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1.
Water Res ; 230: 119539, 2023 Feb 15.
Article in English | MEDLINE | ID: mdl-36610182

ABSTRACT

A state-of-the-art wide-scope target screening of 2,362 chemicals and their transformation products (TPs) was performed in samples collected within the Joint Danube Survey 4 (JDS4) performed in 2019. The analysed contaminants of emerging concern (CECs) included three major categories: plant protection products (PPPs), industrial chemicals and pharmaceuticals and personal care products (PPCPs). In total, 586 CECs were detected in the samples including 158 PPPs, 71 industrial chemicals, 348 PPCPs, and 9 other chemicals. A wide-variety of sample matrices were collected including influent and effluent wastewater, groundwater, river water, sediment and biota. Forty-five CECs (19 PPPs, 8 industrial chemicals, 18 PPCPs) were detected at levels above their ecotoxicological thresholds (lowest predicted no-effect concentration (PNEC) values) in one or more of the investigated environmental compartments, indicating potential adverse effects on the impacted ecosystems. Among them 12 are legacy substances; 33 are emerging and qualify as potential Danube River Basin Specific Pollutants (RBSPs). Moreover, the efficiency of the wastewater treatment plants (WWTPs) was evaluated using 20 selected performance indicator chemicals. WWTPs showed effective removal (removal rate ≥80%) and medium removal (removal rate 25-80%) for 6 and 8 of the indicator chemicals, respectively. However, numerous contaminants passed the WWTPs with a lower removal rate. Further investigation on performance of WWTPs is suggested at catchment level to improve their removal efficiency. WWTP effluents are proven to be one of the major sources of contaminants in the Danube River Basin (DRB). Other sources include sewage discharges, industrial and agricultural activities. Continuous monitoring of the detected CECs is suggested to ensure water quality of the studied area.


Subject(s)
Environmental Monitoring , Water Pollutants, Chemical , Rivers/chemistry , Ecosystem , Water Pollutants, Chemical/analysis , Mass Spectrometry , Chromatography, Gas , Pharmaceutical Preparations
2.
Mutagenesis ; 38(1): 21-32, 2023 02 03.
Article in English | MEDLINE | ID: mdl-36367406

ABSTRACT

Environmental studies which aim to assess the ecological impact of chemical and other types of pollution should employ a complex weight-of-evidence approach with multiple lines of evidence (LoEs). This study focused on in situ genotoxicological methods such as the comet and micronucleus assays and randomly amplified polymorphic DNA analysis as one of the multiple LoEs (LoE3) on the fish species Alburnus alburnus (bleak) as a bioindicator. The study was carried out within the Joint Danube Survey 4 (JDS4) at nine sites in the Danube River Basin in the Republic of Serbia. Out of nine sampling sites, two were situated at the Tisa, Sava, and Velika Morava rivers, and three sites were at the Danube River. The three additionally employed LoEs were: SumTUwater calculated based on the monitoring data in the database of the Serbian Environmental Protection Agency (SEPA) (LoE1); in vitro analyses of JDS4 water extracts employing genotoxicological methods (LoE2); assessment of the ecological status/potential by SEPA and indication of the ecological status for the sites performed within the JDS4 (LoE4). The analyzed biomarker responses in the bleak were integrated into the unique integrated biomarker response index which was used to rank the sites. The highest pollution pressure was recorded at JDS4 39 and JDS4 36, while the lowest was at JDS4 35. The impact of pollution was confirmed at three sites, JDS4 33, 40, and 41, by all four LoEs. At other sampling sites, a difference was observed regarding the pollution depending on the employed LoEs. This indicates the importance of implementing a comprehensive weight-of-evidence approach to ensure the impact of pollution is not overlooked when using only one LoE as is often the case in environmental studies.


Subject(s)
Water Pollutants, Chemical , Animals , Water Pollutants, Chemical/toxicity , Water Pollutants, Chemical/analysis , Environmental Monitoring/methods , Serbia , Micronucleus Tests , DNA Damage
3.
Sci Total Environ ; 805: 150253, 2022 Jan 20.
Article in English | MEDLINE | ID: mdl-34818787

ABSTRACT

Siverskyi Donets is the fourth longest river in Ukraine and its ecosystem is heavily affected by numerous agricultural and industrial activities. An impact of the on-going armed military conflicts in the Eastern Ukraine to the overall pollution by the chemicals has been studied. Considering the uncontrolled activities in the catchment due to the conflict, there is a high demand to assess the contamination status of the Siverskyi Donets basin. In this study, the occurrence of the EU Water Framework Directive priority substances, selected physicochemical parameters and wide-range emerging contaminants were investigated in surface water, groundwater, biota and river sediments samples from 13 sampling sites in the river basin. The study included metals, inorganic, non-polar and polar organic contaminants. The wide-scope target screening of 2316 substances and suspect screening of 2219 substances revealed occurrence of 83 compounds in the studied samples. A few industrial chemicals such as plasticizers bisphenol A and DEHP, as well as flame retardant brominated diphenylethers were found to be potentially hazardous to the ecosystem, exceeding the established legacy environmental quality standards (EQS) or the provisional no-effect concentration (PNEC) values. River sediment samples contained traces of long-term banned chemicals such as polychlorinated biphenyls (PCBs) and degradation products of DDT (p,p'-DDD and p,p'-DDE). A simplified risk assessment based on comparison of measured concentration of the detected compounds against their (eco)toxicity threshold values from the NORMAN Ecotoxicology Database has been performed to aid their prioritization in future monitoring and, eventually, establishing the list of Siverskyi Donets River Basin Specific Pollutants. A comparison with the recent similar studies in the Dniester and Dnieper river basins in Ukraine has shown that the overall pollution by chemicals in the Siverskyi Donets basin is significantly lower.


Subject(s)
Groundwater , Water Pollutants, Chemical , Biota , Ecosystem , Environmental Monitoring , Geologic Sediments , Rivers , Water , Water Pollutants, Chemical/analysis
4.
J Multidiscip Healthc ; 14: 3309-3319, 2021.
Article in English | MEDLINE | ID: mdl-34876817

ABSTRACT

INTRODUCTION: Due to increased exposure risk and the potential impact of COVID-19 infection, health care professionals (HCP) are a target group for COVID-19 vaccination. This study aimed to examine the acceptability of COVID-19 vaccines among HCP at the Queen Elizabeth Hospital, Barbados. DESIGN AND METHODS: A cross-sectional survey of HCP was conducted between February 14 and 27, 2021 using an online questionnaire. The questionnaire included demographic information, knowledge of novel coronavirus, intention to accept the COVID-19 vaccination, vaccine literacy (VL), and perceptions and attitudes regarding COVID-19 vaccines. Mean VL scores were calculated. The relationship between socio-demographic variables and vaccine intent was assessed using a multivariable logistic regression model. RESULTS: Of 343 HCPs, 55.1% indicated they would accept the COVID-19 vaccine if it were available; 44.9% expressed hesitancy towards the COVID-19 vaccine. We assessed the impact of socio-demographic factors and previous vaccine behavior on vaccine intent; after adjustment of the multivariable logistic regression model, non-Barbadian nationality and previous flu vaccine uptake were statistically significant predictors of reported intent to take the COVID-19 vaccine. Persons who indicated that they would take the vaccine had a higher mean vaccine literacy score [3.46 95% CI (3.40, 3.52)] than those who were not ready to take the vaccine immediately [3.23 95% CI (3.15, 3.30)]. VL scores were higher among the 29.5% of HCPs who believed vaccines should be mandatory. CONCLUSION: This study highlighted vaccine hesitancy among HCPs in the sole public tertiary hospital of Barbados. As HCP perceptions may help or hinder the campaign to promote vaccine uptake in Barbados, vaccine promotion programs targeting HCPs are needed to ensure the success of the country's COVID-19 vaccination drive.

6.
BMC Public Health ; 21(1): 399, 2021 02 25.
Article in English | MEDLINE | ID: mdl-33632164

ABSTRACT

BACKGROUND: Accurately defining obesity using anthropometric measures that best capture obesity-related risk is important for identifying high risk groups for intervention. The purpose of this study is to compare the association of different anthropometric measures of obesity with 10-year cardiovascular disease (CVD) risk in adults in the Eastern Caribbean. METHODS: Data from the Eastern Caribbean Health Outcomes Research Network (ECHORN) Cohort Study (ECS) were analyzed. The ECS is comprised of adults aged 40 and older residing in the US Virgin Islands, Puerto Rico, Barbados, and Trinidad. 10-year CVD risk was calculated using the American Heart Association (ACC/AHA) ASCVD Risk Algorithm and categorized in the following high-risk groups: > 7.5, > 10, and > 20%. Logistic regression was used to examine associations between four anthropometric measures of obesity (BMI, waist circumference, waist-to-hip ratio, waist-to height ratio) and 10-year CVD risk. RESULTS: Mean age (SD) of participants (n = 1617) was 56.6 years (±10.2), 64% were women, 74% were overweight/obese, and 24% had an ASCVD risk score above 10%. Elevated body mass index (BMI, > 30 kg/m2) and waist circumference were not associated with CVD risk. Elevated waist-to-hip ratio (WHR, > 0.9 men, > 0.85 women) and elevated waist-to-height ratio (> 0.5) were associated with all three categories of CVD risk. Area under the receiver curve was highest for WHR for each category of CVD risk. Elevated WHR demonstrated odds of 2.39, 2.58, and 3.32 (p < 0.0001) for CVD risk of > 7.5, > 10 and > 20% respectively. CONCLUSION: Findings suggest that WHR is a better indicator than BMI of obesity-related CVD risk and should be used to target adults in the Caribbean, and of Caribbean-descent, for interventions.


Subject(s)
Cardiovascular Diseases , Adult , Barbados , Body Mass Index , Cardiovascular Diseases/epidemiology , Cardiovascular Diseases/etiology , Cohort Studies , Female , Humans , Male , Middle Aged , Obesity/epidemiology , Outcome Assessment, Health Care , Puerto Rico , Risk Factors , Trinidad and Tobago , Waist Circumference , Waist-Hip Ratio
7.
Adv Med Educ Pract ; 11: 989-996, 2020.
Article in English | MEDLINE | ID: mdl-33363427

ABSTRACT

BACKGROUND: Technology-enhanced learning includes the adaptive e-learning platform, a data-driven method with computer algorithms, providing customised learning enhancing critical thinking of individual learners. "Firecracker" - an online adaptive e-learning platform, and assessment software, promotes critical thinking, helps prepare students for courses and high-stakes examinations, and evaluates progress relative to co-learners. The objectives of this study were to determine the usage rates of Firecracker, examine the performance of Firecracker formative quizzes, identify the correlation between Firecracker use and performance with that of performance at summative course assessments, and assess students' satisfaction with Firecracker usage. METHODS: Study participants were Year-2 MBBS (Bachelor of Medicine, Bachelor of Surgery) students (n=91) of the Faculty of Medical Sciences, The University of the West Indies, Cave Hill Campus, Barbados. The Firecracker Administrator uploaded quizzes covering basic science content in the Cardiovascular System course. Access, usage, and performance on Firecracker formative quizzes were retrieved from the Firecracker dashboard. A questionnaire sought the views of study participants. RESULTS: Seven sets of quizzes were administered over nine weeks, with weekly student completion rates ranging from 53% to 73%. Mean quiz scores ranged from 52% to 72%. Students completing >4 quiz sessions compared to those completing ≤4 demonstrated significantly better performance in Firecracker quizzes (P<0.01), final examinations (P<0.01) and in-course assessment plus final examination (P<0.05) scores. Correlations between overall Firecracker performance and in-course assessment marks (P<0.05); between total overall Firecracker performance and final examination (P<0.01); and overall Firecracker performance and total course marks (P<0.01) were all significant. Most students (70%) were happy using Firecracker and felt it complemented coursework (78%) and prepared them for course exams (58%) (P<0.01). CONCLUSION: Overall, Firecracker was perceived very positively and welcomed by the students. Students were satisfied with the Firecracker as a formative assessment tool, and its use correlated with improved performance in the course examinations.

9.
Anal Bioanal Chem ; 412(20): 4893-4907, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32347361

ABSTRACT

The quality of the Dniester River Basin has been seriously impacted by the chemicals released by agriculture, industry, and wastewater discharges. To assess its current chemical pollution status, a transboundary monitoring campaign was conducted in May 2019. Thirteen surface water, 13 sediment, and three biota samples were collected and analyzed using generic sample preparation methods for the determination of organic substances by liquid chromatography high-resolution mass spectrometry (LC-HRMS) and metals by inductively coupled plasma mass spectrometry (ICP-MS). Wide-scope target and suspect screening resulted in detection of Water Framework Directive (WFD) priority substances and emerging contaminants, whereas the raw data were stored in NORMAN Digital Sample Freezing Platform (DSFP) for future retrospective screening. Furthermore, risk assessment was performed to prioritize detected substances and propose a draft list of river basin-specific pollutants. All studied metals (As, Hg, Zn, Cu, Cr, Cd, Pb, Ni) were detected in the surface water and sediments. In total, 139 organic contaminants belonging to various chemical classes (pesticides, pharmaceuticals, drugs of abuse, stimulants, sweeteners, industrial chemicals, and their transformation products) were detected. The highest cumulative concentration of contaminants was observed in surface water from the Byk River, a tributary of the Dniester (Moldova). Concentrations of WFD priority substances diuron and mercury and EU Watch List neonicotinoid compounds imidacloprid and thiamethoxam exceeded their environmental quality standards (EQS), whereas concentrations of 23 emerging substances exceeded their predicted no-effect concentration (PNEC) at minimum one site. Emerging contaminants telmisartan, metolachlor, terbuthylazine, and 4-acetamidoantipyrine were prioritized as potential river basin-specific pollutants. Graphical abstract.

10.
Environ Int ; 138: 105597, 2020 05.
Article in English | MEDLINE | ID: mdl-32120059

ABSTRACT

The occurrence of chemical and biological contaminants of emerging concern (CECs) was investigated in treated wastewater intended for reuse in agriculture. An agarose hydrogel diffusion-based passive sampler was exposed to the outlet of a wastewater treatment plant (WWTP) located in Cyprus, which is equipped with membrane bioreactor (MBR). Passive samplers in triplicate were exposed according to a time-series exposure plan with maximum exposure duration of 28 days. Composite flow-proportional wastewater samples were collected in parallel with the passive sampling exposure plan and were processed by solid phase extraction using HORIZON SPE-DEX 4790 and the same sorbent material (Oasis HLB) as in the passive sampler. The analysis of passive samplers and wastewater samples enabled (i) the field-scale calibration of the passive sampler prototype by the calculation of in situ sampling rates of target substances, and (ii) the investigation of in silico predicted transformation products of the four most ecotoxicologically hazardous antibiotics (azithromycin, clarithromycin, erythromycin, ofloxacin). Additionally, the wastewater samples were subjected to the analysis of seven preselected antibiotic resistant genes (ARGs) and one mobile resistant element (int1). All extracts were analyzed for chemicals in a single batch using a highly sensitive method for pharmaceuticals, antibiotics and illicit drugs by liquid chromatography tandem MS/MS (LC-QQQ) and for various other target compounds (2316 compounds in total) by liquid chromatography high-resolution mass spectrometry (LC-HRMS). 279 CECs and all investigated ARGs (except for blaCTX-M-32) were detected, highlighting potential chemical and biological hazards related to wastewater reuse practices. 16 CECs were prioritized following ecotoxicological risk assessment, whereas sul1 and the mobile resistant element (int1) showed the highest abundance. Comprehensive monitoring efforts using novel sampling methods such as passive sampling, wide-scope target screening and molecular analysis are required to assure safe application of wastewater reuse and avoid spread and crop uptake of potentially hazardous chemicals.


Subject(s)
Wastewater , Water Pollutants, Chemical , Agriculture , Environmental Monitoring , Tandem Mass Spectrometry , Water Pollutants, Chemical/analysis
12.
Adv Med Educ Pract ; 10: 387-397, 2019.
Article in English | MEDLINE | ID: mdl-31239801

ABSTRACT

Background: The objective structured clinical examination (OSCE) is the gold standard and universal format to assess the clinical competence of medical students in a comprehensive, reliable and valid manner. The clinical competence is assessed by a team of many examiners on various stations of the examination. Therefore, it is found to be a more complex, resource- and time-intensive assessment exercise compared to the traditional examinations. Purpose: The objective of this study was to determine the final year MBBS students' and OSCE examiners' perception on the attributes, quality, validity, reliability and organization of the Medicine and Therapeutics exit OSCE held at the University of the West Indies (Cave Hill) in June 2017. Methods: At the end of the OSCE, students and examiners were provided with a questionnaire to obtain their views and comments about the OSCE. Due to the ordinal level of data produced by the Likert scale survey, statistical analysis was performed using the median, IQR and chi-square. Results: A total of 52 students and 22 examiners completed the questionnaire. The majority of the students provided positive views regarding the attributes (eg, fairness, administration, structure, sequence, and coverage of knowledge/clinical skills), quality (eg, awareness, instructions, tasks, and sequence of stations), validity and reliability (eg, true measure of essential clinical skills, standardized, practical and useful experiences), and organization (eg, orientation, timetable, announcements and quality of examination rooms) of the OSCE. Similarly, majority of the examiners expressed their satisfaction with organization, administration and process of OSCE. However, students expressed certain concerns such as stressful environment and difficulty level of OSCE. Conclusion: Overall, the OSCE was perceived very positively and welcomed by both the students and examiners. The concerns and challenges regarding OSCE can be overcome through better orientation of the faculty and preparation of the students for the OSCE.

13.
BMC Med Educ ; 19(1): 149, 2019 May 16.
Article in English | MEDLINE | ID: mdl-31096975

ABSTRACT

BACKGROUND: Various evidence-based and student-centered strategies such as team-based learning (TBL), case-based learning (CBL), and flipped classroom have been recently applied to anatomy education and have shown to improve student engagement and interaction. These strategies shift the focus of teaching from knowledge transmission to knowledge construction by students and encourage the use of tasks. This study discusses the use of an active and engaging learning strategy to teach the musculoskeletal system to Year 1 MBBS students (Faculty of Medical Sciences, The University of the West Indies, Cave Hill, Barbados) and examines the correlation between assessment modalities and student performance. METHODS: The "Active and Engaging Learning Strategy" was used to assess student learning in the form of oral presentations. Students had presentations on muscle attachments, muscle actions, blood and nerve supply, and applied anatomy of the limb musculature. Questions on the limbs (Locomotor System) were included in pre and post-presentation spotters, in-course assessments, and final examinations. Percentages, paired t-test, independent sample t-test, and zero-order correlations were performed to confirm the results for the different objectives of the study. RESULTS: The main modes of presentation chosen were poems (37.1%), followed by stories (21.2%), songs (11.4%), and skits (10.6%). The majority of students (84%) found the strategies beneficial and recommended such sessions for future cohorts (92%). Students achieved significantly better scores in post-presentation spotters (p < 0.01) and the marks of in-course and final examinations also showed significant improvement (p < 0.01). CONCLUSION: Our study highlighted that the active and engaging learning strategy can be used as an effective learning tool in anatomy. Students were proactive in preparing the muscle presentations by utilizing their own creativity, curiosity, and intelligence. Further studies should be conducted using randomized controlled trials to assess the effectiveness of various learning strategies which could open a new door to medical education.


Subject(s)
Anatomy/education , Education, Medical, Undergraduate , Problem-Based Learning , Teaching , Anatomy/standards , Educational Measurement , Humans , Program Evaluation , Task Performance and Analysis
14.
Sci Total Environ ; 681: 475-487, 2019 Sep 01.
Article in English | MEDLINE | ID: mdl-31121398

ABSTRACT

Seven-day composite effluent samples from a German monitoring campaign including 33 conventional wastewater treatment plants (WWTP) were analyzed for linear alkylbenzene sulfonates (LAS) and alkyl ethoxysulfates (AES) and were screened by wide-scope suspect screening for 1564 surfactants and their transformation products (TPs) by UHPLC-ESI-QTOF-MS. Corresponding seven-day composite influent samples of selected WWTPs showed high influent concentrations as well as very high removal rates for LAS and AES. However, average total LAS and AES effluent concentrations were still 14.4 µg/L and 0.57 µg/L, respectively. The LAS-byproducts di-alkyl tetralin sulfonates (DATSs), the TPs sulfophenyl alkyl carboxylic acids (SPACs) and sulfo-tetralin alkyl carboxylic acids (STACs) reached maximum effluent concentrations of 19 µg/L, 17 µg/L and 5.3 µg/L, respectively. In many cases the sum of the concentration of all LAS-related byproducts and TPs surpassed the concentration of the precursors. High concentrations of up to 7.4 µg/L were found for 41 polyethylenoglycol homologs. Quantified surfactants and their TPs and by-products together accounted for concentrations up to 82 µg/L in WWTP effluents. To determine the risk of individual surfactants and their mixtures, single homologs were grouped by a "weighted carbon number approach" to derive normalized Predicted No-Effect Concentrations (PNEC), based on experimental ecotoxicity data from existing risk assessments, complemented by suitable Quantitative Structure-Activity Relationships (QSAR) predictions. Predicted Environmental Concentrations (PEC) were derived by dividing effluent concentrations of surfactants by local dilution factors. Risks for all analyzed surfactants were below the commonly accepted PEC/PNEC ratio of 1 for single compounds, while contributions to mixture toxicity effects from background levels of LAS and DATS cannot be excluded. Maximum LAS concentrations exceeded half of its PNEC, which may trigger country-wide screening to investigate potential environmental risks.

15.
Environ Int ; 127: 420-429, 2019 06.
Article in English | MEDLINE | ID: mdl-30959307

ABSTRACT

Averaged 7-day composite effluent wastewater samples from twelve wastewater treatment plants (WWTPs) in nine countries (Romania, Serbia, Hungary, Slovenia, Croatia, Slovakia, Czechia, Austria, Germany) in the Danube River Basin were collected. WWTPs' selection was based on countries' dominant technology and a number of served population with the aim to get a representative holistic view of the pollution status. Samples were analyzed for 2248 chemicals of emerging concern (CECs) by wide-scope target screening employing LC-ESI-QTOF-MS. 280 compounds were detected at least in one sample and quantified. Spatial differences in the concentrations and distribution of the compounds classes were discussed. Additionally, samples were analyzed for the possible agonistic/antagonistic potencies using a panel of in vitro transactivation reporter gene CALUX® bioassays including ERα (estrogenics), anti-AR (anti-androgens), GR (glucocorticoids), anti-PR (anti-progestins), PPARα and PPARγ (peroxisome proliferators) and PAH assays. The potency of the wastewater samples to cause oxidative stress and induce xenobiotic metabolism was determined using the Nrf2 and PXR CALUX® bioassays, respectively. The signals from each of the bioassays were compared with the recently developed effect-based trigger values (EBTs) and thus allowed for allocating the wastewater effluents into four categories based on their measured toxicity, proposing a putative action plan for wastewater operators. Moreover, samples were analyzed for antibiotics and 13 antibiotic-resistant genes (ARGs) and one mobile genetic element (intl1) with the aim to assess the potential for antibiotic resistance. All data collected from these various types of analysis were stored in an on-line database and can be viewed via interactive map at https://norman-data.eu/EWW_DANUBE.


Subject(s)
Anti-Bacterial Agents/analysis , Drug Resistance, Microbial , Rivers/chemistry , Wastewater/chemistry , Biological Assay , Drug Resistance, Microbial/genetics , Water Pollutants, Chemical/analysis
16.
Anal Bioanal Chem ; 411(10): 1957-1977, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30830245

ABSTRACT

Untargeted analysis of a composite house dust sample has been performed as part of a collaborative effort to evaluate the progress in the field of suspect and nontarget screening and build an extensive database of organic indoor environment contaminants. Twenty-one participants reported results that were curated by the organizers of the collaborative trial. In total, nearly 2350 compounds were identified (18%) or tentatively identified (25% at confidence level 2 and 58% at confidence level 3), making the collaborative trial a success. However, a relatively small share (37%) of all compounds were reported by more than one participant, which shows that there is plenty of room for improvement in the field of suspect and nontarget screening. An even a smaller share (5%) of the total number of compounds were detected using both liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). Thus, the two MS techniques are highly complementary. Most of the compounds were detected using LC with electrospray ionization (ESI) MS and comprehensive 2D GC (GC×GC) with atmospheric pressure chemical ionization (APCI) and electron ionization (EI), respectively. Collectively, the three techniques accounted for more than 75% of the reported compounds. Glycols, pharmaceuticals, pesticides, and various biogenic compounds dominated among the compounds reported by LC-MS participants, while hydrocarbons, hydrocarbon derivatives, and chlorinated paraffins and chlorinated biphenyls were primarily reported by GC-MS participants. Plastics additives, flavor and fragrances, and personal care products were reported by both LC-MS and GC-MS participants. It was concluded that the use of multiple analytical techniques was required for a comprehensive characterization of house dust contaminants. Further, several recommendations are given for improved suspect and nontarget screening of house dust and other indoor environment samples, including the use of open-source data processing tools. One of the tools allowed provisional identification of almost 500 compounds that had not been reported by participants.

17.
J Hazard Mater ; 358: 494-502, 2018 09 15.
Article in English | MEDLINE | ID: mdl-29843939

ABSTRACT

Growth inhibition of freshwater microalga Pseudokirchneriella subcapitata caused by a waste water treatment plant (WWTP) effluent extract was investigated using an effect directed analysis (EDA) approach. The objective was to identify compounds responsible for the toxicity by combining state-of-the-art sampling, bioanalytical, fractionation and non-target screening techniques. Three fractionation steps of the whole extract were performed and bioactive fractions were analysed with GC (xGC)-MS and LC-HRMS. In total, 383 compounds were tentatively identified, and their toxicity was characterized using US EPA Ecotox database, open scientific literature or modelled by ECOSAR. Among the top-ranking drivers of toxicity were pesticides and their transformation products, pharmaceuticals (barbiturate derivatives and macrolide antibiotics e.g. azithromycin), industrial compounds or caffeine and its metabolites. Several of the top-ranking pesticides are no longer registered for use in plant protection products or biocides in the Czech Republic (e.g. prometryn, atrazine, acetochlor, resmethrin) and some are approved only for use in biocides (e.g. terbutryn, carbendazim, phenothrin), which indicates that their non-agricultural input into aquatic environment via WWTPs should be carefully considered. The study demonstrated a functional strategy of combining biotesting, fractionation and non-target screening techniques in the EDA study focused on the identification of algal growth inhibitors in WWTP effluent.


Subject(s)
Environmental Monitoring/methods , Growth Inhibitors/toxicity , Microalgae/drug effects , Wastewater/chemistry , Water Pollutants, Chemical/toxicity , Czech Republic , Growth Inhibitors/analysis , Microalgae/growth & development , Water Pollutants, Chemical/analysis
19.
Sci Total Environ ; 601-602: 1849-1868, 2017 Dec 01.
Article in English | MEDLINE | ID: mdl-28629112

ABSTRACT

Growing concern about the adverse environmental and human health effects of a wide range of micropollutants requires the development of novel tools and approaches to enable holistic monitoring of their occurrence, fate and effects in the aquatic environment. A European-wide demonstration program (EDP) for effect-based monitoring of micropollutants in surface waters was carried out within the Marie Curie Initial Training Network EDA-EMERGE. The main objectives of the EDP were to apply a simplified protocol for effect-directed analysis, to link biological effects to target compounds and to estimate their risk to aquatic biota. Onsite large volume solid phase extraction of 50 L of surface water was performed at 18 sampling sites in four European river basins. Extracts were subjected to effect-based analysis (toxicity to algae, fish embryo toxicity, neurotoxicity, (anti-)estrogenicity, (anti-)androgenicity, glucocorticoid activity and thyroid activity), to target analysis (151 organic micropollutants) and to nontarget screening. The most pronounced effects were estrogenicity, toxicity to algae and fish embryo toxicity. In most bioassays, major portions of the observed effects could not be explained by target compounds, especially in case of androgenicity, glucocorticoid activity and fish embryo toxicity. Estrone and nonylphenoxyacetic acid were identified as the strongest contributors to estrogenicity, while herbicides, with a minor contribution from other micropollutants, were linked to the observed toxicity to algae. Fipronil and nonylphenol were partially responsible for the fish embryo toxicity. Within the EDP, 21 target compounds were prioritized on the basis of their frequency and extent of exceedance of predicted no effect concentrations. The EDP priority list included 6 compounds, which are already addressed by European legislation, and 15 micropollutants that may be important for future monitoring of surface waters. The study presents a novel simplified protocol for effect-based monitoring and draws a comprehensive picture of the surface water status across Europe.

20.
Sci Total Environ ; 581-582: 350-358, 2017 Mar 01.
Article in English | MEDLINE | ID: mdl-28062104

ABSTRACT

The implementation of targeted and nontargeted chemical screening analysis in combination with in vitro and organism-level bioassays is a prerequisite for a more holistic monitoring of water quality in the future. For chemical analysis, little or no sample enrichment is often sufficient, while bioanalysis often requires larger sample volumes at a certain enrichment factor for conducting comprehensive bioassays on different endpoints or further effect-directed analysis (EDA). To avoid logistic and technical issues related to the storage and transport of large volumes of water, sampling would benefit greatly from onsite extraction. This study presents a novel onsite large volume solid phase extraction (LVSPE) device tailored to fulfill the requirements for the successful effect-based and chemical screening of water resources and complies with available international standards for automated sampling devices. Laboratory recovery experiments using 251 organic compounds in the log D range from -3.6 to 9.4 (at pH7.0) spiked into pristine water resulted in acceptable recoveries and from 60 to 123% for 159 out of 251 substances. Within a European-wide demonstration program, the LVSPE was able to enrich compounds in concentration ranges over three orders of magnitude (1ngL-1 to 2400ngL-1). It was possible to discriminate responsive samples from samples with no or only low effects in a set of six different bioassays (i.e. acetylcholinesterase and algal growth inhibition, androgenicity, estrogenicity, fish embryo toxicity, glucocorticoid activity). The LVSPE thus proved applicable for onsite extraction of sufficient amounts of water to investigate water quality thoroughly by means of chemical analysis and effect-based tools without the common limitations due to small sample volumes.

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