Pollutants Biotransformation

摘要

All living organisms are exposed to large amounts of xenobiotics, many of which may be toxics. The presence of xenobiotics in a living organism can unbalance the living body by inhibiting its growth or interfering with one or more components or chemical reaction on which it is dependent. The sum of the processes by which a xenobiotic (pesticide) is subject to chemical changes in living organisms is named biotransformation. Biotransformation reactions (phase Ⅰ or phase Ⅱ) are important in understanding the metabolism of endogenous molecules (endobiotics), or of the exogenous ones (xenobiotics) and their purpose is to increase the protective mechanisms developed in relation to cells or biological fluids. The equilibrium among the concentration of parent pesticides, biotransformation intermediates and conjugates, is responsible for the cellular, tissue or organism toxicity.