A number of international scientists have published a report that raises concerns about mobile phone usage and brain tumors. According to the study, there is a 400% increased risk for teenage cell phone users.

The International Electromagnetic Field group has published a 37-page report saying that there is a risk for teenagers who use mobile phone to develop brain cancer. The group says that children who use mobile phones are especially at risk.

"Some countries are already banning cell phones over health concerns, with France saying children in elementary schools can only use them for texting," said the report's author, Lloyd Morgan in an interview with PC World.

The group has issued an eight-step method to reduce exposure to cell phone radiation for adults and children. The steps include using a wired headset on a call and not a wireless headset, sending messages by texting, keeping the phone away from the body and avoiding use in a moving vehicle.

In the same time, John Walls, vice president of public affairs for the CTIA which represents wireless carriers and handset makers in the US said in a statement that scientific evidence indicates that wireless devices do not pose a public health risk. In addition he says that the American Cancer Society, the National Cancer Institute, the World Health Organizaton and the US Food and Drug Administration say that wireless devices are not a public health risk.