Carbamatos sĂŁo os pesticidas mais frequentemente encontrados em alimentos e bebidas de coloração escura em casos de intoxicação acidental ou intencional. Neste trabalho, extração lĂquido-lĂquido com partição em baixa temperatura (LLE-LTP) foi otimizada e validada para determinação dos carbamatos aldicarb, carbofuran e carbaril em bebidas de sucos de uva e leite achocolatado. Este mĂ©todo envolve a extração com acetonitrila, partição lĂquido-lĂquido em baixa temperatura e anĂĄlise por cromatografia lĂquida de alta eficiĂȘncia com detecção ultravioleta (HPLC-UV). O mĂ©todo Ă© rĂĄpido, eficiente e de baixo custo, emprega pequenos volumes de solvente por amostra e nĂŁo necessita de limpeza dos extratos. O mĂ©todo de extração foi seletivo e apresentou porcentagens de extração acima de 90%. As premissas relacionadas com os testes estatĂsticos de linearidade foram verificadas e confirmadas. O mĂ©todo de extração e anĂĄlise foi validado com resultados satisfatĂłrios e pode ser aplicado em anĂĄlises de rotina e forenses.Carbamates are the pesticides most commonly found in dark colored foods and beverages in cases of accidental or intentional poisoning. In this work, the liquid-liquid extraction with low temperature partitioning (LLE-LTP) was optimized and validated for determination of the carbamates aldicarb, carbofuran and carbaryl in grape juice and chocolate milk beverages. This method involved extraction with acetonitrile, liquid-liquid partition at low temperature and the analysis by high performance liquid chromatography with ultraviolet detection (HPLC-UV). The method is rapid, efficient and of low-cost, employing small volumes of solvent per sample and requiring no cleanup of the extracts. The extraction methodology was selective and presented recovery percentages above 90%. The premises related to the statistical linearity tests were checked and confirmed. The method of extraction and analysis was validated with satisfactory results, and may be applied in forensic and routine analysis Keywords: carbamates, low temperature partitioning, high performance liquid chromatography, sample preparation, validation
IntroductionCarbamate insecticides are widely used in gardening and agriculture due to their broad spectrum of activity and relatively short environmental persistence. However, they are potentially toxic to humans, particularly in the context of intentional self-poisoning. 1,2 Carbamates are found as commercialized products for agricultural practices and some compounds of this group, with their respective commercial names are: carbaryl (Sevin Âź ), aldicarb (Temik Âź ) and carbofuran (Furadan Âź ). From these, aldicarb stands out as the main target on the list of controlled pesticides of the United States Environmental Protection Agency (EPA) due to its elevated toxicity to mammals. 3,4 The maximum residue level (MRL) of aldicarb 5,6 and carbofuran 6 in water is 10 and 7 ÎŒg L -1 , respectively. In Goulart et al. 1155 Vol. 23, No. 6, 2012 milk, the MRLs established for aldicarb, 7,8 Exposures may occur accidentally, with ...