Session 28 - Emerging pollutants

The main objectives of this study were to develop rapid and accurate screening multiresidue pesticide methods on the basis of Solid-Phase Extraction (SPE) technique for the determination of 10 pesticides in water samples and on the basis of QuEChERS technique regarding sediments samples. The target compounds were determined by Gas Chromatography-Mass Spectrometry (GC-MS). The method was validated in terms of accuracy, precision, linearity, detection and quantification limits. The recovery percentages obtained for the pesticides in water samples at three different concentration levels, ranged between 73.2 to 101.2%, with relative standard deviations below 9.3%. The corresponding results from the sediment ranged between 69.5 to 122.7% with relative standard deviations below 11.2%. The limits of detection for the pesticides in water and sediment were below 12 ng L-1 and 9 mg kg-1, respectively. The optimized methods were applied in Epirus region (North-Western Greece) to determine the concentration level of the target compounds in sea water and sediment samples. The analytical methodologies exhibited excellent analytical characteristics and proved to be reliable for the estimation of the pollutant load in sea water and sediment samples from marine aquaculture.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:33 to 13:36
Flash presentation in Emerging pollutants

Daily flow-proportional composite influent wastewater was collected from the Wastewater Treatment Plant (WWTP) in Athens during a nine-year sampling campaign (2010-2019). Analytes in influent wastewater are markers of the consumption and the exposure of the chemicals in the population. Wastewater samples were cleaned up and enriched 200 times using a generic solid phase extraction protocol based on a mixture of four sorbent materials capable of retaining a wide-range of analytes. Extracts were analyzed by a wide-scope targeted LC-QTOFMS and by highly-sensitive LC-MS/MS methods for the determination of pharmaceuticals such as antidepressants, anxiolytics, antipsychotics, antibiotics, antiepileptics, analgesics, nonsteroidal anti-inflammatory drugs (NSAIDs), diuretics, antihypertensives, antiulcer, and steroids as well as the main illicit drugs and their metabolites among others. Furthermore, the daily consumption of the substances was back-calculated with the aim of revealing trends in the use patterns of the compounds and associate the changes with socioeconomic phenomena, law enforcements and financial indicators.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:30 to 13:33
Flash presentation in Emerging pollutants

New sustainable technologies are needed to tackle pharmaceuticals contamination in different environmental compartments. Bioremediation technology, using native microorganisms with capacity for partial or complete elimination of contaminants, can be considered. This work investigated the capability of different bacterial strains to biodegrade paroxetine and bezafibrate, either as a bacterial consortium or as a single strain. These strains were isolated from bacterial cultures previously enriched under static conditions with paroxetine or bezafibrate, using as inoculum an estuarine sediment. All strains were identified through 16S rRNA gene sequencing. Degradation potential was accessed by analyzing pharmaceutical compounds in the culture medium and fluoride ion release (only for paroxetine). The genus Pseudomonas, widely reported in biodegradation studies, was predominant among the isolated bacterial strains. Most bacterial strains showed potential to degrade paroxetine (55%-100%) as a single strain in co-metabolism with sodium acetate. Furthermore, bacterial consortia also presented high removal efficiencies (>85%) for paroxetine throughout 4 weeks. For bezafibrate, tests showed a high potential of the bacterial consortia to degrade this compound (>90%).

Session: 28, Room: D, at Fri, 09/06/2019 - 12:30 to 12:45
Oral presentation in Emerging pollutants

A rapid magnetic solid-phase extraction (MSPE) method coupled to Gas Chromatography-Mass Spectrometry (GC-MS) was developed for the simultaneous extraction of ten pesticides belonging to various categories (insecticides, herbicides and fungicides) in environmental water samples. The magnetic Fe3O4@SiO2@C18 nanoparticles were synthesized by coprecipitation of Fe2+ and Fe3+ ions, at alkaline conditions, under hydrothermal treatmentand andused as adsorbents of MSPE.
The proposed method is optimized by means of experimental design and response surface methodology. Several parameters influencing MSPE efficiency were investigated. The most important were the amount of the sorbent and the extraction time. Under optimal conditions, the MSPE-GC-MS method presented fast simple separation and analysis, and excellent linearity in the range of 6.4–5000.0 ng/L, with coefficients of determination (R2) higher than 0.9901 for all compounds. Moreover, the performance of the MSPE method was compared to a conventional SPE and the MSPE method was comperable.
Finally, the optimized method was applied in a case-control study carried out in Rivers Aliakmonas, Loudias and Axios (Macedonia Region-North Greece). The most frequently detected compounds were atrazine, methyl-parathion, chlorpyriphos and irgarol.
The magnetic Fe3O4@SiO2@C18 composites based MSPE method proved promising for convenient and efficient determination of pesticides in environmental water samples.

Session: 28, Room: D, at Fri, 09/06/2019 - 12:45 to 13:00
Oral presentation in Emerging pollutants

Nitrofurans (NFs) are synthetic antibiotic drugs employed for the treatment of bacterial diseases in livestock production or as food additives in industrial farming of food-producing animals. The most widely used NFs in veterinary medicine are nitrofurantoin (NFT), furazolidone (FZD), nitrofurazone (NFZ) and furaltadone (FTD). After intake, NFs are extensively metabolized into their corresponding metabolites (NFMs), identified as 1-amino-hydantoin (AHD), 3-amino-2-oxazolidone (AOZ), semicarbazide (SEM) and 3-amino-5-methyl-morpholino-2-oxazolidinone (AMOZ), for nitrofurantoin, furazolidone, nitrofurazone and furaltadone, respectively. NFs and their metabolites are suspected to possess carcinogenic and mutagenic potency, therefore their application in food and animal production was banned in the EU in 1995 and in the USA in 2002. Since parent NFs are extensively metabolized to tissue-bond metabolites, recent analytical methods have been focused on the determination of the NFMs instead of the parent compounds. In the present study a modified extraction technique including at first a hydrolysis-derivatization step [O’Keeffe et al., 2004] was validated and applied for the simultaneous determination of four of NFMs residues (AHD, AOZ, SEM, AMOZ) in fish samples from aquacultures located in North Western Greece.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:36 to 13:39
Flash presentation in Emerging pollutants

The presence of residual pharmaceuticals in the aquatic environment is an important environmental issue. Since the drugs are designed to cause biological responses, they could pose a risk to organisms in their natural environment. In this study, the presence of selected pharmaceutical compounds (paracetamol, phenazone, ketoprofen, budensonide and atenolol) in surface waters was studied. Six sampling points along the aquatic system of the River Louros, close to the city of Ioannina (Epirus, NW Greece), were selected for the assessment of their pollutant load. Analytical method was based on solid-phase extraction of water samples, using Oasis HLB cartridges, followed by high performance liquid chromatography coupled to Orbitrap high resolution mass spectrometry (UHPLC-LTQ/Orbitrap-MS). The methodology exhibited good analytical characteristics (R>65%, R2 >0.9990, LOQs between 1.5 and 11.0 ng/L). Results revealed the presence of only paracetamol (although in levels below LOQ) in two sampling stations. The proposed analytical methodology proved to be fast, easy and reliable for the systematic monitoring of pharmaceuticals residues in natural waters.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:24 to 13:27
Flash presentation in Emerging pollutants

The biodegradability of fourteen (14) food additives, belonging to different groups such as artificial sweeteners, preservatives and coloring agents, was evaluated using the OECD 301F protocol (manometric respirometry test). According to the results, eight out of fourteen compounds, namely Aspartame, Cyclamate Na, Saccharin, Erythritol, Potassium Sorbate, Benzoic Acid, Sodium Ascorbate and Xylitol are characterized as readily biodegradable with biodegradation rates of 83.6 ± 11.4%, 91.5 ± 5.8%, 76.4 ± 10.3%, 70.6 ± 9.0%, 99.3 ± 7.9%, 97.5 ± 4.0%, 83.8 ± 6.1% and 68.9 ± 2.6%, respectively, during the 28-d experiment. On the other hand, Alitame, Curcumin, Ponceau 4R, Allura Red, Sunset Yellow and Azorubine did not meet the strict definition of ready biodegradability. Further biodegradations tests are required for these compounds in order to investigate their biodegradation potential under different experimental conditions.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:21 to 13:24
Flash presentation in Emerging pollutants

This work aims at integrating the last advances in high resolution mass spectrometry (HRMS) and statistical analysis of data to develop and optimize a smart methodology (workflow) for the assessment of the performance of innovative water treatments using different technological approaches based on advanced oxidation processes with UV-254nm: (i) UV/K2S2O8, where oxidation takes place mainly following the initial formation of sulfate radicals, (ii) UV/KHSO5, where oxidation begins with the formation of both sulfate and hydroxyl radicals and (iii) UV/H2O2, when only the formation of hydroxyl radicals takes place initially.
Experiments were carried out using secondary effluent from a local wastewater treatment plant. The developed workflow allows the evaluation of the treatments in terms of overall oxidation through the careful study of Van Krevelen diagrams, where all the masses of the HRMS chromatograms are considered. The potential formation of transformation products with sulfur due to the sulfate radicals was also evaluated using statistical tools based on the isotopic pattern and accurate mass. Finally, the behavior of a large number of micropollutants with a wide range of physicochemical properties was studied using suspect screening strategies.

Session: 28, Room: D, at Fri, 09/06/2019 - 12:00 to 12:15
Oral presentation in Emerging pollutants

Emerging micro pollutants are substances that have recently been identified in environmental matrices, of which information on environmental permanence and toxicity is still scarce. Due to their chemical structure, antibiotics are more stable and require more complex processes for degradation. The present study aimed to elaborate a proposal for the degradation of the β-lactam antibiotic amoxicillin by photolysis, evaluating the formation of by-products. As a methodology, 100 μg /L amoxicillin solutions were submitted to different ultraviolet light bulbs irradiations, at different power and distances, by means of a 100 mL batch quartz reactor. To evaluation degradation of amoxicillin and of the products generated, the high-performance liquid chromatography-mass spectrometry was used.  As a result, the best degradation condition (greater than 90% reduction of the original molecule) was with a 95W light bulb, at a distance of 5 cm from the sample at 10 min irradiation time. Two by-products originated under different pH conditions of the irradiated solution were identified. Based on the obtained results, it is concluded that this prototype and the applied method can be used in the future to reduce this pollutant.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:18 to 13:21
Flash presentation in Emerging pollutants

A novel laboratory-scale continuous flow wastewater treatment system, consisting of an anaerobic moving bed biofilm reactor (AnMBBR) and an aerobic MBBR, was used for investigating the removal of hydroxybenzothiazole (OH-BTH) and selected benzotriazoles from municipal wastewater. The system was operated under three different Experimental Phases where different organic loadings were applied: 0.82 kg COD m-3 d-1 (Phase A), 0.2 kg COD m-3 d-1 (Phase B) and 2.1 kg COD m-3 d-1 (Phase C). The system achieved sufficient COD removal, nitrification and biogas production. All target micropollutants were partially removed during the experiments. Total removal efficiencies ranged from 32% for 5-methyl-1H-benzotriazole (5TTR) to 97% for OH-BTH. The contribution of the strictly anaerobic bioreactor was important for 5TTR, 5-chlorobenzotriazole (CBTR) and xylytriazole (XTR), while the use of aerobic bioreactors resulted to important increase of target compounds removal and it was exclusively responsible for the removal of OH-BTH and benzotriazole (BTR).

Session: 28, Room: D, at Fri, 09/06/2019 - 12:15 to 12:30
Oral presentation in Emerging pollutants

The present work aims at investigating the effects of chlorine and chloramine-based disinfection processes on organic matter and the formation of disinfection byproducts (DBPs) in drinking water treatment plants (WTPs). For this, water from four water treatment plants with different characteristics in terms of the type of disinfectant used (chlorine or chloramine) and source water type (groundwater, surface water, or artificially recharged groundwater) was analysed before and after the chemical disinfection process. Specific and generic extraction approaches, and target, suspect and non-target screening approaches using advanced mass spectrometry were used and are currently being explored to characterize the different water matrices.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:27 to 13:30
Flash presentation in Emerging pollutants

Per- and polyfluoroalkyl substances (PFAS) are considered emerging contaminants and have been increased their attention due to their distribution in water body. These compounds are acid and characterized by a thermal stability to make them resistant to degradation processes. Activities such as tannery, paper and cardboard production, waterproof cloths, produce wastewater rich in PFAS and heavy metals. The adsorption process is one of the technologies used for the treatment of wastewater and food residues are getting increased attention as bio-adsorbent because they can be found easily as wastes or by-products and at almost no cost. In this work the removal of PFAS was performed by using food waste such as Yerba Mate (YM) as bio-adsorbent. To achieve the mineralization of Heptadecafluorooctanesulfonic acid adopted as model compounds TiO2 photocatalysis tests were performed. The concentration of pollutants was determined by HPLC, UV-VIS and TOC analysis. SEM-EDS, XRD, FT-IR and BET were done to achieve a characterization of the adsorbent material.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:00 to 13:15
Oral presentation in Emerging pollutants

In this study, a comprehensive suspect screening of organic micropollutants (MPs), and some of their transformation products (TPs) and metabolites, was performed in waste, river and coastal waters from the Ebro Delta region (Catalonia, Spain). For this purpose, an automated suspect screening workflow was developed using two analytical steps: (i) identification of suspected compounds using on-line databases; and (ii) semi-quantification of identified compounds by using isotopic labelled standards. Using this strategy, several pollutants were identified comprising pharmaceuticals, pesticides, abused substances, personal care products, industrial chemicals and surfactants of major relevance in Catalonia. Additionally, their occurrence was evaluated along the wastewater-recipient water chain until they reach estuaries and the Mediterranean Sea. The most ecologically relevant compounds detected, that could be considered as suitable markers of wastewater contamination in freshwater and coastal ecosystems, were highlighted. Results reveal that some suspected TPs and metabolites were more ubiquitous than their parent compound and found at similar concentration levels. These results evidence that suspect screening methodologies can be a useful tool for the identification of relevant markers of wastewater contamination.

Session: 28, Room: D, at Fri, 09/06/2019 - 13:15 to 13:18
Flash presentation in Emerging pollutants