Development of an ELISA for the N-dealkylated s-triazines: Application to environmental and biological samples

A sensitive and rugged ELISA for the detection of the N-dealkylated metabolites of atrazine and simazine was developed and applied to environmental and biological samples. The limits of detection were approximately 10 ng ml(-1) for water samples, 40 ng ml(-1) for human urine when analyzed without any sample preparation and approximately 45 ng g(-1) for solvent-extracted soil. This assay was tolerant to changes in pH salt and solvent effects. Comparison of the results from this ELISA with nominal values for a series of tap water samples spiked in a blind fashion resulted in a good correlation coefficient between the values found and those spiked. However, the ELISA systematically underestimated concentrations. Examination of the source of this error revealed that the dealkylated triazine concentrations of the samples declined with time. The assay was used to monitor the presence and loss of dealkylated triazines in a variety of samples. These data indicated that caution must be used in the analysis and interpretation of the presence of these N-dealkylated metabolites.