Abstract: Simultaneous determination of malathion and atrazine by HPLC was carried out under the following laboratory conditions: the optimum detecting wave length 220 nm, and mobile phase V(CH3OH)∶V(H2O)=7∶3, which could reach better separating result. The linearity ranges for malathion and atrazine were 0.003 66~1.83 μmol/Land 0.121~60.3 μmol/L, respectively, the linearity correlation coefficients for malathion and atrazine were both more than 0.999 4. The detection limits for the two pesticides were 0.003 66 μmol/L and 0.121 μmol/L, respectively. The RSDs of the method for determining malathion and atrazine were lower than 10%.

Key words: malathion, atrazine, high performance liquid chromatog raphy, aquatic environmental monitoring