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Abstract: The presence of cyanotoxins in benthic Lyngbya wollei algae samples collected in a fluvial lake along the St. Lawrence River, Canada, was investigated using a multi-toxins method. Hydrophilic interaction liquid chromatography (HILIC) and reverse phased liquid chromatography (RPLC) were coupled to triple quadrupole mass spectrometry (LC-QqQMS) for quantification and to quadrupole-time of flight mass spectrometry (LC-QqTOFMS) for screening and confirmation. The presence of two saxitoxin analogues, LWTX-1 and LWTX-6, was confirmed in benthic Lyngbya wollei algae samples. Concentration of LWTX-1 was between 209±5 and 279±9μgg−1. No other targeted cyanotoxin (such as anatoxin-a, nodularin, microcystin-LR, microcystins-RR and saxitoxin) was found in the samples. The presence of LWTX-6 was observed by using a screening approach based on an in-house database of cyanotoxins, an algorithm of identification and high resolution mass spectrometry measurements on the precursor and product ions. This work demonstrates the need for more research on the fate of benthic cyanotoxins in aquatic ecosystems such the St. Lawrence River. [Copyright &y& Elsevier]

With the consumption of chemotherapy agents, residues of anticancer drugs may be increasingly found in hospital and municipal wastewaters. Quantification of these highly polar micropollutants remains challenging due to poor chromatographic retention on typical reversed phases. This study investigated different solid-phase extraction (SPE) materials for automated on-line preconcentration of complex matrices (hospital and municipal wastewaters) and various chromatographic column options. A hyper crosslinked hydroxylated polystyrene-divinylbenzene copolymer SPE sorbent coupled on-line with hydrophilic interaction liquid chromatography tandem mass spectrometry (HILIC-MS/MS) yielded suitable limits of detection (LOD: 1–2 ng L−1) for 5-fluorouracil (5-FU) and 2',2'-difluorodeoxyuridine (dFdU). Optimization of chromatographic conditions led to a single LC-MS/MS method for the analysis of other cytostatic drugs including cytarabine (CYT), gemcitabine (GEM), methotrexate (MTX), ifosfamide (IFO), cyclophosphamide (CYC) and capecitabine (CAP). The filter membrane for sample pre-treatment, HPLC mobile phase additives, and on-line SPE loading parameters were also investigated. The methods were validated in wastewater matrix with suitable determination coefficients (R2 range: 0.9982–0.9999), LODs (0.5–5 ng L−1), accuracy (78–111%), intraday precision (2.6–12%), and interday precision (2.1–13%). The occurrence of cytostatic drugs was examined in field-collected water samples from hospital effluents and municipal wastewater treatment plants (WWTP) in Canada. CAP (3.7–64 ng L−1), dFdU (6.1–300 ng L−1), and MTX (1.8–68 ng L−1) were frequently detected across both matrix types, while IFO was detected in hospital wastewater (23–140 ng L−1) but not in municipal WWTPs. Image 1 • On-line SPE was successfully coupled with HILIC-MS/MS to analyze water samples. • First on-line workflow for ultra-trace detection of the polar anticancer drug 5-FU. • Combinations of 5 SPE x 12 analytical columns were screened for 8 anticancer drugs. • Two HILIC & RPLC-MS/MS methods presented suitable LODs (0.5–5 ng L−1) in wastewater. • dFdU, CYT, GEM, MTX, IFO, CYC & CAP were detected in hospital & urban wastewaters. [ABSTRACT FROM AUTHOR]