Academic and toxicologist Devra Davis said that the mobile phones could be giving us brain cancer.

According to Davis, an eminent American scientist and one of the country's leading epidemiologists, the mobile phone industry spent years trying to bury scientific evidence -- that it harms -- to protect its $3 trillion, 4.6 billion-customer global business.

With mobile phone use soaring, especially among the young, Davis says a "global public health catastrophe" will be seen in as little as three years if the problem is ignored, the Daily Mail reported.

The most troubling research, she says, threatens male fertility. Research in seven countries, including the US, China and Australia, suggests that keeping a switched-on mobile phone in a trouser pocket can have a drastic effect on sperm count.

"All the research shows the same thing - if you take young men who are trying to become fathers, those who use mobile phones at least four hours a day have about half the sperm count of others," Davis says.

"Sperm exposed to mobile phone radiation in the lab is sicker, thinner and less capable of swimming," she adds.

Mobile phones are low-powered radio frequency transmitters which produce microwave radiation.

In a new book provocatively titled "Disconnect: The Truth About Cell Phone Radiation, What The Industry Has Done To Hide It And How To Protect Your Family," Davis says the threat from mobile phone radiation has been underplayed for too long.

"Is it possible that the pervasive use of mobile phones is causing a host of subtle, chronic health problems, damaging our ability to have healthy children and creating long-term risks to our brains and bodies," she asks.

Her work includes supporting research from studies in the US, Sweden, Greece, France and Russia.

For example, a team at the University Of Washington found that just two hours of mobile phone-level radiation splintered the DNA of brain cells in rats, making them similar to cells found in malignant tumours.

Davis, who is a grandmother, is worried about the effect on children, arguing that their thin, pliant skulls make them more vulnerable.