RESUMO
An efficient analytical method is described for the analysis of dicofol residues in pulp and orange peel. Samples are mixed with Celite and transferred to chromatographic columns prepacked with silica gel. Dicofol is eluted with ethyl acetate, and the extracts are analyzed by gas chromatography with electron capture detection. Mean recoveries for dicofol at levels of 0.5, 2.0, 5.0, and 10 mg/kg ranged from 87 to 95% with relative standard deviation values between 2.6 and 9.0%. To investigate the effect of a pilot washing system on dicofol residues in oranges, the analytical procedure was applied to samples submitted to different treatments with commercial formulations under field and laboratory conditions. The orange samples with and without washing were analyzed in duplicate, and the results indicated that washing under the described conditions did not allow a complete removal of dicofol residues from orange peel.
Assuntos
Citrus/química , Dicofol/análise , Manipulação de Alimentos/métodos , Inseticidas/análiseAssuntos
DDT/sangue , Hexaclorocicloexano/sangue , Inseticidas/sangue , Exposição Ocupacional , Resíduos de Praguicidas/sangue , Adulto , Idoso , Animais , Brasil , Cromatografia Gasosa , Diclorodifenil Dicloroetileno/sangue , Feminino , Humanos , Controle de Insetos , Malária/prevenção & controle , Masculino , Pessoa de Meia-IdadeRESUMO
A small-scale method was developed for the simultaneous determination of gamma-HCH, heptachlor, aldrin, dicofol, mirex, endosulfan I, endosulfan II and endosulfan sulphate in soil. The extraction and clean-up steps were combined into one step by transferring soil samples to chromatographic columns prepacked with neutral alumina. The pesticides elution was processed with n-hexane : dichloromethane (7 : 3) and the concentrated eluate was analysed using gas-liquid chromatography with electron capture detection. Analyses of the "in vitro" fortified samples with the selected pesticides were performed at three different levels. Mean recoveries for aldrin, gamma-HCH and heptachlor, at levels of 2, 10 and 20 ng/g, ranged from 71 to 87%; for dicofol, at levels of 8, 40 and 80 ng/g, ranged from 97 to 103%; for endosulfan I and II, at levels of 5, 25 and 50 ng/g, ranged from 88 to 96%; for mirex, at levels of 6, 30 and 60 ng/g, ranged from 86 to 110%; and for endosulfan sulphate, at levels of 15, 75 and 150 ng/g, ranged from 93 to 104%. The method can be used for rapid determination of these pesticides in soil.
RESUMO
A method for the determination of six organochlorine pesticides in human serum is proposed. Serum samples containing in vitro spiked pesticides (alpha-HCH, beta-HCH, gamma-HCH, p,p'-DDE, o,p'-DDT, and p,p'-DDT) were used to evaluate the method. The method involved pesticide extraction from a serum-silica suspension with n-hexane-acetone (9:1), extract purification using alumina-column chromatography, and analysis of the final extract using gas-liquid chromatography with electron-capture detection. Mean recoveries for the pesticides spiked from 1 to 7.5 ng/mL ranged from 82 to 97%; for those spiked from 4 to 30 ng/mL, recoveries ranged from 85 to 99%; and for those spiked from 20 to 150 ng/mL, recoveries ranged from 80 to 87%. The method is simple and rapid, requires a minimum of reagents and solvents, and provides high recovery values.