Low-temperature clean-up method for the determination of pyrethroids in milk using gas chromatography with electron capture detection.
This paper describes a new gas-chromatography with electron capture detection (GC-ECD) method for determination of some pyrethroids in milk samples. The extraction of the pyrethroids was carried out by liquid-liquid extraction with clean-up by precipitation at low temperature, without additional stages for removal of fat interferences. The method was efficient with recoveries of 93.0+/-0.1% for cipermethrin and 84.0+/-0.3% for deltamethrin. The quantification limits were 0.75 microg L(-1) for both pyrethroids. The method was simple, of easy execution, and used only small quantities of organic solvent. After optimization and validation, the method was used for the determination of residues of the pyrethroids cipermethrin and deltamethrin in milk and in lactea drink commercialized in Viçosa (MG, Brazil). Some samples presented contamination with deltamethrin at levels below the maximum contamination limits established by the FAO.
Goulart
Simone Machado
SM
Departamento de Química, Universidade Federal de Viçosa, Av. P. H. Rolfs, s/n, 36570-000 Viçosa-MG, Brazil.
de Queiroz
Maria Eliana L R
ME
Neves
Antônio Augusto
AA
de Queiroz
José Humberto
JH
D000818:Animals; D001938:Brazil; D011232:Chemical Precipitation; D002849:Chromatography, Gas / Q000295:instrumentation / Q000379:methods*; D003080:Cold Temperature; D004583:Electrons; D005504:Food Analysis / Q000295:instrumentation / Q000379:methods*; D005506:Food Contamination / Q000032:analysis*; D006801:Humans; D007306:Insecticides / Q000032:analysis*; D008892:Milk / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry; D011722:Pyrethrins / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012997:Solvents / Q000737:chemistry
D007306:Insecticides; D009930:Organic Chemicals; D011722:Pyrethrins; D012997:Solvents