Analytical methods employing liquid chromatography-mass spectrometry (LC-MS-MS) for ametryn determination in river water, river sediment and in freshwater bivalve mussel Corbicula fluminea are described. Liquid-liquid extraction was used for sample preparation. The analyses of ametryn in samples were performed on a reversed-phase RP-18 column with MS detection in positive electrospray and multi reaction monitoring modes. The quantitation limit of ametryn was 20 ng L-1, 0.1 ng g-1 and 0.5 ng g-1, for water, sediment and bivalve samples, respectively. Linearity, precision, accuracy and recovery were also reported. The results obtained for method validation are within the international limits and in accordance with literature, suggesting that the developed methods are suitable for the quantitation of ametryn in river water, river sediment and in bivalve Corbicula fluminea. These methods were applied for the analysis of samples from Mogi-Guaçu River and Pardo River, São Paulo State. Results indicated that the highest level of ametryn was 1.44 ng g-1 in bivalve samples from Mogi-Guaçu River.
ametryn; liquid chromatography; mass spectrometry; method validation; environmental analysis
