Radium-226 is a radioactive isotope of the element radium, which is part of the alkaline earth metals group. It is produced naturally from the decay of uranium-238 and has a half-life of about 1,600 years. Radium-226 emits alpha particles and gamma radiation, making it hazardous to human health if ingested or inhaled. Historically, radium-226 was used in various applications, including luminous paints for watches and instrument dials. However, due to its radioactivity and associated health risks, its use has been largely discontinued, and strict regulations now govern its handling and disposal.