Is wifi harmful ? i read on net that it emits rf radiation, which is toxic ? pls advise from research studies.

Not really: Majority of WiFi emissions are in between zero and 300 GHz. The World Health Organization reports that these are the frequencies that are the safest. There have been studies on plant life that have shown harmful effects but a plant cell is very different than a complex human body with billions of cells. There is more data being processed and more testing being done for the upcoming months and years ahead