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Triazines and their degradation products are transported to the aquatic environment, and once there, the probability to reach the marine environment is very high. In this paper, solid phase extraction (SPE) and extraction by matrix solid phase dispersion (MSPD) to analyse nine triazines (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine and terbutryn) and eight degradation products (desethylatrazine, desethyldesisopropylatrazine, desethyl-2-hydroxyatrazine, desethylterbuthylazine, desisopropylatrazine, desisopropyl-2-hydroxyatrazine, 2-hydroxyatrazine and 2-hidroxyterbuthylazine) in seawater and marine sediments samples were used. The analysis was carried out using liquid chromatography with tandem mass spectrometry (LC-ESI-MS/MS). The methods were optimized and validated to achieve a selective and sensitive determination of the analytes from different sample, regardless of its complexity. Under the optimum conditions, the proposed methods provided adequate limits of quantification (0.05-0.45 μg L and 0.23-4.26 μg kg in seawater and marine sediments, respectively). Intra- and inter-day relative standard deviation were below 1.41% for all compounds. Recoveries were evaluated, and acceptable values that ranged from 87.5-99.4 and 60.9-99.7% for the seawater and sediment samples, respectively, were obtained. The proposed methods were applied to the analysis of the target compounds in seawater samples and marine sediments from a coastal area of Galicia (NW of Spain).

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A simple method based on solid-phase extraction combined with liquid chromatography for simultaneous determination of nine triazine herbicides (ametryn, atrazine, cyanazine, prometryn, propazine, simazine, simetryn, terbuthylazine, and terbutryn) in surface water samples was developed and validated. Under optimized conditions, 50 mL of water sample was pumped through the Oasis HLB cartridge, and triazines were eluted with 3 mL acetone. Finally the extract was concentrated to dryness, reconstituted with 1 mL methanol : water (1 : 1) and injected into the HPLC-DAD system. The stability of the herbicides on the cartridges at −18 and 4°C was also evaluated, and the recoveries obtained after three weeks of storage were satisfactory for all compounds. The analytical features of the proposed method were satisfactory: repeatability and intermediate precision were <10% and recoveries in spiked river water and seawater samples were higher than 93% for all compounds studied. Limits of quantification (varied from 0.46 to 0.98 µg L−1) were adequately allowing the determination of these compounds at the levels requested by the 2008/105/EC Directive. Finally, this method was applied to the analysis of 50 seawater samples from Galicia (northwest Spain).