What elements make up nuclear waste?

Nuclear waste primarily consists of radioactive isotopes produced during nuclear reactions, including fission products such as cesium-137, strontium-90, and iodine-131. It also contains actinides like uranium, plutonium, and neptunium, which are generated from the fuel used in nuclear reactors. The composition of nuclear waste varies depending on the type of reactor and the fuel cycle, but it generally includes a mix of elements with varying half-lives and radioactive properties. Proper management and disposal of these materials are critical due to their long-term environmental and health risks.