Occurrence of high production volume chemicals and polycyclic aromatic hydrocarbons in urban sites close to industrial areas. Human exposure and risk assessment.

Evaluating the occurrence of high production volume chemicals (HPVCs) and polycyclic aromatic hydrocarbons (PAHs) in the air is important because they carry a carcinogenic risk and can lead to respiratory or endocrine problems. Examples of HPVCs are organophosphate esters, benzosulfonamides, benzothiazoles, phthalate esters (PAEs), phenolic antioxidants and ultraviolet stabilizers. In this paper we develop a multi-residue method for determining HPVCs and PAHs in air samples via pressurized liquid extraction followed by gas chromatography-mass spectrometry. Air samples were collected by active sampling with high volume samplers using quartz fiber filter for the particulate matter (PM10) and polyurethane foams for gas phase. The compounds found at the highest concentrations were PAEs, with a concentration of up to 24 ng m-3 of DEHP in gas phase and up to 109 ng m-3 of DEHA in PM10. Non-carcinogenic risk assessment results ranged from 9.7E-05 to 9.5E-03 for most of the compounds studied. On the other hand, the results for carcinogenic risk showed that PAHs made the highest contribution.

Optimization of the ultrasound-assisted extraction method for determining high production volume chemicals in fish liver and skin samples.

The aquatic ecosystem is one of the most delicate environments, housing a diverse range of organisms, including fish, all of which are exposed to a wide variety of pollutants. The accumulation of these harmful substances in fish, which are part of the human diet, presents a significant health risk to humans. In our study, we have optimized an extraction technique to determine the presence of 25 high production volume chemicals in liver and skin samples taken from commonly consumed fish species. We have employed ultrasound-assisted extraction in conjunction with gas chromatography tandem mass spectrometry to achieve this goal. Apparent recoveries of the method ranged from 50% to 111% for both sample types with some exceptions such as most of the benzosulfonamides and benzothiazole. Additionally, the method's detection and quantification limits varied from 0.1 to 1.7 ng g-1 (dry weight, d.w) and 0.2-4.5 ng g-1 (d.w), respectively. Our investigation focused on three frequently consumed fish species in Tarragona: sea bass, sea bream, and turbot. Almost all of the samples we analysed contained traces of contaminants, with phthalates being the most commonly detected. The highest concentrations were observed for diethyl phthalate, with levels peaking at 8350 ng g-1 (d.w.). Organophosphate esters, such as triethyl phosphate and tributyl phosphate, also showed notable presence, with peak concentrations of 93.6 and 34.0 ng g-1 (d.w.), respectively.

Selective determination of 2-aminobenzothiazole in environmental water and organic extracts from fish and dust samples.

In the present study, a homemade mixed-mode ion-exchange sorbent based on silica with embedded graphene microparticles is applied for the selective extraction of 2-aminobenzothiazole (NH2BT) followed by determination through liquid chromatography coupled to high-resolution mass spectrometry. The sorbent was evaluated for the solid-phase extraction of NH2BT from environmental water samples (river, effluent wastewater, and influent wastewater), and NH2BT was strongly retained through the selective cation-exchange interactions. Therefore, the inclusion of a clean-up step of 7 mL of methanol provided good selectivity for the extraction of NH2BT. The apparent recoveries obtained for environmental water samples ranged from 62 to 69% and the matrix effect from -1 to -14%. The sorbent was also evaluated in the clean-up step of the organic extract for the extraction of NH2BT from organic extracts of indoor dust samples (10 mL of ethyl acetate from pressurized liquid extraction) and fish (10 mL of acetonitrile from QuEChERS extraction). The organic extracts were acidified (adding a 0.1% of formic acid) to promote the cation-exchange interactions between the sorbent and the analyte. The apparent recoveries for fish samples ranged from 22 to 36% depending on the species. In the case of indoor dust samples, the recovery was 41%. It should be highlighted the low matrix effect encountered in such complex samples, with values ranging from -7 to 5% for fish and dust samples. Finally, various samples were analyzed. The concentration in river samples ranged from 31 to 136 ng/L; in effluent wastewater samples, from 55 to 191 ng/L; in influent wastewater samples, from 131 to 549 ng/L; in fish samples, from 14 to 57 ng/g dried weight; and in indoor dust samples, from

Evaluation of ceramic passive samplers using a mixed-mode strong cation-exchange sorbent to monitor polar contaminants in river water.

Although most of the analytical methods developed for the monitoring of contaminants in environmental waters are based on discrete grab sampling, an alternative of increasing interest is the use of passive sampling. Methods based on passive sampling provide the sampling and pre-concentration of the analytes in-situ, which makes the sample treatment less time consuming and costly than using discrete grab sampling. In this study, ceramic passive samplers (CPSs) using mixed-mode strong cation-exchange sorbent (Oasis MCX) as retention phase were evaluated for the determination of a group of 21 therapeutic and illicit drugs and some of their metabolites in river water samples that were determined by liquid chromatography-tandem mass spectrometry. After assessing the stability of the analytes, the CPSs were calibrated for 9 days with bottled water and river water, obtaining, for the 19 stable compounds, sample rates (Rs) ranging between 0.180 and 1.767 mL/day and diffusion coefficients (De) between 2.02E-8 and 2.81E-7 cm2/s. Once calibrated, CPSs were deployed for the determination of contaminants in the Ebre River, with good reproducibility, and some of the analytes were determined, including amongst others, gabapentin at 76 ng/L, caffeine at 203 ng/L or diclofenac amine at 57 ng/L. The passive sampling method herein presented is simple and feasible and allows the time-integrated analysis of pharmaceuticals and drugs at trace levels in river water. This study opens the possibility of using other mixed-mode sorbents or other types of sorbents as retaining phase on CPSs for the determination of very polar contaminants in water.

Ceramic passive samplers for determining pharmaceuticals and drugs of abuse in river and drinking water.

An important challenge today is to efficiently monitor the presence of polar pharmaceuticals and drugs in surface and drinking waters to ensure its safeness. Most studies rely on grab sampling techniques, which enable the determination of contaminants at a given point and given time. In this study, we propose the use of ceramic passive samplers (CPSs) to increase the representativeness and efficiency of organic contaminant monitoring in waters. Firstly, we have assayed the stability of 32 pharmaceuticals and drugs and found that five of those compounds were unstable. Moreover, we evaluated the retention capabilities of three sorbents (Sepra ZT, Sepra SBD-L, and PoraPak Rxn RP) in solid-phase extraction (SPE) mode and found no differences in terms of recoveries for all three sorbents. We then calibrated CPSs using the three sorbents for the 27 stable compounds over 13 days, with a suitable uptake for 22 compounds with sampling rates between 0.4 and 17.6 mL/day, which indicates high uptake efficiency. CPSs with the Sepra ZT sorbent were deployed in river water (n = 5) and drinking water (n = 5) for 13 days. Some of the studied compounds occurred with a time-weighted concentration, for instance, of 43 ng/L for caffeine, 223 ng/L for tramadol or 175 ng/L for cotinine in river water.

Seafood consumption as a source of exposure to high production volume chemicals: A comparison between Catalonia and the Canary Islands.

Seafood plays an important role in diet because of its health benefits. However, the fact that chemical compounds such as high production volume chemicals may be present in seafood means that its consumption can be a potential risk for population. To assess the occurrence of HPVs and estimate the exposure and risk associated with their consumption, specimens of the most consumed seafood species in Catalonia and the Canary Islands, Spain, were collected and analysed. Results showed higher levels of HPVs in samples from Catalonia and a prevalence of phthalate esters and benzenesulfonamides over the other target compounds in samples from both locations. Multivariate analysis showed spatial differences between the mean concentration profiles of HPVs for the samples from Catalonia and the Canary Islands. Exposures were higher for the samples from Catalonia, although the intake of HPVs via seafood was not of any real concern in either of the locations.

Extraction of selected benzothiazoles, benzotriazoles and benzenesulfonamides from environmental water samples using a home-made sol-gel silica-based mixed-mode zwitterionic sorbent modified with graphene.

A novel sol-gel silica-based mixed-mode zwitterionic sorbent modified with graphene microparticles was synthesized. Thanks to the inclusion of multiple functional groups and graphene microparticles to exert a wide range of intermolecular/interionic interactions including dipole-dipole interactions, ion-exchange interactions and π-π interactions, the sorbent showed high retention in the solid-phase extraction (SPE) of benzothiazoles, benzotriazoles and benzenesulfonamides. The SPE protocol was optimized in terms of pH, sample loading volume and elution conditions using liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS). The method based on SPE followed by LC-HRMS was validated. Apparent recoveries at two levels of concentration were in the range from 48 to 85% (in most cases) in matrices such as influent wastewater, matrix effect was lower than ±30% in most cases, method detection and quantification limits being lower than 20 ng/L and repeatability and reproducibility between days were lower than 18% (n = 4). River, effluent and influent wastewaters samples were analyzed, obtaining concentrations ranging from 3 to 175 ng/L in river samples, from 12 to 499 ng/L in effluent samples and from 15 to 632 ng/L in influent samples, when the compounds were above the method quantification limits.

Determination of benzothiazoles, benzotriazoles and benzenesulfonamides in seafood using quick, easy, cheap, effective, rugged and safe extraction followed by gas chromatography - tandem mass spectrometry: Method development and risk assessment.

The common use of benzothiazoles, benzotriazoles and benzenesulfonamides has led to widespread ubiquity in several environmental matrices. Their occurrence in edible fish could represent an additional exposure route for the population. The present study aims to develop a method for the simultaneous determination of these three compound families in seafood samples. Based on QuEChERS extraction, different salt combinations and clean-up strategies have been evaluated to achieve the highest recoveries while reducing the matrix effect in low and high lipidic content species. The best results were obtained with the original method salts and the lipid-selective push-through clean-up, which combined with gas chromatography-tandem mass spectrometry led to recoveries between 50 and 112% with negligible matrix effects and method detection limits between 0.15-9.50 ng g-1 dw. The application of the method to commercially available samples confirmed the presence of BTs as well as BSAs, with the latter being determined in seafood for the first time. Exposure and risk assessment calculations indicated a minor risk for the population when consuming fish.

High production volume chemicals in the most consumed seafood species in Tarragona area (Spain): Occurrence, exposure, and risk assessment.

Seafood consumption has become a potential exposure route towards high production volume chemicals (HPVs) due to the pathway of these compounds reaching the aquatic environment via industrial and domestic discharges. The present study focuses on the determination of phthalate esters (PAEs), organophosphate esters (OPEs), benzothiazoles (BTs), benzotriazoles (BTRs) and benzenesulfonamides (BSAs) in the ten most consumed fish species in Catalonia. A total of 120 commercially available seafood specimens were purchased throughout February 2019-February 2020 in three different stores (supermarket, local market, and local fishmonger) of the city of Tarragona, Spain, to cover the most typical places where seafood can be obtained. ΣOPEs, ΣBTs, ΣBSAs and ΣPAEs concentrations ranged between 5.99 and 139.45 ng g-1 w.w., 8.41-54.08 ng g-1 w.w., 8.38-304.47 ng g-1 w.w and 2.86-323.80 ng g-1 w.w., respectively. BTRs were not detected in any of the samples. PAEs and BSAs had similar contributions which combined represented nearly the 70% of detected compounds and sardine resulted as the species with the higher HPVs mean concentration. No considerable threat was posed due to the individual intake of these compounds via seafood consumption.

Development of a Liquid Chromatography-Tandem Mass Spectrometry Method for the Simultaneous Determination of 40 Drugs of Abuse in Human Urine: Application to Real Cases.

Drugs of abuse are constantly evolving, while new synthetized substances are constantly emerging to avoid regulations. However, traditional drugs such as cocaine and amphetamine are still two of the most consumed drugs in the world. It is important, therefore, to provide suitable multiresidue methods for determining a wide range of drugs for use in toxicological and forensic analyses. The aim of this study is to develop a method for determining several families of drugs of abuse, including classic drugs, new psychoactive substances and some of their metabolites, in urine by liquid chromatography-tandem mass spectrometry. Urine is one of the most common biological matrices used in drug analysis because of its easy collection and a wide window of detection. In this study, we used solid-phase extraction to remove interferences and extract analytes from urine. Four different mixed-mode cation-exchange commercial sorbents were evaluated. The best results, in terms of apparent recoveries, were achieved with one of the strong cationic sorbents, ExtraBond SCX. The method achieved detection limits from 0.003 to 0.500 ng/mL and quantification limits from 0.050 to 1.500 ng/mL, which are suitable for determining these compounds at the usual levels found in the urine of drug users. The applicability of this method was demonstrated by analyzing real urine specimens from women following a detoxification program. Our results showed that the drug most consumed was cocaine, since it was detected in most urine specimens together with its main metabolite, benzoylecgonine. The polyconsumption of drugs from different families was also observed in some urine samples analyzed.

Determination of Organophosphate Ester Metabolites in Seafood Species by QuEChERS-SPE Followed by LC-HRMS.

Organophosphate triesters are compounds widely used in industries and are ubiquitous in the environment, where they can be transformed into organophosphate diesters. Some organophosphate diesters are also used by industry. Several studies suggest organophosphate diesters can have toxic effects for reproduction, and hazardous and mutagenic properties. Due to the impact these compounds can have on marine biota and human beings through the consumption of fish and shellfish, it is necessary to study their presence in widely consumed seafood species. We therefore developed an analytical method for determining six of the most common organophosphate diesters in seafood. The procedure is based on the Quick, Easy, Cheap, Effective, Rugged and Safe extraction method and a solid phase extraction clean-up, followed by liquid chromatography coupled to high-resolution mass spectrometry. The method was optimised and validated for seafood with different lipid content, providing satisfactory relative recoveries (from 89 to 138%) and limits of detection (1.0-50 ng g-1 dry weight), as well as repeatability values (RSD% (n = 5, 100 ng g-1 (dry weight)) lower than 15%. Eight seafood species were analysed using this method and two organophosphate diesters were detected and quantified in all the samples, demonstrating the suitability of the method.

Occurrence of organic contaminants bonded to the particulate matter from outdoor air influenced by industrial activities.

This paper discusses the occurrence of organic contaminants bonded to particulate matter (PM) in ambient air. We describe the presence and concentration levels of contaminants mainly reported in atmospheres close to factories or at locations influenced by them, and the relationship between factory emissions and the type of organic contaminants found in PM samples from the surrounding air. Many organic contaminants have been found in these types of samples, including polycyclic aromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polychlorinated biphenyls (PCBs). Their sources, fates and distributions in the ambient atmosphere are therefore well known. However, in addition to these most studied compounds, others are also of concern nowadays due to their detection and toxic effects on the environment. The continuous updating of regulations on these contaminants and the appearance of new air pollutants make it important to be aware of their occurrence. This will help to either establish new guidelines for the newer contaminants or reassess existing limitations for known ones. Moreover, if we know their occurrence, we can analyse their sources, destinations and distributions in the outdoor air.

Development of sol-gel silica-based mixed-mode zwitterionic sorbents for determining drugs in environmental water samples.

Four novel mixed-mode zwitterionic silica-based functionalized with strong moieties sorbents were synthesized and evaluated through solid-phase extraction (SPE) to determine acidic and basic drugs in environmental water samples. All sorbents had the same functionalization: quaternary amine and sulfonic groups and C18 chains so that hydrophobic and strong cationic exchange (SCX) and strong anionic exchange (SAX) interactions could be exploited, in addition, two of them had carbon microparticles embedded. All sorbents retained both acidic and basic compounds in the preliminary assays but only the basic compounds were retained selectively through ionic exchange interactions when a clean-up step was introduced. The SPE method was therefore optimized to promote the selective retention of the basic compounds, initially with the two best-performing sorbents. After optimization of the SPE protocol, these sorbents were evaluated for the analysis of environmental water samples using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The method with the best-performing sorbent was then validated with 100 mL of river samples and 50 mL of effluent wastewater samples in terms of apparent recoveries (%Rapp) spiking samples at 50 ng/L (river) and 200 ng/L (river and effluent), matrix effect, linear range, method quantification and detection limits, repeatability, and reproducibility. It should be highlighted that %Rapp ranged from 40 to 85% and matrix effects ranged from -17 to -4% for spiked river samples. When the method was applied to river and effluent wastewater samples, most compounds were found in the range from 24 to 1233 ng/L with detection limits from 1 to 5 ng/L.

Evaluation of air quality in indoor and outdoor environments: Impact of anti-COVID-19 measures.

This study monitors the presence of 88 volatile organic compounds (VOCs) and semi-volatile organic compounds (semi-VOCs) at the gas phase of seven indoor settings in a school in the city of Tarragona, Spain, and five outdoor locations around the city. The VOCs and semi-VOCs monitored were solvents (∑Solvents), aldehydes (∑Aldehydes), emerging organic compounds (∑EOCs), and other VOCs and semi-VOCs (∑Others). Passive sampling campaigns were performed using Carbopack X tubes followed by thermal desorption coupled to gas chromatography with mass spectrometry (TD-GC-MS). Overall, 70 of the target compounds included in the method were determined in the indoor air samples analysed, and 42 VOCs and semi-VOCs in the outdoor air samples. Our results showed that solvents were ubiquitous throughout the school at concentrations ranging from 272 µg m-3 to 423 µg m-3 and representing 68%-83% of total target compounds (∑Total). The values of ∑Total in 2021 were three times as high as those observed at the same indoor settings in 2019, with solvents experiencing the greatest increase. A plausible explanation for these observations is the implementation of anti-COVID-19 measures in the indoor settings, such as the intensification of cleaning activities and the use of hydroalcoholic gels as personal hygiene. The ∑Total values observed in the indoor settings evaluated were twenty times higher than those found outdoors. ∑Solvents were the most representative compounds found indoors (74% of the ∑Total). The concentrations of VOCs and semi-VOCs observed in the outdoors were strictly related to combustion processes from automobile traffic and industrial activities, with ∑Others contributing 58%, ∑Solvents 31%, and ∑Aldehydes 11% of the ∑Total. EOCs, on the other hand, were not detected in any outdoor sample.

Multiresidue analytical method for high production volume chemicals in dust samples, occurrence and human exposure assessment.

A multiresidue analytical method based on pressurised liquid extraction and gas-chromatography mass spectrometry was developed to determine 22 compounds belonging to different chemical families in indoor dust.: Seven organophosphate esters, six phthalate esters, three benzotriazoles, five benzothiazoles and four benzenesulfonamides were included in the present study, all of them belonging to the category of high production volume chemicals (HPVCs). Apparent recoveries ranged between 45% and 123% and method quantification limits ranged from 0.03 µg/g to 3.8 µg/g. The occurrence of the selected HPVCs was evaluated in indoor dust from different locations in the Tarragona (Catalonia, Spain) region. Two benzenesulfonamides, ortho-toluenesulfonamide and para-toluenesulfonamide, were detected in dust samples for the first time. Phthalate esters and organophosphate esters were the most abundant compounds found, and di-(2-ethylhexyl) phthalate (DEHP) was determined at the highest concentrations. With the data obtained, human exposure was assessed by calculating the estimated daily intakes (EDI) via ingestion and dermal contact. Non-carcinogenic and carcinogenic risk assessments found no risks in any of the scenarios tested, which included two age classes (children and adults) and two possible exposure scenarios (median and worst-case scenario), except for the evaluation of carcinogen risk due to ingestion of DEHP in the worst-case scenario.

Weak anion-exchange mixed-mode materials to selectively extract acidic compounds by stir bar sorptive extraction from environmental waters.

In this study, the first example of a polytetrafluoroethylene (PTFE)-based magnet coated with weak anion exchange (WAX) monolith as novel support for stir bar sorptive extraction (SBSE) is presented. Firstly, the PTFE magnets were properly modified and vinylized in order to immobilize polymer monoliths onto its surface. Then, a glycidyl methacrylate monolith was prepared and modified with ethylenediamine (EDA) to create weak anion exchanger via ring opening reaction of epoxy groups. The prepared covalently immobilized EDA-modified monoliths onto PTFE magnet exhibited good stability and reusability. Application of resulting material as stir bar for SBSE was investigated for a series of acidic compounds that includes acesulfame, saccharin, diclofenac or ibuprofen, among others as target compounds. Firstly, the SBSE conditions were optimized to promote the WAX interactions with the target compounds achieving recoveries from 37 to 75% and enable the selective extraction of these compounds as it provided values of% matrix effect from 17 to -13% when they were determined by SBSE followed by liquid chromatography - tandem mass spectrometry. The analytical methodology, was then validated and applied for the determination of the target solutes in environmental water samples, which were found at concentration up to 2500 ng L-1 in river waters.

Hypercrosslinked polymer microspheres decorated with anion- and cation-exchange groups for the simultaneous solid-phase extraction of acidic and basic analytes from environmental waters.

Mixed-mode ion-exchange sorbents were introduced to improve the selectivity and retention of solid-phase extraction (SPE) sorbents. Mixed-mode ion-exchange sorbents integrate reversed-phase chemistry with ion-exchange groups to promote favourable interactions with ionic species. Nevertheless, a need to extract analytes with acidic and basic properties simultaneously within the same SPE cartridge led to the introduction of novel amphoteric/zwitterionic sorbents, which incorporate cation- and anion-exchange moieties within the same functional group attached to the polymeric network. In the present study, the development, preparation and SPE evaluation of two novel hypercrosslinked zwitterionic polymeric sorbents, functionalised with either strong anion-exchange (SAX) and weak cation-exchange (WCX) or weak anion-exchange (WAX) and strong cation-exchange (SCX) groups (namely HXLPP-SAX/WCX and the HXLPP-WAX/SCX), is presented for the simultaneous retention of acidic and basic compounds. The sorbents were prepared by a precipitation polymerisation route which yielded poly(divinylbenzene-co-vinylbenzylchloride) as a precursor polymer; subsequently, the precursor polymer was hypercrosslinked, to increase the specific surface areas and capacities of the sorbents, and then functionalised to impart the zwitterionic character. The HXLPP-SAX/WCX sorbent was decorated with quaternised sarcosine groups and the HXLPP-WAX/SCX sorbent was decorated with taurine moieties. The SPE parameters were optimised to exploit the ionic interactions between compounds and the functional groups. The optimal conditions involve a washing step to remove the compounds retained by hydrophobic interactions, thus increasing the selectivity. The optimised SPE protocol used the quaternised sarcosine-based sorbent followed by liquid chromatography and tandem mass spectrometry, and was applied to determine compounds with acidic and basic properties from environmental samples, such as river water and effluent wastewater samples, with excellent selectivity and matrix effect values below -30% and apparent recovery results ranging from 52% to 105% for most of the compounds. The analytical method was validated for environmental water samples and used in the analysis of samples in which some of the target compounds were found at ng L-1 concentration levels.

Comparison of different chiral selectors for the enantiomeric determination of amphetamine-type substances in human urine by solid-phase extraction followed by capillary electrophoresis-tandem mass spectrometry.

The present study develops a method for the enantioseparation of a group of amphetamines and their metabolites in urine by CE coupled to MS/MS (CE-MS/MS). Amphetamines present a chiral center and thus two enantiomers, which is important from a toxicological point of view because they may have different pharmacokinetic and pharmacological properties. It is therefore essential to find suitable methods to distinguish both enantiomers. Today the use of CE is becoming more important in this field since, with the simple addition of a chiral selector to the background electrolyte, the enantioseparation can easily be achieved. However, when CE is coupled to MS, the use of volatile chiral selectors and compatible background electrolytes or other strategies such as the countercurrent migration approach are required to avoid contamination of the ion source from nonvolatile species. In the present study, we use the latter strategy to evaluate six different chiral selectors using CE-MS/MS. As a sample pre-treatment, two cationic-exchange sorbents-Oasis WCX and Oasis MCX-are compared for the urine pre-treatment. Using this method, it was possible to achieve the complete chiral separation of the amphetamines under study with detection limits ranging between 0.8 and 1.5 ng/mL and method quantification limits between 2.0 and 8.0 ng/mL. Matrix-matched calibration curves up to 150 ng/mL were used to cover the usual concentration ranges at which amphetamines have generally been found in toxicological and forensic analyses.

Presence of emerging organic contaminants and solvents in schools using passive sampling.

In this study, we report on the applicability of passive sampling with Carbopack X adsorbent tubes followed by thermal desorption gas-chromatography-mass spectrometry (TD-GC-MS) to monitor the concentrations of emerging organic contaminants (EOCs) and solvents in ten indoor environments in a conventional and a vocational training school. However, if passive sampling is to be used as a reliable sampling technique, a specific diffusive uptake rate is required for each target compound. Accordingly, the aim of the present study was twofold. The first was to determine the experimental diffusive uptake rates of the target EOCs and solvents in one of the sampling sites of the vocational training school using Carbopack X adsorbent tubes and active sampling as the reference technique. The results showed experimental diffusive uptake rates between 0.46 mL min-1 and 0.94 mL min-1 with RSD % below 5% for the 28 target compounds. The second was to apply the uptake rates obtained experimentally to determine EOCs and solvents in schools. The monitoring results showed that solvents were ubiquitous throughout the conventional school with a concentrations range between 51.93 µg m-3 and 164.6 µg m-3, while EOCs were detected to a lesser extent. Moreover, the concentrations of EOCs in the vocational training school were much higher than those in the conventional school with concentrations of up to 562.9 µg m-3 for solvents and 344.3 µg m-3 for acrylate polymer monomers. After actively sampling for seven days in each school, we concluded that the concentrations of EOCs and solvents found are mostly linked to cleaning products (conventional school) and the activities carried out in the classroom (vocational training school).

Presence, behaviour and removal of selected organic micropollutants through drinking water treatment.

This paper investigates the occurrence and removal of 60 organic micropollutants (OMPs) including pharmaceuticals, personal care products, pesticides and per- and polyfluoroalkyl substances in a drinking water treatment plant (DWTP) treating raw water from the Ebro River (NE Spain). The behaviour of the OMPs was evaluated in each treatment: pre-ozonation, flocculation-coagulation-decantation-sand filtration, post-ozonation and granular activated carbon filtration. Thirty-one of the sixty OMPs studied were detected in source water with individual median concentrations below 10 ng L-1 for all the compounds except for caffeine (64.1 ng L-1). The highest concentration peaks in the source water were found for caffeine (124.5 ng L-1), terbuthylazine (52.0 ng L-1), imidacloprid (30.2 ng L-1) and paracetamol (25.6 ng L-1). Of the 31 compounds detected in the source water, 17 were also detected in the finished drinking water. Of these 17 compounds, 10 were PFASs, which indicated that this group of compounds had not been effectively removed throughout the drinking water treatments. The overall removal efficiencies of OMPs in the DWTP ranged from -50.9% to 100%. The most efficient removal technologies were ozonation and granular activated carbon.