A simple blood test might be used successfully to predict the chances of a person contracting lung cancer. Researchers at Columbia University, New York, USA, used blood samples that had been collected 13 years ago and found that people whose white blood cells were damaged were at a higher risk of getting cancer. According to the group of researchers, this damage is mainly due to exposure to polycyclic aromatic hydrocarbons (PAH), which binds to the genetic material. The group measured this bound PAH. While tobacco smoking releases PAH, they are also emitted from cars, power plants and during the process of cooking certain food.