title: Photochemical behavior of parathion in the presence of humic acids from different origins.
abstract: This paper reports the effect of ultraviolet radiation on the degradation of pesticide ethyl parathion in the presence of humic acids. Ethyl parathion was completely degraded in 300 min using an artificial lamp of 7.41 x 10(-10) einstein/s. Humic acid from peat did not influence the photochemical rate (k = 8.92 x 10(-3) min). However, in the presence of aquatic humic acid, the photochemical rate was higher (11.5 x 10(-3) min). The analytical determinations show the presence of p-nitrophenol and aminophenol in the reaction medium during the photochemical experiments. The kinetic of degradation in all experiments obeyed a first-order reaction pattern.
authors.affiliation: University of São Paulo, Institute of Chemistry of São Carlos, 13560-970 São Carlos SP, Brazil.
authors.forename: Francismário F
authors.initials: FF
authors.lastname: Santos
authors.forename: Ladislau
authors.initials: L
authors.lastname: Martin-Neto
authors.forename: Flavia Pereira Silva
authors.initials: FP
authors.lastname: Airoldi
authors.forename: Maria O O
authors.initials: MO
authors.lastname: Rezende
mesh_terms: D001673:Biodegradation, Environmental; D006801:Humans; D006812:Humic Substances; D007306:Insecticides / Q000737:chemistry*; D010278:Parathion / Q000737:chemistry*; D014466:Ultraviolet Rays
chemical_list: D006812:Humic Substances; D007306:Insecticides; D010278:Parathion