Monitoring of N-methylcarbamate pesticides in the Pinios River (central Greece) by HPLC

Abstract

Seasonal variations of N-methylcarbamate pesticides in Pinios River waters of central Greece were determined for a period of one year (January to December 2003). The water samples were collected every month from four sampling sites. Liquid–liquid extraction followed by HPLC was used for the determination of 10 carbamate pesticides. The ranges of the most commonly encountered pesticides in the surface river water were for carbofuran 25–206 ng L−1, aldicarb nd–69 ng L−1, aldicarb sulphoxide 5–107 ng L−1, methomyl nd–86 ng L−1, 3-hydroxycarbofuran nd–117 ng L−1, propoxour nd–91 ng L−1, carbaryl 10–100 ng L−1, and methiocarb 7–117 ng L−1. The higher concentrations in river water were measured during the period of May to October, following seasonal application, and diminished significantly during the autumn and winter. The highest concentrations of the carbamate pesticides were detected in sampling site 2 (Piniada), near an area with intense agricultural activity. This work clearly demonstrates that agricultural practices in the agricultural area of Thessaly have degraded the quality of surface waters. N-methylcarbamate pesticides data obtained in this study were statistically analysed by two-way analysis of variance (ANOVA). It was proved that both seasonal and spatial variations are significant sources for the total variance, the latter making a greater contribution than the former.