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• A high-risk screening study was performed for patients with chronic kidney disease. • Globotriaosylceramide (Gb 3) was analyzed in dried urine spots by LC-MS/MS. • A total of 397 participants were recruited in four centers across Canada. • No Fabry patients were detected in this study. • Chronic kidney disease might be associated with increased urinary Gb 3 concentrations. Fabry disease is an X-linked lysosomal storage disorder with a highly heterogeneous clinical presentation. This complex disease is caused by a deficient activity of the enzyme α-galactosidase A, which is involved in the catabolism of glycosphingolipids. The prevalence of Fabry disease is underestimated, due to the presence of atypical variants. High-risk screening protocols are particularly relevant for this disease due to the availability of treatments, such as enzyme replacement and chaperone therapies. As kidney manifestations are present in the majority of male and many female patients with Fabry disease, a high-risk screening protocol was performed for patients with chronic kidney disease of unknown etiology. Recruitment of 397 participants took place in four centers across Canada from 2011 to 2017. Globotriaosylceramide (Gb 3) was analyzed in dried urine spots by liquid chromatography/tandem mass spectrometry followed by globotriaosylsphingosine (lyso-Gb 3) on the repeat analysis. The collection and shipment of urine specimens on filter paper resulted in easier handling/shipment and significant cost-saving. No Fabry patients were detected in this study. Increased concentrations of urinary Gb 3 were observed in 13.6% of patients with chronic kidney disease suggesting that chronic kidney disease or other comorbidities might be associated with increased urinary Gb 3 concentrations. [ABSTRACT FROM AUTHOR]

The objectives of this study were to investigate the Fusarium damage-deoxynivalenol (FUS DMG-DON) relationship in various wheat growing locations in western Canada in 2016 and to compare the relationships to the Prairie-wide FUS DMG-DON assessment of that harvest year. Fusarium head blight was prevalent in spring wheat and durum grown in western Canada in 2016. Harvest survey samples for Canada Western Red Spring (CWRS) wheat and Canada Western Amber Durum (CWAD) were inspected for Fusarium damaged kernels, and analyzed using an enzyme-linked immunosorbent assay for the Fusarium-produced mycotoxin DON. For CWAD and most CWRS, there was a significant relationship between FUS DMG (represented as the mass percentage of Fusarium damaged kernels) and DON, whose presence is regulated in food products to minimize consumers' exposure. However, CWRS from south-central Alberta contained much lower DON than expected by the reported visual symptoms of FUS DMG of the samples. High throughput real-time PCR analysis showed that DON-producing Fusarium species were associated with less than 40% of the Fusarium damaged kernels in the CWRS. This was different from what was observed with CWAD grown in the same area in 2016. Multi-mycotoxin analysis by liquid chromatography with tandem mass spectrometry did not show an increased presence of mycotoxins produced by other Fusarium species, and therefore suggested that the observed damage in CWRS from south-central Alberta was not caused by Fusarium species. [ABSTRACT FROM AUTHOR]

Perchlorate is a low molecular weight highly soluble anion. It occurs naturally in the environment, primarily near potash deposits and in arid regions. The determination of perchlorate in human milk is of interest in vulnerable populations such as infants and pregnant women. In this study, a sensitive and selective isotope dilution ion chromatography/tandem mass spectrometry (ID IC-MS/MS) method was developed and validated for the determination of perchlorate in human milk samples collected from the Maternal-Infant Research on Environmental Chemicals (MIREC) Study. The limit of detection (LOD) was 0.27 µg·kg−1 for human milk. A total of 439 human milk samples were analysed with measurable levels of perchlorate in most of the milk samples, and the mean value was 7.62 ± 32.7 µg·kg−1. This project provided important information related to perchlorate levels in human milk collected across Canada and the extent to which pregnant women and their infants may be exposed to perchlorate. A dietary exposure assessment was also conducted in infants based on the measured values in human milk. The mean perchlorate probable daily intakes (PDIs) for infants consuming human milk were 0.31 ± 0.07 μg/kg bw/day for infants under 1 year and 0.17 ± 0.10 μg/kg bw/day for infants between 1 and 3 years old. None of the estimates exceeded the FAO/WHO provisional maximum tolerable daily intake (PMTDI) of 10 μg/kg bw/day. [ABSTRACT FROM AUTHOR]

Human exposure to pesticides commands the implementation of food safety control, but few studies have provided a comparative assessment of conventional and organic products. This study set out to examine 22 pesticides in four distinct commodities (lettuce, apples, grapes, and tomatoes) from conventional and organic agriculture available to consumers. A multiresidue procedure based on QuEChERS extraction and ultra-high-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was first validated for its robustness. Suitable determination coefficients (R2 > 0.99) and recoveries generally between 70 and 110% were obtained. Intraday and interday variations were <20% and low matrix effects were noted with sample-to-sample variation. Method limits of detection (LOD) in the overall range of 0.05–2 μg kg−1 were obtained. The validated method was applied to 133 fruit and vegetable samples purchased in Canada, including conventional and organic culture samples. Overall, 47% of the 133 samples had levels above the LOD for at least one pesticide. Neonicotinoid insecticides were detected in all four product types. Imidacloprid (0.08–29 μg kg−1), acetamiprid (0.11–108 μg kg−1), and clothianidin (0.13–141 μg kg−1) were the most recurrent. Atrazine was reported in approximately a third of the lettuce samples (0.25–7.5 μg kg−1). For varieties with samples available from both organic and conventional agriculture, the proportion of insecticide levels > LOD was significantly higher (p < 0.05) for samples from conventional agriculture (9.7%) than from organic agriculture (2.0%). Measured levels were compliant to Canadian Maximum Residue Limits (MRLs), but a thorough human health risk assessment has yet to be conducted for many of these pesticides. • Multiclass pesticides were analyzed by QuEChERS–LC-MS/MS in fruits and vegetables. • Testing of 133 real samples indicated 47% of positives to at least one pesticide. • Multiple pesticide residues were detected in about half of these positive samples. • Recurrent pesticides were imidacloprid, acetamiprid, clothianidin, and atrazine. • Higher pesticide occurrence was noted in varieties of conventional vs. organic culture. [ABSTRACT FROM AUTHOR]

Nunavimmiut (Inuit of Nunavik, Northern Quebec, Canada) exhibit a high selenium (Se) status because of their frequent consumption of marine mammal foods. Indirect evidence from our previous studies had suggested that selenoneine – a novel selenocompound – may be accumulating in the blood of Nunavimmiut. We used a liquid-chromatography/inductively coupled tandem mass spectrometry (LC-ICP-MS/MS) method to measure concentrations of selenoneine and its methylated metabolite Se-methylselenoneine in archived red blood cells (RBC) obtained from 210 Nunavimmiut living in communities along the Hudson Strait, where marine mammal hunting and consumption are most frequent in Nunavik. This method was adapted to quantify selenoneine and its methylated metabolite in beluga mattaaq, an Inuit delicacy consisting of the skin with the underlying layer of fat and the major dietary source of Se for Nunavimmiut. Total selenium concentration was also measured in RBC and beluga mattaaq samples by isotope dilution ICP-MS/MS. The median selenoneine concentration in RBC was 413 μg Se/L (range = 3.20–3230 μg Se/L), representing 54% (median) of total Se content (range = 1.6–91%). Quantification of selenoneine in five beluga mattaaq samples (skin layer) from Nunavik revealed a median concentration of 1.8 μg Se/g wet wt (range = 1.2–7.4 μg Se/g), constituting 54% (median) of the total Se content (range = 44–74%). Se-methylselenoneine was also detected in Inuit RBC but not in beluga mattaaq, suggesting that selenoneine undergoes methylation in humans. Selenoneine may protect Nunavimmiut from methylmecury toxicity by increasing its demethylation in RBC and in turn decreasing its distribution to target organs. Image 1 • LC-ICP-MS/MS was used to quantify selenoneine and Se-methylselenoneine in RBCs. • Selenoneine represented 54% of total Se content in Inuit RBCs. • Selenoneine was also the major Se species in beluga mattaaq – an Inuit delicacy. • Selenoneine may protect Inuit against methylmercury toxicity. [ABSTRACT FROM AUTHOR]

Failure to attain and sustain long term glycemic control is an ongoing challenge in diabetes therapy. The trend to use a combined therapy and the risk of drug-drug interaction (DDI) are elevated and thus the need for sensitive analytical methods is of great significance. Herein, a simple, robust, and sensitive reverse phase high performance liquid chromatography–electrospray ionization-tandem mass spectrometry (ESI-MS/MS) method for simultaneous determination of metformin (MET) and pioglitazone (PGT) in rat plasma using canagliflozin (CAN) as internal standards (IS) was developed and fully validated. Prior Chromatographic separation on an Agilent Eclipse Plus C18 (4.6 × 100 mm, 3.5 μm) using gradient mobile phase system consisting of ammonium formate pH 4.5 and acetonitrile at a flow rate of 0.5 mL min−1, within a run time of 14 min, the antidiabetic drugs were extracted from rat plasma using acetonitrile-induced protein precipitation technique. Multiple reaction monitoring in positive ion mode was used for quantitation of precursor to production at m / z 130.1 → 71.0 & 60 for MET, 357.2 → 134.2 for PGT, and 462.16 → 191.1 for CAN. Method linearity was obeyed in the range of 1 to 5000 and 1 to 2500 ng mL−1 for MET and PGT, respectively. The developed method was validated in terms of accuracy, precision, selectivity, recovery, matrix effects, and stability as per US-FDA bioanalytical guidelines and successfully applied to clinical pharmacokinetic and DDI studies with a single oral administration of target compounds. The peak plasma concentrations (C max) and area under the concentration-time curve (AUC) of MET was significantly influenced by the concomitant administration of PGT at equal concentration and vice versa. PGT affected the absorption and elimination rate of MET via inhibition of organic cationic transporter (OCT). Molecular modeling study revealed the significant interaction of PGT with OCT. A potential DDI in type 2 diabetic patient receiving chronic treatment with MET and PGT deserves further attention and study to improve drug therapy and prevent adverse effects. • An HPLC-MS/MS assay for simultaneous determination of metformin and pioglitazone in rat plasma • The method fully validated and applied for pharmacokinetic and drug-drug interaction studies. • Pioglitazone affects C max and AUC of MET when co-administered orally. • The study shows for the first time the drug interaction of pioglitazone and metformin. [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]

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]

The increasing variability of the illicit drug market has imposed serious health risks for people who use drugs (PWUD), particularly due to the increasing co-occurrence of opioids and etizolam (or other benzodiazepines) in some jurisdictions. A miniature mass spectrometer (MS) equipped with paper capillary spray ionization was evaluated for its ability to quantify fentanyl, fluorofentanyl, carfentanil, and etizolam in illicit drug samples. Prior to testing actual drug samples, inter- and intra-day reproducibility, calibration linearity, and analytical sensitivity were assessed. The development of a continuous spray solvent delivery system improved MS/MS quantitation by prolonging ionization stability. A simple, rapid and quantitative tandem mass spectrometry method was developed and employed for the analysis of real-world illicit drug samples provided by PWUD at a harm reduction site in Victoria, British Columbia, Canada. Limits of detection ranged from 0.001 to 0.24% w/w of illicit analyte in the original solid drug samples. Target analytes were detected and quantified via the miniature MS system for samples where conventional on-site drug checking technologies were not always effective. These promising results demonstrate the potential role for miniature mass spectrometer systems for on-site drug checking services that can be both sensitive to trace, toxic levels as well as adaptable/selective for new drug threats as they appear in the illicit drug supply. [Display omitted] • The increased variability of the illicit drug market has imposed serious health risks for people who use drugs (PWUD). • A rapid & quantitative miniature MS method was developed and employed for the analysis of real-world illicit drug samples. • Target analytes were quantified via miniature MS, where other on-site drug checking technologies were not always effective. • Miniature MS systems for on-site drug checking services are sensitive, adaptable and selective for new drug threats. [ABSTRACT FROM AUTHOR]

Abstract: Phthalate metabolites are often measured in biomonitoring studies to evaluate a population's exposure to ubiquitous phthalates. During the course of national biomonitoring studies in Canada, we identified an issue with the accuracy of several commercial phthalate metabolite standards that are commonly used in such studies. The validity of the results from these studies was then questioned. Altogether, three (3) large studies were affected, involving a total of 9302 samples and 105000 individual phthalate metabolite measurements. Data from our previous investigation suggested that the inaccuracies in the commercially-available phthalate metabolite standards were compound- and lot-specific. Therefore, an approach was developed to derive correction factors for each lot of phthalate metabolite standard and was applied to the previously-acquired measurements with the goal of obtaining accurate and comparable data. A statistical analysis was performed to support the approach. It is expected that the corrected phthalate metabolite data from all three Canadian biomonitoring studies are comparable to one another. However, caution is still advised when comparing data obtained from biomonitoring studies for which the calibration standards have not been investigated for their accuracy. Suggestions are made based on quality assurance aspects to improve the validity of phthalate metabolite measurements. [Copyright &y& Elsevier]

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]

Analytical methods are generally developed and optimized for specific commodities. Total Diet Studies, representing typical food products 'as consumed', pose an analytical challenge since every food product is different. In order to address this technical challenge, a selective and sensitive analytical method was developed suitable for the quantitation of ochratoxin A (OTA) in Canadian Total Diet Study composites. The method uses an acidified solvent extraction, an immunoaffinity column (IAC) for clean-up, liquid chromatography-tandem mass spectrometry (LC-MS/MS) for identification and quantification, and a uniformly stable isotope-labelled OTA (U-[13C20]-OTA) as an internal recovery standard. Results are corrected for this standard. The method is accurate (101% average recovery) and precise (5.5% relative standard deviation (RSD)) based on 17 duplicate analysis of various food products over 2 years. A total of 140 diet composites were analysed for OTA as part of the Canadian Total Diet Study. Samples were collected at retail level from two Canadian cities, Quebec City and Calgary, in 2008 and 2009, respectively. The results indicate that 73% (102/140) of the samples had detectable levels of OTA, with some of the highest levels of OTA contamination found in the Canadian bread supply. [ABSTRACT FROM AUTHOR]

The multitude of food recalls in 2007 clearly demonstrated that total nitrogen-content (Σ N) determination by means of near-infrared spectroscopy (NIRS) and Kjeldahl-based measurements can be deceived, and should no longer be regarded as a complete quality assurance program for nutritive-protein evaluations. Furthermore, contemporary Canadian-employed analytical tools are precariously limited in their ability to effectively assure a product where there is no a priori knowledge of the environmental toxin(s) involved. In light of these challenges, this study explored a number of analytical techniques used to assess and furthermore assure the quality of vegetable protein products (VPPs). Using liquid chromatography with tandem mass spectrometry (LC/MS/MS) technologies, a combination of VPP-based samples was analyzed for the presence of nitrogen-bearing environmental toxicants. Of the 52 samples tested, involving an assortment of matrices, melamine and cyanuric acid were positively identified (>1 ng/mL) in 22 and 17 samples, respectively. Subsequent high pressure liquid chromatography with ultraviolet/visible (HPLC-UV) amino acid profiling further confirmed the adulteration of those materials contaminated with melamine and melamine-related compounds. Based on the evidence presented herein, LC/MS/MS in combination with HPLC-UV provides for a reliable food safety detection system as applied to VPPs. Moreover, HPLC-UV is indispensable as a stand-alone 1st level of screening to assess the integrity of a VPP or any nutritive protein-based sample. Based on the evidence presented herein, LC/MS/MS in combination with HPLC-UV can provide a reliable food safety monitoring program as applied to VPPs. HPLC-UV is indispensable as a stand-alone 1st level of screening to assess the integrity of a VPP or any nutritive protein-based sample. Future research and development is required to bring the associated instrumentation costs down to a level where they can be adopted on a widespread basis. [ABSTRACT FROM AUTHOR]

Abstract: Several freshwater cyanobacteria species have the capability to produce toxic compounds, frequently referred to as cyanotoxins. The most prevalent of these cyanotoxins is microcystin LR. Recognizing the potential health risk, France, Italy, Poland, Australia, Canada, and Brazil have set either standards or guidelines for the amount of microcystin LR permissible in drinking water based on the World Health Organization guideline of one μg/L of microcystin LR. Recently, the United States Environmental Protection Agency has begun to evaluate the occurrence and health effects of cyanotoxins and their susceptibility to water treatment under the Safe Drinking Water Act through the Contaminant Candidate List (CCL). A recent update of the Contaminant Candidate List focuses research and data collection on the cyanotoxins microcystin LR, anatoxin-a, and cylindrospermopsin. Liquid Chromatography/Tandem-Mass Spectrometry (LC/MS/MS) is a powerful tool for the analysis of various analytes in a wide variety of matrices because of its sensitivity and selectivity. The use of smaller column media (sub 2μm particles) was investigated to both improve the speed, sensitivity and resolution, and to quantify the CCL cyanotoxins, in a single analysis, using Ultra-Performance Liquid Chromatography (UPLC®) combined with tandem mass spectrometry. Natural waters and spiked samples were analyzed to show proof-of-performance. The presented method was able to clearly resolve each of the cyanotoxins in less than eight minutes with specificity and high spike recoveries. [Copyright &y& Elsevier]

Sulfonylurea herbicides are widely used in crop production on the Canadian prairies and a portion of these herbicides applied to cropland are inevitably lost to surrounding aquatic ecosystems. Little is known regarding the presence of sulfonylurea herbicides in wetlands located amongst cropland. This paper describes a new analytical method for the extraction and the determination of seven sulfonylurea herbicides (thifensulfuron-methyl, tribenuron-methyl, ethametsulfuron-methyl, metsulfuron-methyl, rimsulfuron, nicosulfuron and sulfosulfuron) in wetland sediment. The method provided > 85% analyte recovery from fortified sediment for six of the seven sulfonylurea herbicides with a limit of quantification (LOQ) of 1.0 μ g kg- 1. Tribenuron-methyl had significantly lower recovery compared to the other six sulfonylurea herbicides (LOQ = 2 μ g kg- 1). Mean recovery standard deviations were < 10%. This methodology was used to quantify sulfonylurea herbicide residues in sediment samples collected from prairie wetlands situated within the agricultural landscape of Saskatchewan and Manitoba, Canada. This is the first-known detection of sulfonylurea herbicide residues in prairie wetland sediments. Ethametsulfuron-methyl, sulfosulfuron and metsulfuron-methyl, the three most environmentally persistent of the seven sulfonylurea herbicides monitored in the surveillance component of this study, were most frequently detected in wetland sediment with mean concentrations ranging from 1.2 to 10 μ g kg- 1. [ABSTRACT FROM AUTHOR]

Abstract: In recent times, there has been an increased concern over the appearance of human estrogens in marine ecosystem and their effects on the marine habitat. Discharge of raw sewage has been identified as one of the most important sources of human estrogens in the marine environment. Therefore, we have developed a gas chromatography–(ion-trap) mass spectrometry/mass spectrometry method for the analysis of natural estrogens estrone (E1), and 17β-estradiol (E2) and synthetic estrogens 17α-ethynylestradiol (EE2) and diethylstilbestrol (DES) in sewage effluents, seawater and mussels. Recovery of target analytes from mussels (n =3) was above 60% with RSD ranging from 8% to 13%. For aqueous samples (n =3) recoveries were above 80% with RSD ranging from 3% to 7%. Method detection limits for the target analytes ranged from 0.1ngg−1 to 1.0ng/g for mussel sample analysis and from 0.5ngL−1 to 1.2ngL−1 for water sample analysis. The usefulness of the method was demonstrated by analyzing environmental samples from St. John’s and Halifax, Canada, where raw sewage is directly discharged into the harbors. Estrone and 17 β-estradiol were found at 1.5ngL−1 and 1.8ngL−1 in seawater samples collected from St. John’s harbor, while trace amounts of estrone was measured in some mussels collected from Halifax harbor. [Copyright &y& Elsevier]

Non-targeted screening (NTS) in mass spectrometry (MS) helps alleviate the shortcoming of targeted analysis such as missing the presence of concerning compounds that are not monitored and its lack of retrospective analysis to subsequently look for new contaminants. Most NTS workflows include high resolution tandem mass spectrometry (HRMS2) and structure annotation with libraries which are still limited. However, in silico combinatorial fragmentation tools that simulate MS2 spectra are available to help close the gap of missing compounds in empirical libraries. Three NTS tools were combined and used to detect and identify unknown contaminants at ultra-trace levels in surface waters in real samples in this qualitative study. Two of them were based on combinatorial fragmentation databases, MetFrag and the Similar Partition Searching algorithm (SPS), and the third, the Global Natural Products Social Networking (GNPS), was an ensemble of empirical databases. The three NTS tools were applied to the analysis of real samples from a local river. A total of 253 contaminants were identified by combining all three tools: 209 were assigned a probable structure and 44 were confirmed using reference standards. The two major classes of contaminants observed were pharmaceuticals and consumer product additives. Among the confirmed compounds, octylphenol ethoxylates, denatonium, irbesartan and telmisartan are reported for the first time in surface waters in Canada. The workflow presented in this work uses three highly complementary NTS tools and it is a powerful approach to help identify and strategically select contaminants and their transformation products for subsequent targeted analysis and uncover new trends in surface water contamination. [Display omitted] • Hybrid NTS method based on combinatorial and empirical fragmentation databases. • 209 compounds were identified as probable structures and 44 as confirmed structures. • More than 100 compounds were pharmaceuticals and illicit drugs. • Octylphenol ethoxylates, denatonium and telmisartan were confirmed for the first time in surface waters in Canada. [ABSTRACT FROM AUTHOR]

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]

Soxhlet (SE), microwave-assisted (MAE) and ultrasound-assisted (UAE) extraction were compared using ten extraction solvents for their efficiency to extract phenolic and flavonoid antioxidants from Eastern Canada propolis. Extracts were compared for total phenolic (TPC) and total flavonoid (TFC) content, and radical scavenging activities. Anti-inflammatory activity through inhibition of 5-lipoxygenase (5-LO) products biosynthesis in HEK293 cells was also evaluated. The results showed that SE extracts using polar solvents had the highest TPC and TFC. Extracts obtained with ethanol, methanol and acetone were effective free radical scavengers, and showed 5-LO inhibition similar to zileuton. UAE was an effective extraction method since the extracts obtained were comparable to those using SE and the MAE while being done at room temperature. With UAE, extracts of less polar solvents showed similar free radical scavenging and 5-LO inhibition to extracts of much more polar solvents such as methanol or ethanol. Reversed-phase liquid chromatography tandem mass spectrometry confirmed the presence of 21 natural compounds in the propolis extracts based on the comparison of intact mass, chromatographic retention time and fragmentation patterns derived from commercial analytical standards. The current study is the first of its kind to concurrently investigate solvent polarity as well as extraction techniques of propolis. [ABSTRACT FROM AUTHOR]