England's Health Protection Agency will study Wi-Fi's effects: The group backs previous statements made that further study would be prudent by planning a comprehensive health study. However, the agency's head notes that, "There is no scientific evidence to date that WiFi and WLANs adversely affect the health of the general population." The study will look into what the actual exposure rates are and provide a firm scientific footing on health effects focused on Wi-Fi. Most studies look at mobile telephone and cell tower/mobile mast outputs.
I contacted the HPA press officer to find out the timeframe of the study, and was told that the estimate was roughly two years.