Rapid Determination Of Zine B In Soil,Vegetables And Fruits By Colorimetry

Zineb is a kind of typical Ethylenebisdithiocarbamates(EBDCs)fungicides.The simple extraction and residual analysis of zineb in soil,vegetables and fruits were investigated.Firstly,zineb can be degraded to produce CS2 during the co-distillation of the samples of soil,vegetables and fruits with hydrochloric acid stannous chloride.Secondly,CS2 is adsorbed by the diethanol aminesolution of copper to form a yellow complex,which has a maximum absorption at 434 nm in the UV-Vis spectra.Thus,the content of zineb can be determined by colorimetry through the adsorption of the yellow complex.The results showed that the lowest detectable concentration of zineb in soil,vegetables and fruits was 0.011 mg/kg.The recoveries of method were 80.78%~102.88% for soil samples,84.35%~102.77% for vegetables and 80.28%~104.30% for fruits.It can be seen that the method for determination of Zineb in soil,vegetables and fruits by colorimetry is accurate,easy to operate and widely applicable.The method can meet the requirements of the fungicide residue analysis.Additionally,the concentrations of zineb in 105 soils,12 kinds of commercially available vegetables and 10 kinds of fruits were determined with colorimetric method.Through measuring the concentration of zineb in 5 soils with colorimetric method and gas chromatography-mass spectrometry,the results were convinced that colorimetric method was reliable for zineb determination.