Evidence of Oxidative Damage in Paraquat Toxicity

The herbicide paraquet (1, 1-dimethyl-4, 4-bipyridilium dichloride; PQ) is a highly toxic quaternary nitrogen herbicide. Many cases of PQ acute poisoning and death have been reported over the past few decades. The mechanisms of PQ toxicity have been reported to involve the generation of reactive oxygen species (ROS) in different organs. Several studies have suggested that the mechanism of PQ toxicity is associated with a redo cyclic reaction, which generates superoxide anion, singlet oxygen and other free radicals, leading to cellular NADPH depletion and lipid per oxidation of cell membranes. Then PQ poisoning is directed towards the use of antioxidants. There are several reports about oxidative stress in acute and chronic exposures to PQ. In this respect, there are several in vitro and in vivo but few clinical studies about mechanism underlying these effects. Bibliographic databases were searched for the years 1960-2013 and resulted in 378 articles. After elimination of duplicates or irrelevant papers, 70 papers were included and reviewed. Results indicated that the status of PQ toxicity and treating the toxic effects produced by PQ is presented. Nonetheless, it is reasonable for the scientific community to provide an expert review and evaluation of this herbicide and their toxic potential to produce disorders in brain, liver, kidney and lung in living organisms.