Determination of nonylphenol and short-chained nonylphenol ethoxylates in drain water from an agricultural area

Water samples from agricultural drains were tested for the presence of nonylphenol and nonylphenol mono- and diethoxylates. The analytes belong to biodegradation products of long-chained nonylphenol ethoxylates, which are used as additives in pesticide formulations. Quantification of these analytes was performed by HPLC with fluorescence detection after isolation by using multi-capillary polytetrafluoroethylene (PTFE) trap extraction. This newly developed technique allowed obtaining about 90% recovery of these analytes in synthetic samples and several percent lower recovery in real samples. Also, no additional sample cleaning was needed before chromatographic analysis. The limit of quantitation for all the analytes was 0.1 μg L−1. The nonylphenol, nonylphenol mono- and diethoxylates were detected at the concentrations ranging from 0.5 to 6.0 μg L−1, from 0.2 to 0.7 μg L−1 and from below 0.02 to 0.4 μg L−1, respectively. Concentrations of nonylphenol and its derivatives were higher in samples taken in spring than in summer.