Determination of Maneb residues, in tomatoes, by spectrophotometric methodof acid hydrolysis, through multivariate calibration

In this work, a chemometric method was applied through multivariate calibra tion, PLS (Partial Least Squares), to establish the analysis of ethylenebis dithiocarbamates residues in tomatoes samples by the hydrolysis method. The algorithm used to implement the PLS in the MatLab environment on IBM-compa tible personal computer, was obtained from chemometrics package PLS_ToolBox . In samples with elevated levels of Maneb the univariate calibration showe d similar results to the multivariate calibration. However, in samples with lower levels of residues increases occurred in the order of 15 to 47% in t he levels detected by the multivariate calibration. In addition, there was a significant decrease in the standard deviations, in relation to those obt ained when the method of univariate calibration was used. The levels of con tamination by Maneb found in tomatoes samples were below the maximum establ ished by the Brazilian legislation.