Aldicarb residues in Valência and Natal oranges determined by gas chromatography

Abstract

Aldicarb residues in Valência and Natal oranges were determined by gas chromatography in the State of São Paulo, Brazil. The insecticide was applied at the dosages 20 and 40 g of a.i./tree. Samples were collected at 11, 21, 30, 34, 60 and 79 days after application for Valência, and at 10, 20, 31 and 42 days for Natal oranges. Total aldicarb residues were analyzed as the sulfone metabolite. The residues were only detected in Valência oranges in 60 day samples: 0.03 ppm (one sample) and varying from 0.024 ppm to 0.044 ppm for the dosages of 20 and 40 g of a.i./tree, respectively. They were found in Natal oranges in all samples, varying from 0.029 ppm to 0.062 ppm and from 0.042 ppm to 0.159 ppm for the dosages of 20 and 409 of a.i./tree. The residues did not reach the official tolerance limit (0.2 ppm) in any sample.