Reproducibility and time needed for measurements of 30 μL samples of Cr(VI) obtained with FAA spectrometer using micro-injection of the effluents as discrete samples. The effluents were obtained after 0.1 mg/mL solutions of 30 μL volumes are simultaneously loaded to the parallel microcolumns to retain the Cr(VI) and then simultaneously eluted the microcolumns with 30 μL methanol.