This research demonstrates the quick guthion monitoring with the help of a sensitive method called fast Fourier transformation continuous cyclic voltammetry (FFTCV). Fortunately, FFTCV illustrates the benefits of precision, determination speed, cost-effectiveness, accuracy and simplicity, in comparison with formerly reported techniques. In particular, this method was applied to a gold microelectrode in flowing solutions to detect the guthion concentration in its formulations. The effects of several parameters were examined regarding the sensitivity of the method. After a series of experiments, the detection limit of the method was found to be equal to 1.27 pg/mL, when the optimum conditions were imposed, which is a scan rate value of 40 V/s, an accumulation time of 0.4 s, an accumulation potential of 0 mV and a pH value of 2. During the measurements performance, the integration range of currents included all the potential scan ranges, even the oxidation and reduction of the An surface electrode, for the achievement of a sensitive determination. Then, the potential waveform, consisting of the potential steps for cleaning, accumulation and the step for the potential ramp, was applied to an An disk microelectrode in a continuous way. It is also import ant to refer to the positive points, presented only by the use of this technique. Firstly, it is no longer necessary to remove the oxygen from the test solution. Furthermore, the quick determination of any such compound in many chromatographic methods is possible. Thirdly, the corresponding detection limit is of nanomolar level. (C) 2006 Elsevier B.V. All rights reserved.