Diuron concentrations were determined using an Agilent 1100 series HPLC equipped with a diode array detector and C18 column. The operating conditions for diuron were: Apollo C18 cartridge (250 mm × 4.6 mm I.D., 5 μm particle size); isocratic elution at a flow rate of 1.0 mL min−1; injection volume of 20 μL; mobile phase of acetonitrile: water 60: 40; UV detection at a wavelength of 220 nm. The retention time for diuron was noted to be 6.2 min with a minimum detection limit of 0.04 mg L−1.