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Highlights • A fast analysis of 14 EPA-priority endocrine disruptors was validated in water. • On-line pre-concentration and LC–MS/MS conditions were carefully optimized. • The total analysis time was <16 min with LOD at sub part-per-trillion levels. • Quantification performances were compliant with EPA method 539.1 requirements. • Method demonstration to real drinking water, surface water, and wastewater samples. Abstract The list of endocrine disrupting compounds (EDCs) defined under U.S. EPA Method 539 was recently expanded to include additional hormones and bisphenol A (BPA). Here, we validated a fast and robust alternative method compliant with Method 539.1 requirements in diverse water matrixes (i.e., ultra-pure water, tap water, surface water, and wastewater influent and effluent). Automated large volume injection solid phase extraction (SPE) coupled on-line to ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was investigated for this purpose. The surveyed molecules included 13 EPA-priority hormones (testosterone, progesterone, medroxyprogesterone, levonorgestrel, norethindrone, androstenedione, estrone, β-estradiol, α-estradiol, equilin, equilenin, ethinylestradiol, estriol) and BPA. Combinations of ionization source and mobile phases were optimized for improved sensitivity. Suitable chromatographic performances were obtained and the implementation of an on-line SPE washing step consecutive to sample loading was investigated. On-line SPE extraction efficiencies in acceptable ranges (64–79%) and detection limits in the order of nanogram per liter or sub-nanogram per liter were obtained. The linearity range extended over 2–3 orders of magnitude, with determination coefficients (R2) typically > 0.9980. Robust precision and trueness complying with acceptance criteria (70–130%) were obtained for the scope of analytes/matrix combinations. Limited internal standard variations were also observed across samples (±18%), well within the ±50% acceptance criterion. The method was successfully applied to field-collected samples in Canada and summed EDC concentrations were reported in the range of 0.80–2.8 ng L−1, 6.8–19 ng L−1, 260–790 ng L−1, and 37–360 ng L−1 in tap water, surface water, effluent and influent wastewater samples, respectively. [ABSTRACT FROM AUTHOR]

• Polarity switching for simultaneous mass analysis in positive and negative ESI. • Quantitation of organic UV filters in chlorinated waters. • SPE allows for preconcentration of low level analytes in swimming pools. Ultraviolet filters (UVFs) absorb UV light and are comprised of numerous classes of compounds including inorganic and organic. They have been used for decades in protecting humans from skin damage and cancer. Recent studies have shown that UVFs are found in many phases of abiotic and biotic systems with their physical-chemical characteristics determining environmental fate and potential biological impacts such as bioaccumulation. This study developed a unified method to quantify eight UVFs (avobenzone, dioxybenzone, homosalate, octinoxate, octisalate, octocrylene, oxybenzone, and sulisobenzone) by solid phase extraction and ultra-high performance liquid chromatography-tandem mass spectrometry using polarity switching. The validated method resulted in accuracies ranging from 75 to 112%, MLD/MLQs of 0.00015/ 0.00049 to 0.0020/ 0.0067 ng mL−1, and precisions of 1.8 to 22.6% (intraday) and 1.3 to 17.2% (interday). The method was applied to chlorinated outdoor pool waters in the City of Winnipeg, Manitoba, Canada. This method could be adapted for a variety of chlorinated and unchlorinated waters such as drinking water, wastewater, and surface waters. [ABSTRACT FROM AUTHOR]

Abstract: Over the past 20 years, oil sands exploration and processing in Canada have grown steadily, leading to the development of intensive large-scale operations in Alberta, Canada. Naphthenic acids (NAs), a complex mixture of aliphatic and alicyclic carboxylic acids, are by-products of oil sands processing and are known to be toxic. While oil sands processing water (OSPW) is contained in tailings ponds, potential seepage and leaking of OSPW and its contaminants into surrounding surface water systems is a concern. The ability to quantify NAs and their isomers in OSPW surrounding water is essential for monitoring these spills. Unfortunately, quantification of NAs and their isomers is challenging due to the complexity of the NA mixtures, the lack of commercially available standards, and interference from naturally occurring NA compounds. Techniques such as FT-IR and GC/MS are currently used to analyse NAs, but are limited by poor sensitivity and specificity in the case of FT-IR and long sample preparation and instrument run time for GC/MS. To tackle these issues, a rapid LC/MS method was developed which can quickly quantify NAs in surface water with much better sensitivity and specificity than current methods. This method uses large volume injection, ESI negative mode and a Poroshell LC column to improve the method limits of detection (LOD) and quantitation (LOQ). The method is robust and has no complicated sample preparation steps. The method detection limit (MDL) is 0.01mg/L (10ppb) and low limit of quantitation (LLOQ) of 0.1mg/L (100ppb), both for surface water. The developed method was tested with samples from the oil sands producing region, and demonstrated its applicability for fast screening of surface water samples before resorting to costly high accuracy and high resolution mass spectrometry determination. This is the first very rapid LC/MS method using large volume single column direct injection for quantitative determination of naphthenic acids in surface water. [Copyright &y& Elsevier]

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]