Iron(III) photo-induced degradation of isoproturon: correlation between degradation and toxicity

The degradation of isoproturon photoinduced by Fe(III) was investigated under both artificial and solar light. The monomeric species Fe(OH)21 present under the experimental conditions ([Fe(III)] = 3 x 10(-4)M) is the main Fe(III) species responsible for the degradation of isoproturon. The process involves the attack on the pollutant by (OH)-O-. radicals generated by irradiation of Fe(OH)2(+). The major primary photoproducts were identified; they accumulate in the solution medium before being degraded. The toxicity of the solution to marine bacterium Vibrio fisheri (Beijerinck) Lehmann & Neumann was monitored during the degradation process. It increased in the early stages of the reaction and, among the photoproducts, the N-formyl derivative appeared to be the major product responsible for the increase in toxicity. (C) 2002 Society of Chemical Industry.