Aerobic degradation of tetramethyl bisphenol F (TMBPF) with activated sludge: Kinetics and biotransformation products.

This study investigated the bio-degradation kinetics of tetramethyl bisphenol F (TMBPF), a non-estrogenic alternative to bisphenol A (BPA). Batch biotransformation experiments were performed whereby samples were inoculated with activated sludge and analysed using liquid chromatography-Orbitrap-tandem mass spectrometry (LC-Orbitrap-MS) utilising two non-targeted workflows (commercial and freely available online) for biotransformation products (BTP) identification. The degradation of TMBPF followed single first-order reaction kinetics and depended on the initial concentration (ci) with faster degradation -kt = 0.16, (half-life = 4.4 days) at lower concentrations ci = 0.1 mg L-1, compared with -kt = 0.02 (half-live = 36.4 days) at ci = 10.0 mg L-1. After 18 days, only 8% of the original TMBPF remained at the lowest tested concentration (0.1 mg L-1). Twelve BTPs were identified, three of which were workflow and one condition-specific. The highest relative quantities of BTPs were observed in nutrient-mineral and mineral media after ten days, while after 14 days, 36 and 31% of TMBPF (ci = 1 mg L-1) remained in the nutrient-mineral and mineral media, respectively. Also, the kinetics of TMBPF and its BTPs were the same with and without an additional carbon source. A newly proposed biodegradation pathway for TMBPF involves cleavage of the methylene bridge, hydroxylation with further oxidation, sulphation, nitrification, nitro reduction with further oxidation, acetylation, and glycine conjugation, providing a deeper insight into the fate of TMBPF during biological wastewater treatment.

A modified QuEChERS approach for the analysis of pharmaceuticals in sediments by LC-Orbitrap HRMS.

This work reports on a rapid and sensitive analytical method intended to be used for investigation of 25 multiclass pharmaceuticals in sediments. The method comprises a modified quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction, followed by ultra-high-performance liquid chromatography-high-resolution linear ion trap/Orbitrap mass spectrometry, operated in positive ionization mode. The crucial parameters of both extraction and cleanup as well as those related to liquid chromatography and mass spectrometry were optimized and the method was validated in terms of accuracy, method detection and quantification limits, precision, linearity, and matrix effects. A matrix-matched calibration approach and isotopically labeled internal standards were employed for quantification and correction of matrix effects. In the optimized method, recoveries were calculated to be between 64 and 101% in the intermediate spiking level, with a relative standard deviation below 14%. Method quantification limits ranged from 1.3 to 47 ng g-1. The linearity, expressed as a correlation coefficient, was over 0.998 in all cases, within a range from each compound's method quantification limit to 250 ng g-1. The matrix effect study revealed slight signal suppression that decreased after the cleanup step for 50% of the pharmaceuticals, proving its adequacy to limit matrix interferences, without causing any important loss of relevant analytes. The applicability of the method was successfully tested in sediments from two Greek rivers in northwestern Greece, revealing the presence of paracetamol, risperidone, venlafaxine, citalopram, and carbamazepine and estimating for the first time the potential occurrence of pharmaceuticals in these two aquatic systems.

Trace analysis of pesticide residues in sediments using liquid chromatography-high-resolution Orbitrap mass spectrometry.

The present study describes the optimization and validation of an analytical method based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and purification with dispersive solid-phase extraction (dSPE) before analysis, followed by ultrahigh-performance liquid chromatography-high-resolution linear ion trap/Orbitrap (LTQ Orbitrap) mass spectrometry for the determination of 18 pesticides in sediment. To optimize process efficiency, parameters such as pH, extraction salts, sediment amount, and cleanup sorbents were evaluated. Identification was based on both accurate mass and retention time, and further confirmation was achieved by mass spectrometry fragmentation. The optimized analytical method demonstrated good validation characteristics, such as accuracy (recoveries from 70.8% to 106.2%), method quantification limits (below 10 ng g-1 for 89% of the pesticides selected), linearity (coefficient of determination greater than 0.9921 in all cases), precision (repeatability and reproducibility with standard deviations below 18% and 21%, respectively), and matrix effect (signal suppression was exhibited for almost all analytes). The overall method performance, expressed as process efficiency, ranged from 58.8% to 102.1%. The validated method was successfully applied to real samples collected along two rivers in northwestern Greece, revealing the presence of three selected pesticides but at levels below the method quantification limit.

Bioaccumulation of persistent and emerging pollutants in wild sea urchin Paracentrotus lividus.

Marine pollution has been increasing as a consequence of anthropogenic activities. The preservation of marine ecosystems, as well as the safety of harvested seafood, are nowadays a global concern. Here, we report for the first time the contamination levels of a large set of 99 emerging and persistent organic contaminants (butyltins (BTs), polycyclic aromatic hydrocarbons (PAHs), pesticides including pyrethroids, pharmaceuticals and personal care products (PCPs) and flame retardants) in roe/gonads of sea urchin Paracentrotus lividus. Sea urchins are a highly prized worldwide delicacy, and the harvesting of this seafood has increased over the last decades, particularly in South West Atlantic coast, where this organism is harvested mainly for exportation. Sampling was performed in three harvesting sites of the NW Portuguese coast subjected to distinct anthropogenic pressures: Carreço, Praia Norte and Vila Chã, with sea urchins being collected in the north and south areas of each site. Butyltins and pharmaceuticals were not found at measurable levels. Several PAHs, four pyrethroids insecticides, four PCPs and eleven flame retardants were found in roe/gonads of sea urchins, though in general at low levels. Differences among harvesting sites and between areas within each site were found, the lowest levels of contaminants being registered in Carreço. The accumulation of contaminants in sea urchins' roe/gonads seemed to reflect the low anthropogenic pressure felt in the sampling sites. Nevertheless, taking into account the low accumulated levels of chemicals, results indicate that sea urchins collected in South West Atlantic coast are safe for human consumption.

Does climbazole instigate a threat in the environment as persistent, mobile and toxic compound? Unveiling the occurrence and potential ecological risks of its phototransformation products in the water cycle.

Persistent, mobile, and toxic chemicals (PMT), such as the antimycotic climbazole-(CBZ), proliferate in water cycle and imperil drinking water quality, sparking off research about their environmental fate. Unlike the parent compound, its transformation products-(TPs) are scarcely investigated, much less as PMTs. To this end, phototransformation of CBZ was investigated. A novel suspect-screening workflow was developed and optimized by cross-comparing the results of the identified photo-TPs against literature data to create an enhanced HRMS-database for environmental investigations of CBZ/TPs in the water cycle. In total, 24 TPs were identified, 14 of which are reported for the first time. Isomerism, dechlorination, hydroxylation, and cleavage of the ether or C-N bond are suggested as the main transformation routes. A screening of CBZ/TPs was conducted in wastewater, leachates, surface, and groundwater, revealing a maximum concentration of 464.8 ng/L in groundwater. In silico and in vitro methods were used for toxicity assessment, indicating toxicity for CBZ and some TPs. Seemingly, CBZ is rightly considered as PMT, and a higher potential to occur in surface or groundwater than non-PM chemicals appears. Likewise, the occurrence of TPs due to PMT properties or emission patterns was evaluated.

Photo-assisted transformation of furosemide: Exploring transformation pathways, structure database and suspect and non-target workflows for comprehensive screening of unknown transformation products in wastewaters and landfill leachates.

In recent years, transformation products-(TPs) of pharmaceuticals in the environment have received considerable attention. In this context, here, a customized overview of transformation of Furosemide-(FRS) in aqueous matrices treated by photo-oxidation is provided as a proof of concept. Hence, the primary goal of the study was to display an integrated strategy by combining the target (parent-molecule) and suspect screening-(SS) approaches (TPs) in order to build an in-house High-Resolution mass spectrometry (HRMS) database able to provide reference information (chromatographic/spectral) for environmental investigations in complex matrices (wastewaters/landfill leachates). Data analysis was performed by optimizing a SS workflow. Additional confirmation for the proposed structural elucidation was provided by correlating retention time to the proposed structure employing three prediction models. This approach was applied for the tentative identification of 35 TPs of FRS, 28 of which are reported herein for the first time. Finally, SS and non-target analysis (NTA) have been successfully applied for retrospective screening of FRS and its TPs in real samples. The findings demonstrated that SS allows the proper identification of TPs of FRS in complex matrices proving its outstanding importance compared to NTA. In total, six TPs were identified by SS with potential ecotoxicological implications for two of them according to in silico risk assessment.

Degradation and toxicity of bisphenol A and S during cold atmospheric pressure plasma treatment.

Bisphenols are widely recognised as toxic compounds that potentially threaten the environment and public health. Here we report the use of cold atmospheric pressure plasma (CAP) to remove bisphenol A (BPA) and bisphenol S (BPS) from aqueous systems. Additionally, methanol was added as a radical scavenger to simulate environmental conditions. After 480 s of plasma treatment, 15-25 % of BPA remained, compared to > 80 % of BPS, with BPA being removed faster (-kt = 3.4 ms-1, half-life = 210 s) than BPS (-kt = 0.15 ms-1, half-life 4700 s). The characterisation of plasma species showed that adding a radical scavenger affects the formation of reactive oxygen and nitrogen species, resulting in a lower amount of ˙OH, H2O2, and NO2- but a similar amount of NO3-. In addition, a non-target approach enabled the elucidation of 11 BPA and five BPS transformation products. From this data, transformation pathways were proposed for both compounds, indicating nitrification with further cleavage, demethylation, and carboxylation, and the coupling of smaller bisphenol intermediates. The toxicological characterisation of the in vitro HepG2 cell model has shown that the mixture of transformation products formed during CAP is less toxic than BPA and BPS, indicating that CAP is effective in safely degrading bisphenols.

Overarching issues on relevant pesticide transformation products in the aquatic environment: A review.

The intensification of agricultural production during the last decades has forced the rapid increase in the use of pesticides that finally end up in the aquatic environment. Albeit well-documented, pesticides continue to raise researchers' attention, because of their potential adverse impacts on the environment and, inevitably, humans. Once entering the aquatic bodies, pesticides undergo biotic and abiotic processes, resulting in transformation products (TPs) that sometimes are even more toxic than the parent compounds. A substantial shift of the scientific interest in the TPs of pesticides has been observed since their environmental fate, occurrence and toxicity is still in its formative stage. In an ongoing effort to expand the existing knowledge on the topic, several interesting works have been performed mostly in European countries, such as France, Germany, Italy, Switzerland, Greece, and Spain that counts the highest number of relevant publications. Pesticide TPs have been also studied to a lesser extent in Asia, North and South America. To this end, the main objective of this review is to delineate the global occurrence, fate, toxicity as well as the analytical challenges related to pesticide TPs in surface, ground, and wastewaters, with the view to contribute to a better understanding of the environmental problems related with TPs formation. The concentration levels of the TPs, ranging from the low ng/L to high µg/L scale and distributed worldwide. Ultimately, an attempt to predict the acute and chronic toxicity of TPs has been carried out with the aid of an in-silico approach based on ECOSAR, revealing increased chronic toxicity for the majority of the identified TPs, despite the change they underwent, while a small portion of them presented serious acute toxicity values.

Assessment of a wide array of organic micropollutants of emerging concern in wastewater treatment plants in Greece: Occurrence, removals, mass loading and potential risks.

Exploring the contamination profile of multi-class emerging contaminants (ECs) in wastewater is highly desirable. To this end, the occurrence, removal, mass loading and risks associated with a large panel of pharmaceuticals and personal care products, illicit drugs, perfluorinated compounds and organophosphate flame retardants in two wastewater treatment plants (WWTPs) in the region of Thessaloniki (Greece) after a survey is illustrated. Influent and effluent wastewaters were submitted to solid phase extraction on Oasis HLB cartridges, followed by ultra-high-performance liquid chromatography Orbitrap high-resolution mass spectrometry (UHPLC-Orbitrap MS). Influent concentrations in both WWTPs were notably higher than effluent, with caffeine, acetaminophen, irbesartan and valsartan being the most ubiquitous compounds, exhibiting elevated concentrations. Average effluent concentrations ranged from below the method quantification limits (80% in both WWTPs, allowing the correlation between logKow and removals. Interesting trends for the illicit drugs were revealed by means of mass loading estimation, as in the case of benzoylecgonine (71.6 mg/day/1000 inhabitants). Ecotoxicological risk assessment was evaluated for both single components and mixture, using three approaches: risk quotient (RQ), risk quotient considering frequency (RQf) and toxic units (TU). Irbesartan and telmisartan posed a high risk in all trophic levels, while fish was the most sensitive taxa for diclofenac. This work aspires to intensify the surveillance programs for the receiving water bodies, as well as to motivate the investigation of toxicity to non-target organisms.

Screening of pesticides and emerging contaminants in eighteen Greek lakes by using target and non-target HRMS approaches: Occurrence and ecological risk assessment.

Lakes, albeit ecosystems of vital importance, are insufficiently investigated with respect to the degradation of water quality due to the organic micropollutants load. As regards Greece, screening of lake waters is scarce and concerns a limited number of contaminants. However, understanding the occurrence of contaminants of emerging concern (CECs) and other micropollutants in lakes is essential to appraise their potential ecotoxicological effects. The aim of this study was to deploy a multiresidue screening approach based on liquid chromatography-high-resolution mass spectrometry (HRMS) to get a first snapshot for >470 target CECs, including pesticides, pharmaceuticals, personal care products (PPCPs), per- and polyfluoroalkyl substances (PFASs), as well as organophosphate flame retardants (OPFRs) in eighteen Greek lakes in Central, Northern and West Northern Greece. The omnipresent compounds were DEET (N,N-diethyl-meta-toluamide), caffeine and TCPP (tris (1-chloro-2-propyl) phosphate). Maximum concentrations varied among the different classes. DEET was detected at a maximum average concentration of >1000 ng/L in Lake Orestiada, while its mean concentration was estimated at 233 ng/L. The maximum total concentrations for pesticides, PPCPs, PFASs, and OPFRs were 5807, 2669, 33.1, and 1214 ng/L, respectively, indicating that Greek lakes are still threatened by the intense agricultural activity. Besides, HRMS enabled a non-target screening by exploiting the rich content of the full-scan raw data, allowing the 'discovery' of tentative candidates, such as surfactants, pharmaceuticals, and preservatives among others, without reference standards. The potential ecotoxicity was assessed by both the risk quotient method and ECOSAR (Ecological Structure Activity Relationships) revealing low risk for most of the compounds.

HRMS screening of organophosphate flame retardants and poly-/perfluorinated substances in dust from cars and trucks: Occurrence and human exposure implications.

Time spent within vehicles' cabin has been largely increased during the last years. As a result, the assessment of indoor dust quality is meaningful since dust can be a source of numerous emerging contaminants associated with adverse effects in human health. To this end, fourteen cars and ten trucks from the city of Thessaloniki, Northern Greece were selected to assess the quality of vehicles' microenvironments. An HRMS-based strategy was deployed for the target and non-target analysis of the collected samples. The target approach aimed at the accurate mass screening of nine organophosphate flame retardants (OPFRs) and nine per-/polyfluorinated compounds (PFAS), revealing mean concentrations for the OPFRs varied from

Chemical characterization of riverine sediments affected by wastewater treatment plant effluent discharge.

This study was aimed at assessing the contribution of wastewater treatment effluents to the contamination profile of the sediments of receiving waterways. Three wastewater treatment plants (WWTP) were addressed, encompassing different population equivalent sizes, urbanization degrees and treatment methods translating differences in expected contamination patterns. Within each WWTP system, the assessment targeted the effluent and sediment samples collected upstream and downstream the effluent discharge point; contaminants belonging to several concerning chemical classes (metals and metalloids; pesticides; pharmaceuticals and personal care products, PPCPs; and polycyclic aromatic hydrocarbons, PAHs) were quantified both in effluent and sediment samples. Clear associations between contaminants present in the effluent and corresponding sediment samples were not always verified. In fact, a noticeable difference between the number or abundance of contaminants detected in effluents and in sediments, suggesting that effluents are not always the most likely source (e.g. PAHs). However, sediment contaminants that were likely sourced by the effluents were also identified (e.g. PPCPs). Sediment analysis offers an important historical view of contamination, especially in flowing recipient ecosystems where any characterization over the water matrix is ephemeral and linking exclusively to the moment of sampling. Hence, sediments should be considered for the establishment of WWTP operational benchmarks regulating the emission of contaminants, which is currently focused mostly on effluent composition thus potentially over/underestimating the longer-term impact of effluent discharge in the recipient waterways.

Pharmaceuticals and other contaminants of emerging concern in Admiralty Bay as a result of untreated wastewater discharge: Status and possible environmental consequences.

Considering how the impact of human activity in Antarctica is growing, the aim of this study was to conduct the first assessment of pharmaceuticals and personal care products (PPCPs), other emerging contaminants (ECs), and antibiotic resistance genes present in the western shore of the Admiralty Bay region of King George Island. In total, more than 170 substances were evaluated to assess the potential environmental risks they pose to the study area. The major evaluated source of pollutants in this study is discharged untreated wastewater. The highest PPCP concentrations in wastewater were found for naproxen (2653 ngL-1), diclofenac (747 ngL-1), ketoconazole (760 ngL-1), ibuprofen (477 ngL-1) and acetaminophen (332 ngL-1). Moreover, the concentrations of benzotriazole (6340 ngL-1) and caffeine (3310 ngL-1) were also high. The Risk Quotient values indicate that azole antifungals (ketoconazole), anti-inflammatories (diclofenac, ibuprofen) and stimulants (caffeine) are the main groups responsible for the highest toxic burden. In addition, antibiotic resistance genes integrons (int 1) and sulphonamide resistance genes (sul 1-2) were detected in wastewater and seawater. These results indicate that regular monitoring of PPCPs and other ECs is of great importance in this environment. Additionally, the following mitigation strategies are suggested: (1) to create a centralised record of the medications prescribed and consumed in situ (to improve knowledge of potential contaminants without analysis); (2) to use more environmentally friendly substitutes both for pharmaceuticals and personal care products when possible (limiting consumption at the source); and (3) to apply advanced systems for wastewater treatment before discharge to the recipient (end-of-pipe technologies as a final barrier).

Root-associated bacteria modulate the specialised metabolome of Lithospermum officinale L.

Bacteria influence plant growth and development and therefore are attractive resources for applications in agriculture. However, little is known about the impact of these microorganisms on secondary metabolite (SM) production by medicinal plants. Here we assessed, for the first time, the effects of bacteria on the modulation of SM production in the medicinal plant Lithospermum officinale (Boraginaceae family) with a focus on the naphthoquinones alkannin/shikonin and their derivatives (A/Sd). The study was conducted in an in vitro cultivation system developed for that purpose, as well as in a greenhouse. Targeted and non-targeted metabolomics were performed, and expression of the gene PGT encoding for a key enzyme in the A/S biosynthesis pathway was evaluated with qPCR. Three strains, Chitinophaga sp. R-73072, Xanthomonas sp. R-73098 and Pseudomonas sp. R-71838 induced a significant increase of A/Sd in L. officinale in both systems, demonstrating the strength of our approach for screening A/Sd-inducing bacteria. The bacterial treatments altered other plant metabolites derived from the shikimate pathway as well. Our results demonstrate that bacteria influence the biosynthesis of A/Sd and interact with different metabolic pathways. This work highlights the potential of bacteria to increase the production of SM in medicinal plants and reveals new patterns in the metabolome regulation of L. officinale.

Sample preparation optimization by central composite design for multi class determination of 172 emerging contaminants in wastewaters and tap water using liquid chromatography high-resolution mass spectrometry.

Multi-residue analysis is highly desirable for water quality control. To this end, a comprehensive workflow for the quantitative analysis of 172 anthropogenic organic compounds belonging to emerging contaminants (pharmaceuticals and personal care products, illicit drugs, organophosphate flame retardants and perfluoroalkyl substances) has been developed for application to wastewater and tap water, based on solid phase extraction (SPE) and Orbitrap high resolution mass spectrometry (HRMS). Due to the large number of analytes with various physicochemical characteristics that should be efficiently extracted, the response surface methodology (RSM) employing a central composite design (CCD) and desirability function (DF) approach was exploited to optimize the sample preparation process, instead of the conventional single-factor analysis. The factors included in the design of experiments (DoE) were sample pH, eluent solvents composition and volume. Statistical analysis (ANOVA) proved the adequacy of the proposed model (2- factor interaction) as p-value < 0.05 followed by different diagnostic tests confirmed the good fitting. The best values to acquire DF close to 1 were pH 3.5, methanol/ethyl acetate ratio 87:13 and eluent volume 6 mL. The streamlined method was validated in terms of accuracy, linearity, method limits, reproducibility, and matrix effect. The proposed workflow combines sensitivity and robustness, with recoveries over 70%, method quantification limits <1 ng/L, and relative standard deviations <20% for most of the compounds. Slight matrix effect (ME) was observed for most of PPCPs, IDs and PFAs, in contrast with most of the OPFRs, for which strong ME was calculated. Method applicability was tested over wastewater collected from a municipal wastewater treatment plant in Thessaloniki (Greece), revealing the presence of 69 and 40 compounds in influents and effluents, respectively, at varying concentrations.

Exploring the phototransformation and assessing the in vitro and in silico toxicity of a mixture of pharmaceuticals susceptible to photolysis.

The present study comprehensively investigates the phototransformation and ecotoxicity of a mixture of twelve pharmaceutically active compounds (PhACs) susceptible to photolysis. Namely, three antibiotics (ciprofloxacin, levofloxacin, moxifloxacin), three antidepressants (bupropion, duloxetine, olanzapine), three anti-inflammatory drugs (diclofenac, ketoprofen, nimesulide), two beta-blockers (propranolol, timolol) and the antihistamine ranitidine were treated under simulated solar irradiation in ultra-pure and river water. A total of 166 different transformation products (TPs) were identified by ultra-high performance liquid chromatography coupled with Orbitrap high resolution mass spectrometry (UHPLC-Orbitrap HRMS), revealing the formation of twelve novel TPs and forty-nine not previously described in photolytic studies. The kinetic profiles of the major TPs resulting from a series of chemical reactions involving hydroxylation, cleavage and oxidation, dehalogenation, decarboxylation, dealkylation and photo substitution have been investigated and the transformation pathways have been suggested. Additionally, an in vitro approach to the toxicity assessment of daphnids was contrasted with ecotoxicity data based on the Ecological Structure Activity Relationships (ECOSAR) software comprising the in silico tool to determine the adverse effects of the whole mixture of photolabile parent compounds and TPs. The results demonstrated that photolysis of the target mixture leads to a decrease of the observed toxicity.

First report of detection of microcystins in farmed mediterranean mussels Mytilus galloprovincialis in Thermaikos gulf in Greece.

BACKGROUND: Microcystins are emerging marine biotoxins, produced by potentially toxic cyanobacteria. Their presence has been reported in aquatic animals in Greek freshwater, while data are few in marine environments. Since the climate change induces eutrophication and harmful algal blooms in coastal marine ecosystems affecting the public health, further research on microcystins' presence in marine waters is required. The aim of this study was to examine the potential presence of microcystins in mussels Mytilus galloprovincialis in the largest farming areas in Thermaikos gulf, in Northern Greece, and to investigate their temporal and spatial distribution, adding to the knowledge of microcystins presence in Greek Mediterranean mussels. RESULTS: A 4-year microcystins' assessment was conducted from 2013 to 2016, in farmed Mediterranean mussels M. galloprovincialis, in five sampling areas in Thermaikos gulf, in northern Greece, where the 90% of the Greek mussels' farming activities is located. The isolation of potentially toxic cyanobacteria was confirmed by molecular methods. An initial screening was performed with a qualitative and quantitative direct monoclonal (DM) ELISA and results above 1 ng g-1 were confirmed for the occurrence of the most common microcystins-RR, -LR and -YR, by Ultra High Performance Liquid Chromatography (UHPLC) coupled with a high- resolution mass spectrometer (HRMS) (Orbitrap analyzer). Microcystin-RR and microcystin-LR were detected, while the intensity of microcystin-YR was below the method detection limit. Most samples that exhibited concentrations above 1 ng g-1 were detected during the warm seasons of the year and especially in spring. Results indicated an overestimation of the ELISA method, since concentrations ranged between 0.70 ± 0.15 ng g-1 and 53.90 ± 3.18 ng g-1, while the confirmation denoted that the levels of microcystins were 6 to 22 times lower. CONCLUSIONS: Microcystin-RR and microcystin-LR were detected for the first time in mussel M. galloprovincialis, harvested from farms in Thermaikos gulf, in Central Macedonia, Greece. Their presence was linked to potentially toxic cyanobacteria. Bioaccumulation was observed in digestive gland, while the concentrations in muscles were found extremely low. Samples with levels above 1 ng g-1 were observed mostly during spring, confirming the seasonal distribution of microcystins. The comparison of the results by the ELISA and the LC-Orbitrap MS method indicated an overestimation of concentration by the ELISA method.

Antiviral drugs in aquatic environment and wastewater treatment plants: A review on occurrence, fate, removal and ecotoxicity.

The environmental release of antiviral drugs is of considerable concern due to potential ecosystem alterations and the development of antiviral resistance. As a result, interest on their occurrence and fate in natural and engineered systems has grown substantially in recent years. The main scope of this review is to fill the void of information on the knowledge on the worldwide occurrence of antiviral drugs in wastewaters and natural waters and correlate their levels with their environmental fate. According to the conducted literature survey, few monitoring data exists for several European countries, such as Germany, France, and the UK. Lesser data are available for Asia, where approximately 80% of the studies focus on Japan. Several articles study the occurrence of mostly antiretroantivirals in sub-Saharan African countries, while there is a lack of data for other developing regions of the world, including the rest of Africa, South America, and the biggest part of Asia. An importantly smaller number of studies exists for North America, while no studies exist for Oceania. The against innfluenza drug oseltamivir along with its active carboxy metabolite is found to be the most studied antiviral drug. The distribution of antiviral drugs across all geographic regions varies from low ng L-1 to high µg L-1 levels, in some cases, even in surface waters. This overarching review reveals that monitoring of antiviral drugs is necessary, and some of those compounds may require toxicological attention, in the light of either spatial and temporal high concentration or potential antiviral resistance. Based on the information provided herein, the need for a better understanding of the water quality hazards posed by antiviral drugs existence in wastewater outputs and freshwater ecosystems is demosntrated. Finally, the future challenges concerning the occurrence, fate, and potential ecotoxicological risk to organisms posed by antiviral drug residues are discussed.

Pesticide residues evaluation of organic crops. A critical appraisal.

In the last decade, the consumption trend of organic food has increased dramatically worldwide. Since only a few pesticides are authorized in organic crops, concentrations are expected to range at zero or ultra-trace levels. In this context, the aim of the present study was to investigate the need for an improvement in the residue controls at very low concentrations (<0.010 mg kg-1) and to assess the impact of the scope of the analytical methods for this type of crops. For that purpose, a monitoring study for fruit and vegetable samples covering a wide range of pesticides (3 2 8) at low LOQs (0.002-0.005 mg kg-1) was developed. The results showed that the impact of applying analytical methods with low LOQs was not very relevant in the majority of the cases. However, a wide scope presented a high influence on this evaluation, especially regarding the inclusion of very polar compounds and metabolites.

New insights into transformation pathways of a mixture of cytostatic drugs using Polyester-TiO2 films: Identification of intermediates and toxicity assessment.

The photocatalytic activity of two bio-based polymer photocatalysts [poly(ethylene terephthalate)-TiO2 (PET-TiO2) and poly(L-lactic acid)-graphene oxide-TiO2 (PLLA-GO-TiO2)] towards Tamoxifen (TAM), Cyclophosphamide (CP), Cytarabine (CYT) and 5-Fluorouracil (5-FLU) removal was explored and compared. The highest photocatalytic activity for the degradation of the cytostatic drugs was accomplished by PET-TiO2. Among the contaminants, TAM was the most easily removed, requiring 90 min for complete elimination, while CP showed the highest resistance to photocatalysis, not being completely removed after 6 h. Liquid chromatography coupled with high-resolution mass spectrometry analysis was employed for the identification of several transformation products (TPs) and potential pathways were proposed. A total of seventy (70) TPs including thirty-four (34) novel ones detected in AOPs were identified. The ecotoxicity of the mixture of the cytostatic drugs and TPs formed during the photocatalytic treatment was evaluated using Daphnia magna assay and was associated with the occurrence of specific TPs during the treatment process. The follow-up ECOSAR (Ecological Structure Activity Relationship) analysis further elucidated that only minor chemical transformations, such as the hydroxylation or the oxidative opening of an aromatic ring system, could hamper the adverse effects of cytostatic drugs in aquatic species. Such a comparative study on the mixture toxicity of cytostatics and their TPs is presented for the first time.