Residues from Endosulfan on fruit and tubers

Abstract

Endosulfan is a pesticide by ester group with sulphurous acid of the chlorinated cyclic dial. For registering purposes with the aim of extending its range of uses for other applications in Brazil, a study of its residues, as well as of its metabolite, endosulfan sulfate, was performed on potato, tomato, orange, papaya, apple, maracuja and strawberry crops, on which it was applied according to good agricultural practices. The methodology employed was the described for Mitchell with modification. It was satisfactory recovery (82,1% to Endosulfan I, 84,4% to Endosulfan II and 91,0% to Endosulfan sulfate, medians of the fortifyed samples). The lower quantification threshold 0,01 mg/kg (ppm) by gas chromatography with electron capture detector. Among the 60 samples analysed, 20 untreated samples (control) and 40 samples for crops treated with Thiodan, emulsionable concentrate with 350 g/l of active ingredient, Endosulfan I was detected in 19 samples (47,5%), Endosulfan II in 21 (52,5%), and Endosulfan sulfate in 17 (42,5%). No residues were detected in the samples of orange and maracujá pulp, as well as in those of potato, whereas in the papaya pulp samples only the metabolite, endosulfan sulfate, was detected. The highest levels of Endosulfan I, Endosulfan II and Endosulfan sulfate were those detected in orange peel samples, with a total amount reaching the 0.48 and 0.69 mg/kg levels. In the apple, tomato and strawberry samples, the detected values were comparatively low, all of them remaining inside the range for maximum residue limits (MRL) according to Codex Alimentarius.