Many detectors are used for determining the radioisotopes and heavy elements present on earth. Some of those detectors or methods that are widely used to determine radioisotopes and heavy elements are high-purity germanium (HPGe) detector, sodium iodide (NaI) detector, Geiger Muller counter, atomic absorption spectrometer (AAS), inductively coupled atomic emissions spectrometer (ICP-AES), inductively coupled plasma mass spectroscopy (ICP-MS). These detectors are very sensitive. Theycan detect even trace elements. Radioactive isotopes and heavy elements that may be present in low concentrations can be detected by these sensitive radiation detectors.