Researchers have recently uncovered a quiet cancer catalyst lurking in plain view within the majority of American households, often unbeknownst to families. A recent study by the American Cancer Society and EPA has connected prolonged exposure to indoor radon with a significant increase in lung cancer rates among non-smokers. Radon is a colorless, odorless radioactive gas that rises from the earth and infiltrates basements and ground-level areas. The CDC estimates that radon is responsible for approximately 21,000 lung cancer fatalities annually in the US, making it the second leading cause after smoking. Here’s how to check your home for under $30.