Selenium contamination in water Selenium contamination is worldwide phenomenon. Contamination of Selenium in surface and ground water in river basins is one of the critical problems now a days. As Selenium shows a narrow tolerance limit (40 400mg day) the problem of both deficiency and toxicity of Se have being identified in many parts of India and the world. Different countries are making efforts to remove Selenium from water using different technologies. Some specific processing technologies include reduction bioremediation phytoremediation coagulation electro coagulation co precipitation electric kinetics adsorption chemical precipitation and membrane technology