Superheavy elements, starting from element 104 (Rutherfordium), are all radioactive with very short half-lives, making them unstable and impractical for most applications. They are costly to produce and lack significant practical uses due to their high radioactivity. The actinide series, which includes these elements, features isotopes like Th-232 and U-238 that have long half-lives, unlike the superheavy elements. Misuse of superheavy elements can lead to radiation exposure due to their instability. Overall, the primary drawbacks of superheavy elements are their radioactivity, short lifespan, and high production costs.