| Phenylurea herbicide belongs to an important class of contact herbicides that have been used for pre- and post-emergence control of annual grass, and many broad leaf weeds in many crops acting by inhibition of photosynthesis. Due to low solubility and chemical stability of phenylures, they penetrate slowly through soil and contaminate underground sources of drinking water. Degradation products and metabolites of pesticides in environment can be monitored by means of analysis. Chemical treatment of the polluted water can eliminate harmful and toxic compounds from the water and improve the water resource quality.In this paper the main physico-chemical, toxicological, and environmental properties of phenylurea herbicide were summarized. Analytical methods of residues of phenylurea herbicides in water and crops samples, employed after 1996 were reviewed. Provided the information about liquid-liquid and solid-phase extraction of the samples and clean-up steps. The application of gas chromatography, liquid chromatography, capillary electrophoresis in the analysis of these compounds was exposed in tabular form and commented on. The advantages and drawbacks of the analytical methods developed recently were discussed. At present, the mostly analysis method of residual phenylurea in environment was HPLC.A study of 14 phenylurea herbicides showed a high correlation (R=0.959,S=:0.18 )of their aqueous solubility (logSw.) with their molecular connectivity indexes (MCI) and octanol-water partition coefficients(logKOw), making possible the prediction of the logSw of phenylurea herbicides on the basis of MCI and logKow.A HPLC method for the simultaneous determination of isoproturon and its metabolite, 4-isopropylaniline, in soil was developed. Soil samples were ultrasonically extracted using acetonitril as the extraction solvent. On a 4.6×150mm Eclipse XDB-C18 column, the optimized chromatographic conditions was as follow: mobile phase was acetonitrile: water=70:30 (V/V) , flow rate 0.3 mL/min ,wavelength of detection 245 nm. For isoproturon and 4-isopropylaniline, the linear range of working curve was 0.0250200mg/mL. linear correlation were 0.9946 and 0.9976, the detection limits 4.2 × 10-5mg/mL and 4.5×10-4 mg/mL, the average recovery rate 100.9% and 98.9%, the relative standard deviations 0.66%and 0.67%, respectively.A method of dual-wavelength spectrophotometry was developed for the determination of isoproturon and 4-isopropylaniline in soil. Soil samples were ultrasonically extracted using ethanol as the extraction solvent. The experimental results showed that concentration range of isoproturon was 1.60-11.20mg/L, 4-isopropylaniline was from 1.60 to 14.40mg/L. The absorptions of the two substances at 240nm and 298nm were totally fitted by Beer's Law. The recovery proportions of isoproturon and 4-isopropylaniline in the soil were 104.06-110.63% and 90.00-94.68%, the relative deviations were 3.08-5.08%and 2.54-3.22%,respectively.Advanced oxidation processes (AOPs) are very promising in the water treatment and have received increasing attentions. This paper was the first one to systematical study the degradation of diuron by UV/H2O2. Using a low voltage mercury lamp, the photolysis of diuron in solution was studied. It was showed that diuron was remarkably decomposed under the condition of the experiment. The degradation process follows a pseudo-first-order kinetic. Adding 30% H2O2 0.6%, 2.7mg/L diuron liquor and pH=3, the rate constant was -0.0115min '. Lighting for 340min, the max degradation rate reached to98.8%. The influence of initial concentrations of H2O2 and diuron, pH, HCO3", NO3", CY, SO42" were studied.
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