The role of the light on the transformation of pesticides in water depends on many parameters. Transformation are categorized as being direct or indirect photodegradation. We investigated the influence of the spectroscopic properties of pesticides and their effects on the nature of the photochemical reactions with the oxygen species, adjuvants of formulation, humic acids, and water. Chemical reactions, especially elimination, substitution and hydrolysis, are generally accelerated by light, while other spécific reactions such as photo-Fries rearrangement are initiated by it. With organo-halogenated pesticides singlet or triplet states are involved in the scission of the carbon-chlorine bond, while the triplet state is often the first step for the reaction of the other pesticides. In this paper some reactions are presented to illustrate these two types of mechanisms.
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- Phototransformation of Pesticides in Aqueous Solution
- Springer Berlin Heidelberg