Which radioactive gas is emitted by granite rock formations?

Question: Which radioactive gas is emitted by granite rock formations?

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Granite rock formations are known to emit a radioactive gas called radon. Radon is a colorless, odorless, and tasteless noble gas that is derived from the natural decay of uranium and thorium, both of which are trace elements present in varying amounts in granite. It’s important to note that not all granite emits significant levels of radon, and the emission is influenced by the specific mineral composition of the rock.

When uranium and thorium undergo radioactive decay in the granite, they produce radium, which further decays to produce radon. This gas can move through the microscopic spaces between the rock particles and into the atmosphere. In outdoor settings, radon disperses rapidly and is typically not a health concern. However, in confined spaces like basements or homes built on granite bedrock, radon can accumulate to levels that may pose health risks.

Long-term exposure to elevated levels of radon is known to increase the risk of lung cancer. In fact, radon is the second leading cause of lung cancer after cigarette smoking. Because of its health implications, many countries recommend regular testing for radon, especially in homes, to ensure that levels are not above recommended safety thresholds. If high levels are detected, mitigation measures can be taken to reduce its concentration in indoor environments.