METHOD FOR ROUTINE SEMI-QUANTITATIVE DETERMINATION OF HYDROXY-S-TRIAZINES IN SOILS

A method is described for the routine, semiquantitative determination of several nonvolatile degradation products of the triazine herbicides atrazine, cyanazine, and cyprazine in soil samples. The procedure involves the extraction of soil samples with aqueous methanol and with a methanol-hydrochloric acid mixture and the partition of the chloro-s-triazines into ethyl acetate. The aqueous extract which contained the hydroxy-s-triazines was cleaned up by use of a column of cationic exchange resin; the hydroxy-s-triazines were converted to their methoxy derivatives by methylation with diazomethane. Gas chromatographic analysis was carried out by use of a Hall electrolytic conductivity detector (nitrogen mode). Recovery studies indicated that hydroxy-atrazine [2-hydroxy-4-(ethylamino)-6-(isopropyl-amino)-s-triazine], hydroxy-cyprazine [2-hydroxy-4-(cyclopropylamino)-6-(isopropylamino)-s-triazine], and cyanazine III [2-chloro-4-(l-carboxy-l-methylethylamino)-6-(ethylamino)-s-triazine] could be extracted relatively more efficiently from fortified (37.8-790.0 μg/kg) soil samples than could N-de-alkylated hydroxy-s-triazines. Overall recoveries of the hydroxy-s-triazines from soil were reduced by the poor efficiency of methylation to the corresponding methoxy-s-triazines. © 1978, American Chemical Society. All rights reserved.