A method for the routine semiquantitative determination of hydroxy-s-triazines in soils

Abstract

A method is described for the routine, semiquantitative determination of several nonvolatile degradation products of thetriazine 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 hydroxys-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-(isopropylamino)-s-triazine], hydroxy-cyprazine [2-hydroxy-4-(cyclopropylamino)-6-(isopropylamino)-s-triazine] , and cyanazine I11 [2-chloro-4-(l-carboxy-l-methylethylamino)-6-(ethylamino)-s-triazine] could be extracted relatively more efficiently from fortified (37.8-790.0 pg/kg) soil samples than could N-dealkylated 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.The hydroxy-s-triazines are the major degradation products of the chloro-s-triazine herbicides in soil. The determination of the hydroxy degradation products is made difficult by their low solubility in nonacid or nonalkaline solvent systems (Ward and Weber, 1968), strong adsorption to organic matter and clay surfaces of soils (Weber, 1972), and low efficiency of derivatization for gas chromatographic analysis (Cochrane, 1975).

Determination of terbutryn and its degradation products in water, sediments, aquatic plants, and fish

“…HC has similar partitioning behavior to HT between CH2C12 and water, and since cyprazine is not used extensively, it is unlikely to be encountered in untreated pond samples. Actual recoveries of HT ranged from 40 to 60% by LC analysis which was similar to recoveries of hydroxyatrazine from soils found by GLC (after methylation) (Muir and Baker, 1978; Khan et al, 1975). A liquid chromatogram of a fortified sediment extract containing HC, HT, and DEHT is shown in Figure 3.…”

“…Little interference from coextractive peaks was encountered in the analysis of HC, HT, and DEHT in most sediment extracts. The detection limit for HT and DEHT was about 0.05 jug/g (dry weight), which was less sensitive than gas chromatographic procedures (Muir and Baker, 1978; Khan and Marriage, 1977) because of the relatively low sensitivity of the UV absorbance detector to hydroxytriazines at 254 nm.…”

Atrazine and Its Primary Metabolites in Swiss Lakes: Input Characteristics and Long-Term Behavior in the Water Column

“…As can be seen from Table and Figure , in all three lakes, the most abundant metabolite (DEA) occurred at levels similar to those of atrazine, while the two other metabolites were present at 2−4 times lower levels. The new and most interesting result here is the rather low abundance of ATOH, which is considered to be the major atrazine metabolite in soils ( , ). Inspection of Figure further shows that the shape of the cumulative input curves was quite similar for the three metabolites and not very different from that of atrazine.…”

Deethylsimazine: bacterial dechlorination, deamination, and complete degradation

“…CEAT is observed in waters draining from fields that have been treated with chloro-s-triazine herbicides [e.g., Muir and Baker (1976) and Roberts et al (1979)] and is presumed to be a (microbial) metabolic product from, e.g., simazine, in contrast to the nonbiological dechlorination of, e.g., simazine to hydroxysimazine (EEOT) on clay mineral surfaces (Jordan et al, 1970). The N-dealkylation of appropriate chloro-s-triazines to CEAT is also known in plants [e.g., Wichman and Byrnes (1975)l and is widespread in mammalian liver [e.g., Dauterman and Muecke (1974) and Khan et al, (1979)…”