SPECIATION OF SELENIUM AND ORGANOTIN COMPOUNDS IN SEWAGE-SLUDGE APPLIED TO LAND

Many studies have been devoted to the fate of heavy metals in waste wa ter treatment plants and their impact on the environment. Some element s, such as selenium and tin, have more complex chemical properties. Th ey can form organic compounds, be metabolized and transformed. Their b ehaviour in sewage treatment works is still almost unknown, although n orms exist on due to their potential high toxicity for living organism s. Our study concerns natural samples from French representative sewag e treatment plants. The analytical methods developed for the speciatio n of Se (phase and species speciation) and Sn (species speciation) in that kind of medium have been checked by the use of two different anal ytical techniques and certified samples from the BCR.