Determination of Metham and Thiram in Soils and Vegetables Grown in Greenhouses

摘要

The spectrophotometric method for determining dithiocarbamates based on evolution of carbon disulphide and the formation of coloured complexes with Cu(II) is reviewed and improved for microquantities of Thiram and Metham. The method is applied to the determination of Metham and Thiram in soil samples in order to study the mobility of Metham in soils and the degradation of Thiram in beans and watermelons grown in greenhouses. The t1/2values of Thiram in green beans and watermelons are 10.6 and 12.2 days, respectively.