Applications of Radioisotopes

Applications of Radioisotopes!

Radioisotopes can be used as environmental tracers to study various aspects of the natural world, including the movement of materials through ecosystems, the age of geological formations, and the behavior of pollutants in the environment. Radioisotopes are unstable forms of elements that emit radiation as they decay into more stable forms. The rate of decay is constant and can be measured with high precision using sensitive detection equipment. This property makes radioisotopes useful as tracers because they can be introduced into a system in a known amount, and their movement and transformation can be tracked over time. Naturally occurring radioisotopes present in our environment have long been used as tracers of various environmental processes. These radionuclides can be classified into two main categories based on their origin i.e cosmogenic and primordial. Cosmogenic nuclides such as 7Be, 14C and 10Be are generated by the nuclear reactions during the interaction between cosmic radiation and stable isotopes present in the atmosphere. For example, 7Be is produced by cosmic ray bombardment of atmospheric nitrogen and oxygen (Fig 1a). Primordial nuclides like 238U, 232Th, 40K have originated during the early stages of formation of the universe and are still present on the earth in significant quantities due to their long half-lives (>108 years) (Fig 1b). 

During the decay of these long-lived nuclides and other daughter nuclides, both stable and radioactive nuclides are formed. The majority of these short-lived natural radioisotope daughters present in our environment come from the uranium and thorium decay series. These short lived radioisotopes act as natural clock and have been widely used to trace environmental processes such as particle scavenging, residence time, water mixing, groundwater age and sedimentation rates. The specific application of such radioisotope in tracing coastal and ocean processes is determined by its half-life (t1/2), source function and other geochemical properties (Ghaleb, 2009) (Fig 2). One common application of radioisotopes as environmental tracers is in hydrology, where isotopes such as tritium and deuterium can be used to study the movement of water through watersheds and aquifers. By analyzing the isotopic composition of water samples taken from different locations and depths, scientists can determine the age, origin, and flow paths of the water. Overall, radioisotopes can be powerful tools for understanding the movement of materials through various environmental processes and for assessing environmental impacts. However, it is important to use them carefully and with appropriate safety measures to avoid potential health and environmental risks.