Photochemical behavior of parathion in the presence of humic acids from different origins.
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.
Santos
Francismário F
FF
University of São Paulo, Institute of Chemistry of São Carlos, 13560-970 São Carlos SP, Brazil.
Martin-Neto
Ladislau
L
Airoldi
Flavia Pereira Silva
FP
Rezende
Maria O O
MO
D001673:Biodegradation, Environmental; D006801:Humans; D006812:Humic Substances; D007306:Insecticides / Q000737:chemistry*; D010278:Parathion / Q000737:chemistry*; D014466:Ultraviolet Rays
D006812:Humic Substances; D007306:Insecticides; D010278:Parathion