Strontium- 90 and radon-222 both pose serious health risks. \(^{90}\) Sr decays by \(\beta\) -particle production and has a relatively long half-life $(28.9 \text { years). Radon-2222 decays by } \alpha \text { -particle production }$ and has a relatively short half-life \((3.82 \text { days). Explain }\) why each decay process poses health risks.

Strontium-90 decays through the process of β-particle production, which involves emitting an electron from the nucleus. As a consequence, radiation is released that can penetrate living tissues, potentially causing cellular damage, disruption of DNA, and an increased risk of developing cancer. Strontium-90 is a bone-seeking radionuclide, meaning it is chemically similar to calcium and gets incorporated into bones when absorbed by a living organism. This makes Strontium-90 particularly dangerous, as its radioactive decay can occur directly in the bone, leading to an increased risk for bone cancer, leukemia, and other bone-related illnesses.

The half-life of Strontium-90 is 28.9 years, which means it remains radioactive for a substantial amount of time. This long half-life poses health risks because it allows strontium-90 ample time to accumulate in the environment and potentially be absorbed by living organisms. Consequently, continuous exposure to the emitted β-particles over an extended period increases the risk of damage to cells and DNA, leading to possible chronic illnesses and cancer.

Radon-222 decays through α-particle production, emitting helium nuclei and releasing radiation. α-particles have a higher ionization potential compared to β-particles, which means they can cause substantial damage when they interact with biological tissues. However, α-particles cannot penetrate deeply into living tissues and can be stopped by outer layers of the skin. The main health risk associated with Radon-222 arises when it is inhaled, as the radiation can directly interact with the sensitive lung tissue, causing cellular damage, DNA disruption, and potentially lung cancer.

The half-life of Radon-222 is 3.82 days, which means it decays relatively quickly. While the rapid decay implies that Radon-222 doesn't persist in the environment for extended periods, it can still pose health risks due to its α-particle emissions. When Radon-222 accumulates in enclosed spaces such as houses and buildings, the continuous radioactive decay can lead to high levels of indoor radiation, significantly increasing the risk of lung cancer due to long-term exposure. In summary, Strontium-90 poses health risks due to its β-particle emission, ability to accumulate in bones, and long half-life leading to prolonged exposure. Radon-222, on the other hand, poses risks through α-particle emission primarily when it is inhaled and accumulates in enclosed spaces. Both radioactive isotopes can cause cellular damage and increase the risk of cancer.