Technical Report from the year 2015 in the subject Physics - Optics, grade: 1, , course: M.TECH, language: English, abstract: As the process of industrialisation evolves, more and more pollutants add to the environment and put the health of the living world at stake. So the necessity to design user-friendly, advanced systems to detect and control these contaminants with high accuracy, sensitivity and stability has gained prime importance. Several conventional instruments are still in use but they have many drawbacks. Optical biosensors can be a suitable alternative to overcome the limitations of the conventional techniques as they are capable of real-time, high frequency monitoring of the pollutants with high accuracy, sensitivity, selectivity and precision. This article discusses about the various types of bio receptors which react to the analytes and how different techniques can be employed for their accurate detection by analysing the interaction of the bio receptors with the contaminants. This article also puts to light the remarkable developments in the field of optical biosensors and bio-recognition elements and their applications in pollution control.