Rapid and sensitive determination of carbaryl, carbofuran and fenobucarb by liquid chromatography with electrochemical detection

A rapid and sensitive procedure is described for the determination of the N-methylcarbamates pesticides, carbaryl, carbofuran and fenobucarb, by liquid chromatography. The pesticides are previously hydrolyzed, in a separate step, to their phenolic derivatives, which, after the separation in a high speed column in a time lower than 2.5 min, are detected in a high sensitivity amperometric cell at a potential of +0.6 V. The method presents detection limits around 0.7 ppb and has been satisfactorily applied to the analysis of these compounds in spiked river water samples.