Does the EPA believe there is a danger of radon gas or associated radiation being emitted from granite countertops?

It is possible for any granite sample to contain varying concentrations of uranium and other naturally occurring radioactive elements. These elements can emit radiation and produce radon gas, a source of alpha and beta particles and gamma rays. Some granite used for countertops may contribute variably to indoor radon levels. Some types of granite may emit gamma radiation above typical background levels. However, at this time EPA believes that the existing data is insufficient to conclude that the types of granite commonly used in countertops are significantly increasing indoor radon levels. While radiation levels are not typically high, measurement of specific samples may reveal higher than expected levels on a case-by-case basis. Granite is a naturally occurring igneous rock, meaning that it was formed by the cooling of molten rock. It is quarried and processed to produce commercial products such as countertops.  more