This study demonstrates that regulatory databases combined with the latest advances in high resolution mass spectrometry (HRMS) can be efficiently used to prioritize and identify new, potentially ...hazardous pollutants being discharged into the aquatic environment. Of the approximately 23000 chemicals registered in the database of the National Swedish Product Register, 160 potential organic micropollutants were prioritized through quantitative knowledge of market availability, quantity used, extent of use on the market, and predicted compartment-specific environmental exposure during usage. Advanced liquid chromatography (LC)–HRMS-based suspect screening strategies were used to search for the selected compounds in 24 h composite samples collected from the effluent of three major wastewater treatment plants (WWTPs) in Sweden. In total, 36 tentative identifications were successfully achieved, mostly for substances not previously considered by environmental scientists. Of these substances, 23 were further confirmed with reference standards, showing the efficiency of combining a systematic prioritization strategy based on a regulatory database and a suspect-screening approach. These findings show that close collaboration between scientists and regulatory authorities is a promising way forward for enhancing identification rates of emerging pollutants and expanding knowledge on the occurrence of potentially hazardous substances in the environment.
•First study evaluating the impact of OSSFs with respect to the discharge of MPs into surface water•High concentrations of MPs were detected at sites exclusively affected by OSSFs•Different ...composition profiles were observed at sites affected by WWTPs and OSSFs•OSSFs were shown to be a heterogeneous emission sources of MPs•Photodegradation reduced the levels of specific MPs
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One of the main risks associated with effluents from both wastewater treatment plants (WWTPs) and on-site sewage treatment facilities (OSSFs) is the release of micropollutants (MPs) in receiving water bodies. However, the impact of MPs present in the effluents of OSSFs in the aquatic environment has not been studied so far. The current study evaluates the impact of the effluents of OSSFs and small-to-large scale WWTPs on natural waters. The discharge of 74 MPs was assessed including pharmaceuticals, personal care products, pesticides, artificial sweeteners and perfluoroalkyl substances (PFASs). The sampling was carried out within a Swedish catchment and included three sites that are exclusively affected by OSSFs and other sites that are mainly affected by WWTPs or a mixture of sources (7 sites, 28 samples). Results show that although OSSFs serve a much smaller total number of people, the MPs emitted from OSSFs reached the aquatic environment in significant quantities (concentrations of >150ngL−1 of ∑MPs). The composition profiles for sites affected by WWTPs were similar and were dominated by sucralose (27% of the ∑MPs), caffeine (27% of the ∑MPs), lamotrigine (10% of the ∑MPs), desvenlafaxine (5% of the ∑MPs), and diclofenac (4% of the ∑MPs). In contrast, the sites affected by OSSFs showed high variability, exhibiting a different profile from those affected by WWTPs and also from each other, demonstrating that OSSFs are not homogeneous sources of MPs. Some specific compounds, such as diethyltoluamide (DEET) and caffeine, were proportionally much more important at sites affected by OSSFs than at sites affected by WWTPs (representing a much higher percentage of the ∑MPs in the OSSFs). In contrast, PFASs did not show high concentration variation among the different sampling sites and the composition profiles were relatively similar, indicating that these substances follow different routes of entry into the aquatic environment.
There is an increasing need for comparable and harmonized retention times (t R) in liquid chromatography (LC) among different laboratories, to provide supplementary evidence for the identity of ...compounds in high-resolution mass spectrometry (HRMS)-based suspect and nontarget screening investigations. In this study, a rigorously tested, flexible, and less system-dependent unified retention time index (RTI) approach for LC is presented, based on the calibration of the elution pattern. Two sets of 18 calibrants were selected for each of ESI+ and ESI-based on the maximum overlap with the retention times and chemical similarity indices from a total set of 2123 compounds. The resulting calibration set, with RTI set to range between 1 and 1000, was proposed as the most appropriate RTI system after rigorous evaluation, coordinated by the NORMAN network. The validation of the proposed RTI system was done externally on different instrumentation and LC conditions. The RTI can also be used to check the reproducibility and quality of LC conditions. Two quantitative structure–retention relationship (QSRR)-based models were built based on the developed RTI systems, which assist in the removal of false-positive annotations. The applicability domains of the QSRR models allowed completing the identification process with higher confidence for substances within the domain, while indicating those substances for which results should be treated with caution. The proposed RTI system was used to improve confidence in suspect and nontarget screening and increase the comparability between laboratories as demonstrated for two examples. All RTI-related calculations can be performed online at http://rti.chem.uoa.gr/.
•Water quality was evaluated with a panel of health-relevant toxicity bioassays.•Indirect reuse of outlet wastewater did not affect drinking water quality negatively.•Wastewater treatment reduced ...most bioactivities as compared to incoming water.•Nrf2 activity was not markedly increased by chlorination of treated wastewater.•AhR activity increased in pipeline-system and after chlorination treatment.
Indirect potable reuse of wastewater is a practice that is gaining attention, aiming to increase freshwater supplies to meet water scarcity. However, reusing effluent wastewater for drinking water production comes with a paired risk of adverse health effects, due to the potential presence of pathogenic microorganisms and hazardous micropollutants. Disinfection is an established method to reduce microbial hazards in drinking water, but it has been associated with formation of disinfection by-products (DBPs). In this study, we performed an effect-based assessment of chemical hazards in a system wherein a full-scale trial of disinfection by chlorination, of the treated wastewater was performed prior discharge to the reciepient river. The presence of bioactive pollutants was assessed along the entire treatment system, starting from incoming wastewater to finished drinking water at seven sites in and around the Llobregat River in Barcelona, Spain. Samples were collected in two campaigns, with and without applied chlorination treatment (13 mg Cl2/L) to the effluent wastewater. The water samples were analysed for cell viability, oxidative stress response (Nrf2 activity), estrogenicity, androgenicity, aryl hydrocarbon receptor (AhR) activity and activation of NFĸB (nuclear factor kappa-light-chain-enhancer of activated B cells) signaling using stably transfected mammalian cell lines. Nrf2 activity, estrogen receptor activation and AhR activation was detected in all investigated samples. Overall, removal efficiencies were high in both wastewater treatment and drinking water treatment samples for most of the studied endpoints. No increase in oxidative stress (Nrf2 activity) could be attributed to the additional chlorination treatment of the effluent wastewater. However, we found an increase in AhR activity and a reduction of ER agonistic activity after chlorination treatment of effluent wastewater. The bioactivity detected in finished drinking water was considerably lower compared to what was found in effluent wastewater. We could thus conclude that indirect reuse of treated wastewater for drinking water production can be possible without compromising drinking water quality. This study contributed important knowledge in efforts to increase the reuse of treated wastewater as a source for drinking water production.
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This study evaluated the performance of five different sorbents (granular activated carbon (GAC), GAC + Polonite® (GAC + P), Xylit, lignite and sand) for a set of 83 micropollutants (MPs) ...(pharmaceuticals, perfluoroalkyl substances (PFASs), personal care products, artificial sweeteners, parabens, pesticide, stimulants), together representing a wide range of physicochemical properties. Treatment with GAC and GAC + P provided the highest removal efficiencies, with average values above 97%. Removal rates were generally lower for Xylit (on average 74%) and lignite (on average 68%), although they proved to be highly efficient for a few individual MPs. The average removal efficiency for sand was only 47%. It was observed that the MPs behaved differently depending on their physicochemical properties. The physicochemical properties of PFASs (i.e. molecular weight, topological molecular surface area, log octanol water partition coefficient (Kow) and distribution coefficient between octanol and water (log D)) were positively correlated to observed removal efficiency for the sorbents Xylit, lignite and sand (p < 0.05), indicating a strong influence of perfluorocarbon chain length and associated hydrophobic characteristics. In contrast, for the other MPs the ratio between apolar and polar surface area (SA/SP) was positively correlated with the removal efficiency, indicating that hydrophobic adsorption may be a key feature of their sorption mechanisms. GAC showed to be the most promising filter medium to improve the removal of MPs in on-site sewage treatment facilities. However, more studies are needed to evaluate the removal of MPs in field trials.
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•GAC showed significantly higher removal rates in comparison to the other sorbents.•Physicochemical properties of MPs were correlated with their removal efficiencies.•Removal of PFASs was correlated with the molecular weight, surface area and log Kow.•Removal of most MPs was correlated to the ratio between apolar/polar surface area.
Most current bioexposure assessments for UV filters focus on contaminants concentrations in fish from river and lake. To date there is not information available on the occurrence of UV filters in ...marine mammals. This is the first study to investigate the presence of sunscreen agents in tissue liver of Franciscana dolphin (Pontoporia blainvillei), a species under special measures for conservation. Fifty six liver tissue samples were taken from dead individuals accidentally caught or found stranded along the Brazilian coastal area (six states). The extensively used octocrylene (2-ethylhexyl-2-cyano-3,3-diphenyl-2-propenoate, OCT) was frequently found in the samples investigated (21 out of 56) at concentrations in the range 89–782 ng·g–1 lipid weight. São Paulo was found to be the most polluted area (70% frequency of detection). Nevertheless, the highest concentration was observed in the dolphins from Rio Grande do Sul (42% frequency of detection within that area). These findings constitute the first data reported on the occurrence of UV filters in marine mammals worldwide.
•UV filters are found for the first time in urban groundwater.•Leaks from sewage networks are the main source of UV filters in the aquifers studied.•Compounds with anionic properties are more mobile ...in aquifers.•Attenuation of UV filters in the aquifer occurs under different redox conditions.
The occurrence and fate of UV filters (UV F) in an urban aquifer in correlation with (1) the spatial distribution of UV F in Barcelona’s groundwater, (2) the depth of the groundwater sample, (3) the physicochemical properties of the target compounds, (4) the recharge sources, and (5) the redox conditions of the Barcelona aquifers, were studied for the first time. The highest groundwater concentrations and the largest number of detected UV F were observed in an aquifer recharged by a polluted river (around 55ng/L in SAP-4). In contrast, the urbanized areas had lower concentrations (around 20ng/L in MPSP-1). Two pathways can be identified for UV F to enter the aquifers: (1) leakage of row sewage from the sewage network in urbanized areas and (2) wastewater treatment plant (WWTP) effluents discharged into the river. Measured concentrations of UV F were significantly much lower than those estimated from the waste water proportion in groundwater samples suggesting that UV F might undergo transformation processes in both reducing and oxidizing conditions.
The occurrence and spatial distribution of 158 pharmaceuticals and drugs of abuse were studied in seawater of the Eastern Mediterranean Sea (Saronikos Gulf and Elefsis Bay in central Aegean Sea). ...This area is affected by various anthropogenic pressures as it receives the treated wastewater of the greatest Athens area and off-shore input fluxes. This study constitutes the largest one in terms of number of analytes in this environmental compartment. It provides the first evidence on the occurrence of several pharmaceuticals in marine environment including amoxicillin, lidocaine, citalopram or tramadol, among others.
22 samples were collected at three different depths in 9 sampling stations in order to assess the presence and the spatial distribution of the target compounds. A multi-residue method based on solid phase extraction and liquid chromatography coupled to tandem mass spectrometry was developed for the determination of the 158 target substances and validated for seawater sample analysis. 38 out of the 158 target compounds were detected, 15 of them with frequencies of detection equal to or higher than 50%. The highest detected values corresponded to amoxicillin, caffeine and salicylic acid, with concentrations in the range of <5.0–127.8ngL−1; 5.2–78.2ngL−1 and <0.4–53.3ngL−1, respectively. Inputs from the wastewater treatment plant (WWTP) of Athens revealed to be the main source of pollution in the Inner Saronikos Gulf, whereas, other anthropogenic pressures such as contamination from shipping activity, industrial effluents, dredging and/or inputs from land proved to be also relevant. Τhe concentrations of some compounds varied significantly with depth suggesting that currents play an important role in the dilution of the target compounds.
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•This is the largest study of emerging contaminants (158) in seawater.•Thirty eight compounds have been detected.•Amoxicillin, salicylic acid and caffeine showed the highest concentration levels.•Wastewater release proved to be the major source of contamination.
Traditional swine manure treatments are not fully effective in the removal of veterinary drugs. Moreover, they are costly and entail a significant carbon footprint in many cases. Innovative ...biological approaches based on phototrophic microorganisms have recently emerged as promising alternatives to overcome those limitations. This work evaluated the removal of 19 veterinary drugs (i.e., 16 antibiotics, 1 analgesic, 1 anti-parasitic and 1 hormone) from piggery wastewater (PWW) in two open photobioreactors (PBR) operated with a consortium of microalgae-bacteria (AB-PBR) and purple photosynthetic bacteria (PPB-PBR). Multiple hydraulic retention times (HRT), in particular 11, 8 and 4 days, were tested during stage I, II and III, respectively. Ten out of 19 target compounds were detected with inlet drug concentrations ranging from ‘non-detected’ (n.d.) to almost 23,000 ng L−1 for the antibiotic oxytetracycline. Moreover, three of the antibiotics (i.e., enrofloxacin, sulfadiazine and oxytetracycline) were found at concentrations above the analytical linearity range in some or all of the samples under study. AB-PBR supported higher removal efficiencies (REs) than PPB-PBR, except for danofloxacin. Overall, REs progressively decreased when decreasing the HRT. The highest REs (>90%) were observed for doxycycline (95 ± 3%) and oxytetracycline (93 ± 3%) in AB-PBR during stage I. The other drugs, except sulfadimidine that was the most recalcitrant, showed REs above 70% during stage I in the same photobioreactor. In contrast, no removal was observed for danofloxacin in AB-PBR during stage III, sulfadimidine in PPB-PBR during stage III or marbofloxacin in PPB-PBR during the entire experiment.
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•This work assessed the removal of veterinary drugs by phototrophic microorganisms•AB-PBR was more effective than PPB-PBR in the removal, except for danofloxacin•Tetracyclines exhibited the highest removal with up to 90% at HRT of 11 d in AB-PBR.•Sulfadimidine was as the most recalcitrant compound in both PBRs.•Tetracyclines in effluent were >500 ng L−1 due to their high inlet concentrations.
On-site sewage treatment facilities, particularly septic systems combined with soil infiltration, can be an important source of emerging organic contaminants in groundwater and surface water and thus ...represent a significant source of environmental and human exposure. Two infiltration systems in Åre municipality, Sweden, were examined to assess the occurrence of contaminants in groundwater and their fate and transport during infiltration. Groundwater samples, recipient surface water samples, and wastewater samples from septic tanks were collected from 2016 to 2017 covering all climatological seasons. These samples were analysed for a total of 103 contaminants, including pharmaceuticals, personal care products, organic phosphorus flame-retardants, plasticisers, perfluoroalkyl substances, and food additives. Fourteen of 103 contaminants showed 100% detection frequency in groundwater at concentrations in the low ng L−1 to low μg L−1 range. Of the compounds analysed, tris(2‑butoxyethyl) phosphate, sucralose, caffeine, and benzophenone showed high abundancy with maximum concentrations in the μg L−1 range. The data were normalised for dilution using chloride and sucralose as commonly applied tracers; however, the level of sucralose decreased significantly during infiltration and it is thus suboptimal as a sewage water tracer. Large differences between the two infiltration sites were observed in detection frequencies and concentrations in groundwater, which could be attributed to the system design and the contaminant's migration time from release to sampling point. Seasonal variation was observed for selected chemicals, and the more hydrophobic chemicals showed a higher tendency for attenuation, indicating sorption as a major retention mechanism. A moderate environmental risk to aquatic organisms was estimated in adjacent surface water for galaxolide, tris(1‑chloro‑2‑propyl) phosphate, and tris(2‑butoxyethyl) phosphate. Due to this site-dependency and potential environmental risks, further studies are needed on infiltration systems in different settings and on alternative treatment techniques to reduce the contaminant discharge from on-site sewage treatment facilities.
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•Organic contaminants were found in groundwater affected by on-site infiltration.•Attenuation of organic contaminants depended on the site's hydrogeology.•Contaminants with high hydrophobicity and sorption potential showed higher attenuation.•Individual compounds showed significant seasonal variations.•Some contaminants posed a potential risk to organisms in nearby surface water.
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