Radon is an invisible and odorless gas that is found in the earth, rock, well-water and building materials. It has been linked to an increased risk of lung cancer in humans. After irradiating thousands of cells, the investigators found that cells hit by eight alpha particles showed a mutation rate that was threefold higher than normal. Hei explained that these mutations are different from those caused by irradiating a cell nucleus which causes damage in large sections of the DNA and typically kills the entire cell. When radiation strikes the cytoplasm, the damage is smaller.
Fewer cells are killed, thus there is a greater risk that abnormal cells can divide and spur cancer.
Cytoplasmic irradiation may play a significant role in causing cancer, researchers concluded.