruling, the judge stated, "Studies have failed to provide clear support for a causal relationship between electromagnetic fields and complaints of EMS."
Singleton relied extensively on the position of the World Health Organization, which concluded that "well controlled and conducted double-blind studies have shown that symptoms do not seem to be correlated with EMF exposure... these symptoms may be due to pre-existing psychiatric conditions as well as stress reactions as a result of worrying about believed EMF health effects, rather than EMF exposure."
Determining whether or not Wi-Fi and EMFs have an immediate effect on health - as Firstenberg claimed - should be very simple using a blinded scientific testing protocol: the Wi-Fi would be randomly turned on or off (unbeknownst to Firstenberg), and he would state whether or not he had hip pain; either the pain appears when the WiFi is on, or it does not.
Unfortunately for Firstenberg the judge found that he could not reliably tell when the Wi-Fi was on and "cannot discern or discriminate the effects of anxiety caused by a testing situation or the presence of electromagnetic stimulus." The case was dismissed.
Concern over the effects of EMFs (via power lines) have been around since the 1970s, and resurfaced in the past 10 years as cell phones have become ubiquitous. Though there's little evidence that they pose a health threat, many people remain concerned. However that fear has done little to stem the popularity of those products.
Typically when the public is concerned about the safety of a product, they reduce (or completely stop) their use of it - for example when fears of bovine spongiform encephalopathy hit Great Britain, beef consumption more or less stopped. However cell phones and Wi-Fi are an exception. While many people claim to be concerned about the technology, few are willing to give up the convenience of the devices.