DETERMINATION OF ATRAZINE AND SIMAZINE IN DRINKING AND SURFACE WATERSBY SOLID-PHASE EXTRACTION AND HIGH-PERFORMANCE THIN-LAYER CHROMATOGRAPHY

A simple high-performance thin layer chromatographic (HPTLC) method ha s been developed for the determination of atrazine and simazine herbic ides in drinking and surface waters. The method involves solid-phase e xtraction on C-18 Bakerbond cartridges followed by development of the concentrated extracts on HPTLC silica plates with a nitromethane-tetra chloromethane (1:1, v/v) mobile phase and quantitation by UV scanning densitometry. Using the proposed mobile phase composition, pronounced background suppression on the chromatograms of the real water samples was accomplished. The detection limits of the method were 30 and 60 ng /l for atrazine and simazine, respectively, at the 80-400 ng/l fortifi cation level in the surface waters. The method was successfully applie d to the analyses of tap and surface waters with overall recoveries be tween 58 and 93% and a relative standard deviation below 12%. The resu lts show, that the HPTLC method is sufficiently selective and sensitiv e to be employed in screening of contaminated waters containing the tr iazines below the maximum residues limits of the European Community.