Simultaneous determination of a variety of endocrine disrupting compounds in carrot, lettuce and amended soil by means of focused ultrasonic solid-liquid extraction and dispersive solid-phase extraction as simplified clean-up strategy

Implementation of simple and effective fine droplet formation-based spray-assisted liquid phase microextraction for the simultaneous determination of twenty-nine endocrine disruptor compounds and pesticides in rock, soil, water, moss, and feces samples from antarctica using gas chromatography-mass spectrometry

This study established the simultaneous determination of the selected endocrine-disrupting compounds (EDCs) and pesticides in rock, soil, water, moss, and feces samples collected from the Antarctic region. The spray-assisted droplet formation-based liquid phase microextraction (SADF-LPME) coupled to GC-MS system was developed and validated for the screening and monitoring of 29 selected EDCs and pesticides. Binary solvent system, 1:1 (v/v) dichlormethane: 1,2-dichloroethane mixture was employed as an extraction solvent and sprayed onto sample or standard solutions using a straightforward and practical spray apparatus. The factors affecting the extraction process such as extraction solvent type and ratio, extraction solvent volume (spray repetition), vortexing period, and sample pH were properly optimized. Analytical figures of the merit of the method were recorded under the optimal extraction/chromatographic conditions. The LOD, LOQ, and enhancement factor were in the range of 1.0 to 6.6 ng/g, 3.2 to 22.1 ng/g, and 3.7 to 158.9, respectively. The method demonstrated a good linear working range for all the selected analytes with proper coefficients of determination. The usability and reliability of the microextraction strategy was confirmed using seawater, moss, and soil samples, and the %recoveries were within an acceptable range (> 70%) for all examined samples. The environmental samples collected from the Horseshoe and Faure Islands of the Antarctica region were analyzed to assess the potential pollution of EDCs and pesticides. This method has the potential to be employed for the analysis of EDCs in routine analytical laboratories and for controlling and screening the organic pollutant content of different environmental samples.

Effect-directed analysis of a hospital effluent sample using A-YES for the identification of endocrine disrupting compounds

An effect-directed analysis (EDA) approach was used to identify the compounds responsible for endocrine disruption in a hospital effluent (Basque Country). In order to facilitate the identification of the potentially toxic substances, a sample was collected using an automated onsite large volume solid phase extraction (LV-SPE) system. Then, it was fractionated with a two-step orthogonal chromatographic separation and tested for estrogenic effects with a recombinant yeast (A-YES) in-vitro bioassay. The fractionation method was optimized and validated for 184 compounds, and its application to the hospital effluent sample allowed reducing the number of unknowns from 292 in the raw sample to 35 after suspect analysis of the bioactive fractions. Among those, 7 of them were confirmed with chemical standards. In addition, target analysis of the raw sample confirmed the presence of mestranol, estrone and dodemorph in the fractions showing estrogenic activity. Predictive estrogenic activity modelling using quantitative structure-activity relationships indicated that the hormones mestranol (5840 ng/L) and estrone (128 ng/L), the plasticiser bisphenol A (9219 ng/L) and the preservative butylparaben (1224 ng/L) were the main contributors of the potential toxicity. Derived bioanalytical equivalents (BEQs) pointed mestranol and estrone as the main contributors (56 % and 43 %, respectively) of the 50 % of the sample's explained total estrogenic activity.

Targeted screening of 11 bisphenols and 7 plasticizers in food composites from Canada and South Africa

A sensitive method based on ultrasound-assisted liquid extraction coupled with liquid chromatography was applied to screen 18 plastic-related contaminants in 168 food composites (namely fish fillets, chicken breast, canned tuna, leafy vegetables, bread and butter) collected in Montreal (Canada), Pretoria and Vhembe (South Africa). Bisphenol A (BPA), bisphenol S (BPS) and seven plasticizers (di-n-butyl phthalate (DBP), diethyl phthalate (DEP), (2-ethylhexyl) phthalate (DEHP), di-(2-ethylhexyl) adipate (DEHA), di-isononyl phthalate (DINP), di-(isononyl)-cyclohexane-1,2-dicarboxylate (DINCH)) were detected in different foods from both countries. DBP and DEP were the most frequently detected contaminants in food collected in Montreal (75% for both) and DINP was the most frequently detected contaminant in food from South Africa (67%). DEHA concentration in packaged fish were significantly higher than the values for non-packaged fish (p < 0.01) suggesting that the packaging film can be one source of DEHA in fish.

Evaluation of three sorbent-phase extraction techniques based on hyper-crosslinked polymer for the extraction of five endocrine disrupters in water

A series of low-cost hyper-crosslinked polymers were prepared by an easy one-step Friedel-Crafts reaction. The synthesized hyper-crosslinked polymers exhibited remarkably porous structure, large surface area, and hydroxyl groups, which can be employed as an ideal adsorbent material for novel sorbent-phase extraction techniques. Based on this, using hyper-crosslinked polymers as sorbent and coating, three novel extraction methods, including micro-solid-phase extraction, dispersive solid-phase extraction, and solid-phase microextraction, were explored and evaluated for simultaneous measurement of five endocrine-disrupting compounds (triclosan and bisphenol A, tetrabromobisphenol A, tetrabromobisphenol A bisallylether, and tetrabromobisphenol A bis(2,3-dibromopropyl ether)) in environment water prior to high-performance liquid chromatography-ultraviolet. The influence of experimental parameters on three extraction techniques such as extraction time, the amount of hyper-crosslinked polymers, extraction temperature, ionic strength, and desorption conditions were optimized. Three previously mentioned methods provided limits of detection ranging from 0.01 to 0.05 μg/L, and high recoveries (85-99%) with relative standard deviations of 1.7-5.6%. This study presented the merits and disadvantages of three proposed extraction methods and their potential for effective monitoring of hazardous pollutants in real water samples.

Ultrasound-assisted electromembrane extraction with supported semi-liquid membrane

Electromembrane extraction (EME), involving the migration of charged analytes across a supported liquid membrane (SLM) with an external power supply, is a promising sample preparation method in analytical chemistry. However, the presence of boundary double layers at the SLM/solution interfaces often restricts extraction efficiency. To avoid this, the current work proposed an ultrasound-assisted EME (UA-EME) method based on a novel type of supported semi-liquid membrane (SsLM). The characterizations showed that the SsLM was stable under ultrasound conditions. Ultrasound was found to reduce the boundary double layers and thus increase the mass transfer. Major operational parameters in UA-EME including ultrasound power density, temperature, applied voltage and extraction time were optimized with haloperidol, fluoxetine, and sertraline as model analytes. Under the optimal conditions, extraction recoveries of model analytes in water samples were in the range of 66.8%-91.6%. When this UA-EME method was coupled with LC-MS/MS for detection of the target analytes in human urine samples, the linear range of the analytical method was 10-1000 ng mL^-1, with R² > 0.997 for all analytes. The limits of detection (LOD) and limits of quantification (LOQ) were in the range of 1.7-2.1 ng mL^-1 and 5.7-6.7 ng mL^-1, respectively. The UA-EME expands the application field of ultrasound chemistry and will be very important in development of stable and fast sample preparation systems in the future.

Sample Preparation and Analytical Methods for Steroid Hormones in Environmental and Food Samples: An Update Since 2012

Steroid hormones (SHs) have been widely used over the past few decades as both human and veterinary drugs to prevent or treat infectious diseases and anti-inflammatory benefits in clinical. Unfortunately, their residues in foodstuffs and environmental samples can produce adverse effects on human and animal life such as disrupting the endocrine system. For these reasons, sensitive, simple and efficient methods have been developed for the determination of these compounds in various matrices. This critical review summarized the articles published in the period from 2012 to 2019 and can be used to help researchers to understand development of the sample pretreatment protocols and analytical methods used to detect SHs. The developed extraction and purification techniques used for steroids in different samples, such as cloud point extraction, solid phase extraction based on different novel materials, microextraction methods, QuEChERS and other methods are summarized and discussed. Analytical methods used to quantify these compounds, such as different chromatography methods, electrochemical methods, as well as other methods, are illustrated and compared. We focused on the latest advances in SHs pretreatment, and the application of new technologies in SHs analysis.

Phenols in soils and agricultural products irrigated with reclaimed water

The presence of phenols, such as nonylphenol (NP), bisphenol (BPA), and octylphenol (OP), in the environment have been receiving increased attention due to their potential risks to human health and environment. The use of reclaimed water for irrigation may be one of the sources of these phenols in the agricultural system. A field experiment was conducted to assess the effects of reclaimed water irrigation on phenol contamination of agricultural topsoil and products in the North China Plain between 2015 and 2016. Three irrigation treatments were applied to all crops: reclaimed water irrigation, groundwater irrigation and alternative irrigation with reclaimed water and groundwater (1:1, v/v). The results showed that the concentrations of NP, BPA, and OP in the topsoil were 0.02-0.54, 0.004-0.06, and ND-9.9 × 10^-3 mg/kg, respectively; the corresponding values in agricultural products were 0.007-0.70, 0.004-0.24, and ND-1.08 mg/kg, respectively. The concentration of NP in the topsoil and agricultural products and that of BPA in the agricultural products were all less than the recommended limits. The yields of wheat, maize, vegetables were 4.35-7.08, 1.03-6.46, and 10.9-67.0 t/ha, respectively. The bioaccumulation factors (BCFs) of OP, NP, and BPA for cereals were 0.7-4.77, 0.16-4.59, and 1.3-23.9, respectively; the corresponding values in vegetables were 0.0-4.53 (except cucumber and eggplant), 0.38-12.6, and 0.57-24.3, respectively. No significant differences in phenol concentrations, BCFs, or yields of wheat and vegetables were observed among the three irrigation treatments. In conclusion, compared with groundwater irrigation, reclaimed water irrigation in this experiment did not significantly affect phenol concentrations in the topsoil and agricultural products as well as BCFs and yields of wheat and vegetables. However, because the quality of reclaimed water may vary across collected areas, additional experiments are warranted to analyze the effects of reclaimed water irrigation on the risk of phenol contamination.

A multi-residue method for determining twenty-four endocrine disrupting chemicals in vegetables and fruits using ultrasound-assisted solid-liquid extraction and continuous solid-phase extraction

In this work, we developed an analytical approach using an ultrasound-assisted extraction (UAE) followed by continuous solid-phase extraction (SPE) and gas chromatography-mass spectrometry (GC-MS) detection in order to determine simultaneously 24 endocrine disrupting chemicals such as alkylphenols, organophosphorus pesticides, parabens, phenylphenols, triclosan and bisphenol A in vegetable and fruit samples. Different variables influencing UAE and SPE performance were optimized in order to maximize removal of the sample matrix and preconcentration of the analytes. The optimized extraction and GC-MS quantitation conditions provided acceptable sensitivity, selectivity, accuracy and precision. Limits of detection spanned the range 0.6-25 ng kg^-1, recoveries were near-quantitative and relative standard deviations ranged from 4.5 to 7.6%. The proposed method was used to analyse 11 vegetable samples and 7 fruit samples purchased at various Spanish and Moroccan supermarkets. Most samples contained more than three of the analytes, at levels between 5.8 and 580 ng kg^-1.

Miniaturized analytical methods for determination of environmental contaminants of emerging concern - A review

The determination of contaminants of emerging concern (CECs) in environmental samples has become a challenging and critical issue. The present work focuses on miniaturized analytical strategies reported in the literature for the determination of CECs. The first part of the review provides brief overview of CECs whose monitoring in environmental samples is of particular significance, namely personal care products, pharmaceuticals, endocrine disruptors, UV-filters, newly registered pesticides, illicit drugs, disinfection by-products, surfactants, high technology rare earth elements, and engineered nanomaterials. Besides, an overview of downsized sample preparation approaches reported in the literature for the determination of CECs in environmental samples is provided. Particularly, analytical methodologies involving microextraction approaches used for the enrichment of CECs are discussed. Both solid phase- and liquid phase-based microextraction techniques are highlighted devoting special attention to recently reported approaches. Special emphasis is placed on newly developed materials used for extraction purposes in microextraction techniques. In addition, recent contributions involving miniaturized analytical flow techniques for the determination of CECs are discussed. Besides, the strengths, weaknesses, opportunities and threats of point of need and portable devices have been identified and critically compared with chromatographic methods coupled to mass chromatography. Finally, challenging aspects regarding miniaturized analytical methods for determination of CECs are critically discussed.

Does the application of human waste as a fertilization material in agricultural production pose adverse effects on human health attributable to contaminants of emerging concern?

The QuEChERS (quick, easy, cheap, effective, rugged, and safe) ultrasound-assisted method was successfully used to determine the presence of contaminants of emerging concern (CECs) in both the growing medium (i.e. soil) and vegetable samples (i.e. potato, onion, celery, parsnip and carrot) cultivated in household gardens under field conditions impacted by the application of livestock manure mixed with human waste. CECs with a broad range of physico-chemical properties including pharmaceuticals, plasticizers, herbicides, personal care products, and biocides were investigated. Among all studied CECs, diclofenac (DCL), carbamazepine, bisphenol A (BPA) and estrogenic hormones (estrone (E1), 17α-ethinyl estradiol (EE2)) were detected and quantified in vegetable samples with a concentration range from 0.114 to 13.3 ng/g fresh weight (f.w.), while BPA, E1, and EE2 were detected in soil samples with concentration ranges from 0.526 to 0.830 ng/g f.w., 0.121-0.199 ng/g f.w. and 0.118-0.333 ng/g f.w., respectively. DCL was only quantified above the limit of quantification in one soil sample (0.151 ng/g f.w.). The human health risk was estimated using the threshold of toxicological concern approach and a standard diet for two segments of the population (i.e. adult and child). The consumption of investigated vegetables contaminated with CECs poses no risk for the Serbian population.

Humic acid functionalized hyperbranched polytriazine based dispersive solid-phase extraction for acaricides determination in tea matrix

Hyperbranched polytriazine functionalized with humic acid was prepared and developed as new sorbents for dispersive solid-phase extraction of three acaricides (clofentezine, fenpyroximate, and pyridaben) in tea samples combined with high-performance liquid chromatography detection. The sorbents were characterized by scanning electron microscopy, energy dispersive spectroscopy, Zeta-potential, and Fourier transform infrared spectroscopy. The extraction parameters (extraction time, ionic strength, desorption conditions) were optimized. The adsorption mechanism was evaluated utilizing Fourier transform infrared spectra. Under optimum conditions, satisfactory analytical performances were achieved, which included high precision (1.33-9.62%), low limits of detection (0.19-3.54 µg/L), and wide linear range (2.5-500 µg/L) for the analysis of the acaricides. Moreover, the proposed method proved highly effective for the determination of acaricides in tea samples, with the relative recoveries in the range of 65.20-108.13% and relative standard deviations < 9.87%. The method has great application potential for the detection of acaricides in tea samples.

Effects of bisphenol A on post-embryonic development of the cotton pest Spodoptera littoralis

Endocrine-disrupting chemicals encompass a variety of chemicals that may interfere with the endocrine system and produce negative effects on organisms. Among them, bisphenol A is considered a major pollutant in numerous countries. The harmful effects of BPA on environmental and human health are intensely studied. However, the effects of BPA on terrestrial insects are still poorly investigated, despite that several plants can accumulate BPA in their tissues, leading to potential contamination of herbivorous insects. Here, we used the leafworm Spodoptera littoralis, a polyphagous species, to study BPA effects on post-embryonic development. We studied the effects of BPA ingestion at environmental doses (e.g., 0.01, 0.1, and 1 μg/g of BPA) and high doses (e.g., 25 μg/g) on larval weight and stage duration, pupal length and sex ratio. BPA effects were investigated in more detail during the last larval instar, a crucial period for preparing pupation and metamorphosis, which are under endocrine control. We monitored the haemolymph concentration of ecdysteroids, hormones controlling moult and metamorphosis, as well as the expression levels of several nuclear receptors involved in the ecdysteroid signalling pathway. Our integrative study showed that, upon exposure doses, BPA can induce various effects on the viability, developmental time, growth and sex ratio. These effects were correlated with a delay of the ecdysteroid peak during the last larval instar and a modification of expression of EcR, USP, E75AB, E75D and Br-c. We provide new evidence about the events that occur after BPA exposure in insect contaminated by food ingestion.

High through-put determination of 28 veterinary antibiotic residues in swine wastewater by one-step dispersive solid phase extraction sample cleanup coupled with ultra-performance liquid chromatography-tandem mass spectrometry

We developed a QuEChERS (quick, easy, cheap, effective, rugged and safe) method for the high through-put determination of 28 common veterinary antibiotics in swine wastewater using one-step dispersive solid-phase extraction (d-SPE) for sample cleanup and ultra-performance liquid chromatography-tandem mass spectrometry for detection. The orthogonal test method was used to systematically investigate the parameters that might influence d-SPE efficiency. The optimal d-SPE procedure utilized 40 mg primary secondary amine sorbent and 3 g L^-1 Na₂EDTA. The recoveries ranged from 50 to 100% with relative standard deviations <20% for all target analytes except for enrofloxacin and chlortetracycline. The limits of detection and limits of quantification for all the analytes ranged from 0.002 to 0.200 ng mL^-1 and 0.005-0.500 ng mL^-1, respectively. The developed method was successfully applied to the analysis of 28 antibiotic residues in swine wastewater from 10 pig farms located in central China. Fourteen antibiotics including 4 sulfonamides (sulfadiazine, sulfamerazine, sulfamonomethoxine and trimethoprim), 5 fluoroquinolones (norfloxacin, ciprofloxacin, pefloxacin, enrofloxacin, and ofloxacin), 1 lincosamide (lincomycin) and 4 tetracyclines (doxycycline, tetracycline, oxytetracycline, and chlortetracycline) were detected at levels ranging from 0.0560 to 1793 ng mL^-1. Our results demonstrated that the optimized method is a simple but reliable analytical technique for the routine monitoring of veterinary antibiotics in swine wastewater. Swine wastewater samples that we analyzed from 10 pig farms in Jiangxi Province, China were highly contaminated and pose a serious threat to ecosystems and to public health.

An Immunoaffinity Purification Method for the Simultaneous Analysis of Triclocarban and Triclosan in Foodstuffs by Liquid Chromatography Tandem Mass Spectrometry

Triclocarban (TCC) and triclosan (TCS) have been simultaneously detected in five kinds of foodstuffs using an immunoaffinity purification method coupled with ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) for the first time. Two highly specific monoclonal antibodies against TCC and TCS were produced and coupled to N-hydroxysuccinimide-activated Sepharose 6B gel to prepare the immunosorbent. Under the optimal conditions, mean recoveries from spiked samples by the IAC-UHPLC-MS/MS method were 70.1-92.8% for TCC and 76.6-102.5% for TCS. Intraday relative standard deviations were below 14.5%. The limits of quantification (LOQs) of TCC were 1 ng/L for beverage samples and 0.01-0.02 μg/kg for food samples. The LOQs of TCS were 0.03 μg/L for beverage samples and 0.2-0.3 μg/kg for food samples. The applicability of the method has been proven by analyzing TCC and TCS in different samples from supermarkets in Beijing. The proposed method is sufficiently sensitive and reliable for monitoring trace concentrations of TCC and TCS in food samples.

Dispersive liquid-liquid microextraction as a new clean-up procedure for the determination of parabens, perfluorinated compounds, UV filters, biocides, surfactants, and plasticizers in root vegetables

An analytical method based on ultrasound-assisted extraction and dispersive liquid-liquid microextraction (DLLME) clean-up has been developed and validated for the determination of 31 emerging pollutants in root vegetables. The target compounds were four preservatives, six perfluoroalkyl compounds, six UV filters, two biocides, eight anionic surfactants, three nonionic surfactants, and two plasticizers. The type and volume of the extraction solvent, those of the disperser solvent, the pH and NaCl content of the DLLME aqueous phase, the amount of sample, and the sonication time were optimized. Box-Behnken experimental design was applied to select the best extraction conditions. Matrix-matched calibration curves were used for quantification. Four internal standards were used to compensate for residual matrix effects. Good linearity (R² > 0.990), accuracies (expressed as the relative recovery) of >82%, and precisions (expressed as the relative standard deviation) of <18% were achieved. Method quantification limits (MQLs), calculated from spiked samples as the concentrations corresponding to signal-to-noise ratios of 10, were in the range 0.1-25 ng g^-1 dry weight (d.w.). MQL values for 26 of the 31 target compounds were lower than 5 ng g^-1 d.w. The method was successfully applied to determine the target pollutants in carrots, potatoes, and turnips from a local market. To the best of our knowledge, the proposed method constitutes the first application of DLLME as a clean-up procedure for the multiresidue determination of emerging pollutants in vegetables. The method affords similar recoveries and method detection limits to previously reported methods but requires smaller solvent volumes and sample amounts and is less expensive.

Tissue storage affects lipidome profiling in comparison to in vivo microsampling approach

Low-invasive in vivo solid-phase microextraction (SPME) was used to investigate the lipid profiles of muscle tissue of living fish. Briefly, mixed mode SPME fibers were inserted into the muscle for 20 min extraction, and then the fibers were desorbed in an optimal mixture of solvents. The obtained lipid profile was then compared and contrasted to that obtained with employment of ex vivo SPME and solid-liquid extraction (SLE) from fish muscle tissue belonging to the same group of fish, following a one-year storage period. Ex vivo SPME analysis of stored muscle samples revealed 10-fold decrease in the number of detected molecular features in comparison to in vivo study. Moreover, in vivo microsampling enabled the identification of different classes of bioactive lipids, including fatty acyls, not present in the lipid profile obtained through ex vivo SPME and SLE, suggesting the alterations occurring in the unbound lipid fraction of the system under study during the storage and also indicating the advantage of the in vivo extraction approach.

Bisphenol A and alkylphenols concentrations in selected mariculture fish species from Pulau Kukup, Johor, Malaysia

Endocrine disrupting compound (EDC) contamination in food is a global concern. Concerning potential environmental and human health exposed to EDCs via food intake, an experiment was conducted on the selected EDCs concentration in the mariculture fish, Trachinotus blochii (golden pomfret), Lutjanus campechanus (snapper), and Lates calcarifer (sea bass) at Pulau Kukup, Johor. Mariculture activity at Pulau Kukup involves active export of fishes to Singapore and Indonesia. The recovery of BPA (bisphenol A), 4OP (4-octylphenol), and 4NP (4-nonylphenol) were 61.54%-93.00%, 16.79%-17.13%, and 61.24%-71.49%, respectively. Relatively high concentration of BPA was recorded in T. blochii (0.322ng/g), followed by L. calcarifer (0.124ng/g) and L. campechanus (0.023ng/g). Furthermore, 4OP and 4NP were detected only in T. blochii at concentrations of 0.084ng/g and 0.078ng/g, respectively. The results of the present study provide insights on monitoring and managing mariculture activity in relation to environmental protection and food safety.

Multi-class of endocrine disrupting compounds in aquaculture ecosystems and health impacts in exposed biota

Fishes are a major protein food source for humans, with a high economic value in the aquaculture industry. Because endocrine disrupting compounds (EDCs) have been introduced into aquatic ecosystems, the exposure of humans and animals that depend on aquatic foods, especially fishes, should be seriously considered. EDCs are emerging pollutants causing global concern because they can disrupt the endocrine system in aquatic organisms, mammals, and humans. These pollutants have been released into the environment through many sources, e.g., wastewater treatment plants, terrestrial run-off (industrial activities, pharmaceuticals, and household waste), and precipitation. The use of pharmaceuticals, pesticides, and fertilizers for maintaining and increasing fish health and growth also contributes to EDC pollution in the water body. Human and animal exposure to EDCs occurs via ingestion of contaminated matrices, especially aquatic foodstuffs. This paper aims to review human EDC exposure via fish consumption. In respect to the trace concentration of EDCs in fish, types of instrument and clean-up method are of great concerns.

Procedures of determining organic trace compounds in municipal sewage sludge-a review

Sewage sludge is the largest by-product generated during the wastewater treatment process. Since large amounts of sludge are being produced, different ways of disposal have been introduced. One tempting option is to use it as fertilizer in agricultural fields due to its high contents of inorganic nutrients. This, however, can be limited by the amount of trace contaminants in the sewage sludge, containing a variety of microbiological pollutants and pathogens but also inorganic and organic contaminants. The bioavailability and the effects of trace contaminants on the microorganisms of soil are still largely unknown as well as their mixture effects. Therefore, there is a need to analyze the sludge to test its suitability before further use. In this article, a variety of sampling, pretreatment, extraction, and analysis methods have been reviewed. Additionally, different organic trace compounds often found in the sewage sludge and their methods of analysis have been compiled. In addition to traditional Soxhlet extraction, the most common extraction methods of organic contaminants in sludge include ultrasonic extraction (USE), supercritical fluid extraction (SFE), microwave-assisted extraction (MAE), and pressurized liquid extraction (PLE) followed by instrumental analysis based on gas or liquid chromatography and mass spectrometry.

Quantitative mass spectrometry methods for pharmaceutical analysis

Quantitative pharmaceutical analysis is nowadays frequently executed using mass spectrometry. Electrospray ionization coupled to a (hybrid) triple quadrupole mass spectrometer is generally used in combination with solid-phase extraction and liquid chromatography. Furthermore, isotopically labelled standards are often used to correct for ion suppression. The challenges in producing sensitive but reliable quantitative data depend on the instrumentation, sample preparation and hyphenated techniques. In this contribution, different approaches to enhance the ionization efficiencies using modified source geometries and improved ion guidance are provided. Furthermore, possibilities to minimize, assess and correct for matrix interferences caused by co-eluting substances are described. With the focus on pharmaceuticals in the environment and bioanalysis, different separation techniques, trends in liquid chromatography and sample preparation methods to minimize matrix effects and increase sensitivity are discussed. Although highly sensitive methods are generally aimed for to provide automated multi-residue analysis, (less sensitive) miniaturized set-ups have a great potential due to their ability for in-field usage.This article is part of the themed issue 'Quantitative mass spectrometry'.

Application of matrix solid-phase dispersion followed by GC-MS/MS to the analysis of emerging contaminants in vegetables

A multiresidue method for the determination of 17 emerging contaminants in vegetables was developed based on ultrasound-assisted matrix solid-phase dispersion (MSPD). The analysis was performed using isotope dilution gas chromatography tandem mass spectrometry. In the development of the MSPD procedure, different parameters such as sonication and the type of sorbent or extraction solvent were assayed. Manual and in situ derivatization was assayed and the chromatographic response was higher when the reaction takes place in the injection port. The limits of detection obtained for the studied compounds were in the range of 0.1-0.4ngg(-1) for the different vegetables analyzed. The developed method was applied to vegetables obtained from several local markets. At least one of the organophosphates was detected in the analyzed samples at levels ranging from 0.6 to 4.6ngg(-1) and bisphenol A was detected in all the samples at concentration up to 16ngg(-1).

Comprehensive characterization of anticoagulant rodenticides in sludge by liquid chromatography-tandem mass spectrometry

The occurrence of 10 commonly used anticoagulant rodenticides in centrifuged sludge of 27 wastewater treatment plants was evaluated using solid-liquid extraction (SLE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Activated carbon, alumina, and Florisil cartridges with methanol/dichloromethane as eluting solvents were tested in combination with primary-secondary amine (PSA) to optimize an efficient sample cleanup. PSA in combination with Florisil was the best methodology to extract anticoagulant rodenticides in sludge providing recoveries between 42 ± 0.5 and 100 ± 2 %. Warfarin, bromadiolone, ferulenol, and coumachlor were the most ubiquitous compounds in sludge at concentrations up to 84.2 ng g(-1) for the latter. Coumatetralyl, dicoumarol, and brodifacoum were detected sporadically at levels between 6.1 and 17.4 ng g(-1). On the contrary, acenocoumarol, difenacoum, and flocoumafen were not detected in any sample. Finally, we estimated the amount of anticoagulant rodenticides discharged via sludge in order to determine the potential impact to agricultural soil according to different sludge usage practices in the region investigated. This study demonstrates that anticoagulant rodenticides are accumulated in sludge during activated sludge treatment and that the application of sludge as fertilizers may pose a future environmental risk, if not controlled.