The EPA says toxic chemicals in tobacco smoke are the main reason cigarettes cause cancer, but radiation also may play a part.
Fertilizers that tobacco farmers use to increase the size of their tobacco crops contain the naturally-occurring radionuclide radium.
The EPA explained, “As the plant grows, the radon from fertilizer, along with naturally-occurring radon in surrounding soil and rocks, transfer into and on the plant and are later included in tobacco products made from these plants.”
Radon’s decay product, polonium-210, carries the most risk.
One in five deaths each year in the United States are from tobacco use or secondhand smoke exposure—that’s around 480,000 people annually or 1,300 people every day.