Since 1994, more than 170 studies on EMF were conducted, many of them funded by manufacturers of wireless communication equipment. About 55% of those studies, however, say that EMF creates blood barriers in the brain. Only one-third of studies supported by the telecommunications industry in the West point to bad effects of EMF but two thirds of studies conducted by independent groups reveal EMF has a long-term health impact. In 1994, a group led by Dr George Carlo, chief scientist of the world's largest research effort into wireless safety, received a $25 mln grant from the telecommunications industry. But in 2001, Dr Carlo published Cellphones: Invisible Hazards in the Wireless Age.