Rat poison. Lighter fluid. Battery acid. Pesticides. And now...radiation. What do they all have in common? They're all rolled into one cancer causing cigarette. What's worse, tobacco companies have known that radiation was inside cigarettes but hid evidence of it for 4 decades.
The radioactive substance found in cigarettes is polonium-210, a radioactive material that "emits hazardous particles called alpha particles". Whens smokers inhale, the particles work with the other carcinogens found in cigarettes to pull double duty in damaging the lungs (and creating cancer).
ABC News reports that researchers at UCLA recently discovered that tobacco companies knew of radiation in cigarettes as far back as 1959. In 1960, the tobacco companies studied polonium, figured how much radiation a normal smoker would inhale over 20 years, knew it would cause cancer but nefariously hid their calculations so no one would find out. They did their research, knew it was bad and covered their tracks.
Later on, the tobacco companies even ignored new procedures like "acid washing" that would have removed 99% of the polonium-210 from cigarettes. Their reason for not using it? The process would have reduced the "instant nicotine rush" smokers crave. If healthier means less addictive, tobacco companies will never let it happen.