Cécile Cren-Olivé

Development of a multi-residue method using acetonitrile-based extraction followed by liquid chromatography-tandem mass spectrometry for the analysis of steroids and veterinary and human drugs at trace levels in soil

The aim of this study was to develop an analytical method for the analysis of traces of hormonal steroids and veterinary and human drugs in soil. Thus, 31 substances were selected, including 14 veterinary products, 11 hormonal steroids and 6 other well-known human contaminant compounds. The procedure inspired by the quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction method was developed. First the acetonitrile-based extraction was optimized. This step was followed by a solid-phase extraction (SPE) clean-up using both a strong anion-exchange cartridge and a polymeric cartridge. The analysis was then performed using liquid chromatography coupled to a triple quadrupole analyser operated with tandem mass spectrometry. This analytical procedure was validated using the ICH/2005 standard by evaluating the linearity (from 0.01 ng/g to 1000 ng/g--R²>0.99), the intra-day precision (relative standard deviation (RSD)<20%), the inter-day precision (RSD<30%), recoveries (40-110% for most of the compounds) and limits of detection and quantification. This method allowed for the determination of the target analytes in the lower ng/g concentration range. The methodology was then applied to real soil samples collected in several areas of France that received different manure or sludge treatments. Some target compounds were detected at very low level (inferior to the ng/g). Veterinary antibiotics, mainly from the sulfonamide family, were found in soils treated by manure (0.02-0.12 ng/g). On the other hand, pharmaceuticals usually used by humans (carbamazepine, ibuprofen) were detected in soils treated by domestic sludge.

Micropollutants in urban stormwater: occurrence, concentrations, and atmospheric contributions for a wide range of contaminants in three French catchments

This study aimed at: (a) providing information on the occurrence and concentration ranges in urban stormwater for a wide array of pollutants (n = 77); (b) assessing whether despite the differences between various catchments (land use, climatic conditions, etc.), the trends in terms of contamination level are similar; and (c) analyzing the contribution of total atmospheric fallout (TAF) with respect to sources endogenous to this contamination. The studied contaminants include conventional stormwater contaminants (polycyclic aromatic hydrocarbons (PAHs), Zn, Cu, Pb, etc.), in addition to poorly or undocumented pollutants such as nonylphenol and octylphenol ethoxylates (NPnEO and OPnEO), bisphenol A (BPA), polybrominated diphenyl ethers (PBDEs), a wide variety of pesticides, and various metals of relevance (As, Ti, Sr, V). Sampling and analysis were performed using homogeneous methods on three urban catchments with different land use patterns located in three distinct French towns. For many of these pollutants, the results do not allow highlighting a significant difference in stormwater quality at the scale of the three urban catchments considered. Significant differences were, however, observed for several metals (As, Cr, Cu, Ni, Sr and Zn), PAHs, and PBDEs, though this assessment would need to be confirmed by further experiments. The pollutant distributions between dissolved and particulate phases were found to be similar across the three experimental sites, thus suggesting no site dependence. Lastly, the contributions of TAF to stormwater contamination for micropollutants were quite low. This finding held true not only for PAHs, as previously demonstrated in the literature, but also for a broader range of molecules such as BPA, NPnEO, OPnEO, and PBDEs, whose high local production is correlated with the leaching of urban surfaces, buildings, and vehicles.

Determination of uptake kinetics and sampling rates for 56 organic micropollutants using "pharmaceutical" POCIS.

The literature increasingly reports sampling rates (Rs) for Polar Organic Chemical Integrative Samplers (POCIS) but the data obtained come from various calibration systems that are not always well-defined (agitation, temperature, measured micropollutant concentrations in water,…). In order to obtain accurate laboratory Rs for priority and emerging substances, POCIS need to be exposed in a robust and well-defined calibration system. Thus, we built a flow-through calibration system containing tap water spiked with 56 organic micropollutants (alkylphenols and phenols, hormones, pesticides, pharmaceuticals, UV filter). POCIS were immersed for up to 28 days. Tap water micropollutant concentrations and additional parameters (temperature, pH, conductivity, dissolved organic carbon, flow velocities) were kept constant and controlled throughout the calibration experiment. Based on the observed uptake kinetics, we distinguished four types of micropollutant accumulation patterns: curvilinear accumulation (30 molecules, group 1), accumulation with an inflexion point (13 molecules, group 2), random accumulation (eight molecules, group 3), and no or very low accumulation (five molecules, group 4). Rs was calculated for 43 out of 56 micropollutants (groups 1 and 2). Calculated Rs values ranged from 0.030 L/d to 0.398 L/d. POCIS can supply TWA concentrations for hormones, pesticides, several pharmaceuticals, a few alkylphenols, and the UV filter. Our Rs results are generally less than two fold-different (higher or lower depending on target molecule) to the literature data using the same type of calibration system or for micropollutants with log Kow>2.65. We found a quadratic correlation between Rs and log D for betablockers, herbicides and hormones.

Determination of the uptake and release rates of multifamilies of endocrine disruptor compounds on the polar C18 Chemcatcher. Three potential performance reference compounds to monitor polar pollutants in surface water by integrative sampling

The uptake kinetics of 27 emerging pollutants on the polar C18 Chemcatcher have been investigated. This investigation determined the sampling rates of 20 compounds, including 16 endocrine disruptors and 4 pharmaceuticals, which were used as overall pollution indicators. Calibrations were completed in a 50-L flow-through microcosm with continuous renewal of tap water spiked with approximately 3 μg/L of each pollutant and with sampling times at 1, 3, 6 and 12h and 1, 3, 7, 14, 21 and 28 days. Exponential regressions for the accumulation kinetics were plotted to confirm the maximum linear uptake times for each molecule using the half time of equilibrium (t(1/2)) criteria. Of the compounds tested, 17 were accumulated linearly for up to 14 or 21 days with an R(2) above 0.98 for linear correlations. The evaluation of the release kinetics of a C18 Chemcatcher spiked with 20 deuterated compounds identified 3 potential performance reference compounds (PRCs) with exponential desorption rates showing relatively good isotropic exchange.

Statistical evaluation of the influence of soil properties on recoveries and matrix effects during the analysis of pharmaceutical compounds and steroids by quick, easy, cheap, effective, rugged and safe extraction followed by liquid chromatography-tandem mass spectrometry

Numerous chemical products are dispersed in our environment. Many of them are recognized as harmful to humans and the ecosystem. Among these harmful substances are antibiotics and steroid hormones. Currently, very few data are available on the presence and fate of these substances in the environment, in particular for solid matrices, mainly due to a lack of analytical methodologies. Indeed, soil is a very complex matrix, and the nature and composition of the soil has a significant impact on the extraction efficiency and the sensitivity of the method. For this reason a statistical approach was performed to study the influence of soil parameters (clay, silt, sand and organic carbon percentages and cation exchange capacity (CEC)) on recoveries and matrix effects of various pharmaceuticals and steroids. Thus, an analysis of covariance (ANCOVA) was performed when several substances were analyzed simultaneously, whereas a Pearson correlation was used to study the compounds individually. To the best of our knowledge, this study is the first time such an experiment was performed. The results showed that clay and organic carbon percentages as well as the CEC have an impact on the recoveries of most of the target substances, the variables being anti-correlated. This result suggests that the compounds are trapped in soils with high levels of clay and organic carbon and a high CEC. For the matrix effects, it was shown that the organic carbon content has a significant effect on steroid hormones and penicillin G matrix effects (positive correlation). Finally, interaction effects (first order) were evaluated. This latter point corresponds to the crossed effects that occur between explanatory variables (soil parameters). Indeed, the value taken by an explanatory variable can have an influence on the effect that another explanatory variable has on a dependent variable. For instance, it was shown that some parameters (silt, sand) have an impact on the effect that clay content has on recoveries. Besides, CEC and silt affect the influence that organic carbon percentage has on matrix effect. This original approach provides a better understanding of the complex interactions that occur in soil and could be useful to understand and predict the performance of an analytical method.

MicroQuEChERS–nanoliquid chromatography–nanospray–tandem mass spectrometry for the detection and quantification of trace pharmaceuticals in benthic invertebrates

Due to industrialization and the use of chemical products in everyday life, various types of drugs and pesticides are present in our environment, which threaten and cause negative impacts on aquatic ecosystems. The consequences of these pollutants are gradually becoming visible. Recent evidence confirms that long term exposure to environmental pharmaceutical concentrations can induce adverse effects in aquatic vertebrates and invertebrates such as reproductive impairments and collapse wild populations. Consequently, one of the challenges of environmental science is to evaluate the associated risks. In this context, a new methodology has been developed using nano-LC-nano-ESI MS/MS to quantify traces of two pharmaceuticals (a neuropharmaceutical drug, fluoxetine, and an anticonvulsant drug, carbamazepine) in two molluscs, Potamopyrgus antipodarum and Valvata piscinalis, which are both prosobranch gastropods. A simple and quick extraction method was developed based on a modified and miniaturized version of the QuEChERS method. The procedure involves the extraction of approximately 10 mg of wet mollusc tissue by 500 µL of a mixture of acetonitrile/water/hexane (50/20/30) and 100 mg of buffer salt. Thus, the extraction step was carried out on an individual scale. The sensitivity of this method allowed for the detection of levels as low as 18 ng/g and 128 ng/g for carbamazepine and fluoxetine, respectively, with recoveries of greater than 85% for the two targeted compounds. This method was then applied to both gastropod species exposed to fluoxetine under laboratory conditions. The results provide evidence of bioaccumulation in both P. antipodarum and V. piscinalis and reveal the inter-species differences.

Multiresidue fully automated online SPE-HPLC-MS/MS method for the quantification of endocrine-disrupting and pharmaceutical compounds at trace level in surface water

The present work describes the development and validation of a sensitive method for the determination of traces of diverse groups of pharmaceuticals and endocrine disruptors in surface water. Thirty-seven substances have been selected, including 10 pesticides, 6 hormonal steroids and assimilates, 12 pharmaceuticals, 5 alkylphenols, 1 chlorophenol and 3 other well-known human contaminants, 1 UV filter and 2 plasticisers. An automated online solid-phase extraction (SPE) is directly coupled to liquid chromatography–tandem mass spectrometry. Different SPE columns have been tested, and the injection volume has been optimised. The developed analytical methodology is based on the direct injection of 2.5 mL of water sample acidified at pH 1.6 on an Oasis HLB loading column (20 × 2.1 mm) with 5-µm particles. Then, the chromatographic separation is achieved on a Kinetex XB C18 (100 × 2.1 mm; 1.7 µm) column, and the quantification is realised in multiple-reaction monitoring mode. The online SPE step warrants minimal sample handling, low solvent consumption, high sample throughput, saving time and costs. This method allows the quantification of the target analytes in the lower ng/L concentration range, with limits of quantification (LQs) between 100 pg/L and 10 ng/L, 26 compounds having LQ lower than 1 ng/L. The monitoring of two selected MS/MS transitions for each compound allows the reliable confirmation of positive findings even at the LQ level. The developed and validated methodology has been applied to the analysis of various real samples from two French rivers. Twelve target compounds have been detected in the environmental samples, and the major pollutants are pharmaceuticals usually used by humans (paracetamol, carbamazepine, oxazepam, ketoprofen, trimethoprim). The pesticides atrazine and carbendazim have been ubiquitously detected in real samples too. Metronidazole, sulfamethoxazole and diuron were also frequently quantified in the water samples.

Determination of endocrine disruptors and endogenic androgens and estrogens in rat serum by high-performance liquid chromatography-tandem mass spectrometry.

To simultaneously measure some targeted endocrine disruptors and several forms of sex hormones in rat serum, an accurate analytical procedure was developed. First, a comparison between a polymeric-based solid-phase extraction (SPE) and a micro-extraction by packed sorbent was performed to choose the optimal method to extract and concentrate the analytes: bisphenol A, atrazine, vinclozolin metabolite, testosterone, androstenedione, estrone, estradiol, estrone-sulfate and glucuronide and estradiol-sulfate and glucuronide. The analyses were then performed by high-performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with electrospray ionisation in positive and negative modes. The protocol based on SPE was validated using the ICH/2005 guidelines. The validation demonstrated good performance in terms of linearity (R(2)>0.99), recovery (71-90%) and repeatability (relative standard deviation: 1-18%). The method was sensitive with LOQ comprised between 0.1 and 0.4 ng/ml for androgens and between 0.098 and 10.2 ng/ml for estrogens. The results obtained on the serum of rats exposed to the targeted endocrine disruptors showed the suitability of this analytical strategy.

Human exposure assessment to a large set of polymer additives through the analysis of urine by solid phase extraction followed by ultra high performance liquid chromatography coupled to tandem mass spectrometry

Polymer items are extensively present in the human environment. Humans may be consequently exposed to some compounds, such as additives, incorporated in these items. The objective of this work is to assess the human exposure to the main additives such as those authorized in the packaging for pharmaceutical products. The urinary matrix was selected to optimally answer this challenge because it has already been proven that the exposure to chemicals can be revealed by the analysis of this biological matrix. A multi-residue analytical method for the trace analysis at ng/mL in human urine was developed, and consisted of an extraction of analytes from urine by solid phase extraction (SPE) and an analysis by ultra-high performance liquid chromatography coupled to a tandem mass spectrometer (UHPLC-MS/MS). Even if the quantification of these compounds was an analytical challenge because of (i) the presence of these substances in the analytical process, (ii) the diversity of their physicochemical properties, and (iii) the complexity of the matrix, the optimized method exhibited quantification limits lower than 25ng/mL and recoveries between 51% and 120% for all compounds. The method was validated and applied to 52 human urines. To the best of our knowledge, this work presents the first study allowing the assessment of the occurrence of more than twenty polymer additives at ng/mL in human urine.

Chemical, microbiological, and spatial characteristics and impacts of contaminants from urban catchments: CABRRES project

Chemical and microbial contaminations of urban waters including stormwater runoff, wastewaters, and combined sewer overflow waters have been shown for a number of years. It is clearly demonstrated, for example, that metallic ions, polycyclic aromatic hydrocarbons (PAH), pesticides, and microbial pathogens can be conveyed by such waters, and they have been found strongly associated with suspended matters. The “Water Framework Directive” (WFD) led to the launching of several research initiatives toward the “Best Management Practices – BMP,” through novel or improved technologies aiming at reducing the ecotoxicological impacts and health risks associated with these waters. Some of these techniques consist at keeping these waters for a certain amount of time in a confined system in order to favor settling of their suspended particles and lead, in part, to the natural biological degradation of their contaminants. These systems are typically impervious basins that can receive stormwaters, e.g. detention basins, biofilters, artificial wetlands, or combined sewer overflows, e.g. stabilization ponds of wastewater treatment lagoons. Several key mechanisms occur in these systems (Fig. 1). The deposits formed constitute areas of high levels of contamination. These structures (basins) are ecosystems with an important biological diversity. They can represent a high risk of contamination of the connected surfaces, streams, or groundwater environments into which they are discharged. Investigations regarding their efficiency at retaining and transforming pollutants and killing undesirable microbes are thus required. When landscaped, these structures may lead to the development of urban public spaces. In this context, they are subjected to social practices generally associated with public gardens, practices which accidentally or regularly expose the public to their contaminants. In addition, these structures require maintenance and specific management, exposing workers to their contaminants. It is therefore essential that the chemical and microbiological contaminants present in these systems are accurately characterized and measured (i.e. which chemical forms and microbial species and genotypes, and how much?), and their health hazards and risks be inferred or estimated. In this context, several biofilters, detention basins, and stabilization ponds have been monitored and investigated around the world. The CABRRES project (Chemical, microbiological, spatial characteristics and impacts of contaminants from urban stormwater detention basins: Assessment and Management of Environmental and Human Health Risks, http://www.graie. org/cabrres), funded by the French National Research Agency (ANR), is one of these research initiatives. It is an interdisciplinary research project (Fig. 2) aiming at better defining the interactions between chemical pollutants (including toxic Responsible editor: Philippe Garrigues