True or False: Lung cancer risks exist with radon exposures below 4 pCi/L.

The assertion that lung cancer risks exist with radon exposures below 4 pCi/L is indeed recognized in scientific research. While the Environmental Protection Agency (EPA) has set 4 pCi/L as the action level for radon exposure, studies indicate that there is no completely safe level of radon, meaning that even at lower concentrations, there may still be an increased risk of developing lung cancer over time.

The risk is generally understood to be cumulative—meaning that prolonged exposure to radon, even at low levels, can contribute to the overall risk of lung cancer, particularly in certain populations. This includes individuals with other risk factors, such as smoking, which exacerbate the effects of radon exposure.

This recognition of risk at levels below the action guideline is part of a broader understanding within public health and safety. As such, the answer being true reflects the current body of knowledge concerning radon levels and lung cancer risk.