► Fifty-three emerging pollutants measured in sewage, surface and drinking water. ► Nineteen compounds detected in sewage at median values higher than 0.1μgL. ► Eleven of them not properly eliminated ...and still higher than 0.1μgL−1 in effluent. ► Pharmaceuticals, UV filters and organoP flame retardants prevail in surface water. ► BP-4, TnBP, TCEP and several organoP diesters found in drinking water at 10–100ngL−1.
A monitoring programme was carried out on wastewater, surface and drinking water on the NW area of Spain during the four seasons of a year period (November 2007–September 2008). This study covered a series of emerging pollutants of different classes, including pharmaceuticals, neutral and acidic organophosphorus flame retardant/plasticizers (OPs), triclosan, phenoxy-herbicides, insect repellents and UV filters. From the total set of 53 compounds, 19 were found in raw wastewater with median concentrations higher than 0.1μgL−1. Among them, salicylic acid, ibuprofen and the UV filter benzophenone-4 (BP-4) were the most concentrated, exceeding the 1μgL−1 median value. Subsequently, 11 of these contaminants are not efficiently enough removed in the small WWTPs tested and their median concentrations in effluents still surpassed the 0.1μgL−1, so that they can spread through surface water. These chemicals are the pharmaceuticals naproxen, diclofenac and atenolol; the OPs tri(2-chloroethyl) phosphate (TCEP), tri(chloropropyl) phosphate (TCPP), tri-n-butyl phosphate (TnBP), diphenyl phosphate (DPhP) and diethylhexyl phosphate (DEHP); and the sulphonate UV filters BP-4 and 2-phenylbenzimidazole-5-sulphonic acid (PBSA). These OPs were then the dominant emerging pollutants occurring in surface and drinking water, where they are detected in the 20–200ngL−1 range. Pharmaceuticals and UV filters are typically below the 10ngL−1 level. Finally, herbicides were only detected in the last sampling campaign under the 100ngL−1 drinking water European Union limit.
Infrared spectrometry (IR) became a workhorse to characterize microplastics (MPs) worldwide. However, reports on the experimental conditions to measure them decreased alarmingly. As complete, ...relevant information on the instrumental setup determining IR spectra is crucial for scientific reproducibility, ca. 50% of the papers that reported FTIR to measure MPs were evaluated and it was found that most studies cannot be replicated due to missing experimental details. To ameliorate this, the most critical parameters influencing IR spectra are depicted, their impact when matching a spectrum against databases exemplified, and, following efforts from other scientific fields, a minimum information for publication of IR-related data on MPs characterization (MIPIR-MP) is proposed, along with a brief, simple paragraph to resume the most critical information to be reported. This can be used to improve the worrying figures that point out to a reproducibility crisis in the field, as disclosed by the survey.
•Studies on microplastics lack information on IR measurement setup parameters•Around 25% of published papers do not offer useful instrumental information•A lack of understanding of basic IR parameters might affect polymer identifications•The quality of reported data on microplastics is compromised•A paragraph is proposed to minimize the lack of IR instrumental information
This paper describes the development and validation of a method for the simultaneous determination of 53 multi-class emerging organic pollutants in water samples using solid-phase extraction (SPE) ...followed by liquid chromatography–tandem mass spectrometry (LC–MS/MS), using electrospray ionisation (ESI) in both positive and negative modes. Target compounds include acidic herbicides, UV filters, insect repellents, organophosphorous flame retardants, a bactericide, pharmaceuticals and metabolites. A single SPE consisting on the loading of 200–500
mL of sample adjusted to pH 7 on Oasis HLB 200
mg cartridges and elution with methanol, permitted obtaining good recoveries: higher than 60% for tap, surface and wastewater in most cases. The 7 isotopically labelled internal standards effectively compensated losses during sample preparation and matrix effects at LC–MS/MS determination. The precision of the method, calculated as relative standard deviation (RSD) was below 15% for all compounds and all tested matrices. Detection limits (LODs) based on the confirmation, less intense, MRM (multiple reaction monitoring) transition and considering blanks varied between 0.3 and 30
ng
L
−1. Finally, the developed method was applied to the determination of target analytes in various samples, including tap, surface and waste water. Among the tested emerging pollutants, 31 were found in wastewater in concentrations reaching up to 10
μg
L
−1 in the case of ibuprofen. Also, 13 species were detected in tap water with concentrations up to 0.13
μg
L
−1 for tri(chloropropyl) phosphate (TCPP).
The degradation of seven acidic drugs and two metabolites during chlorination was investigated by liquid chromatography–mass spectrometry (LC–MS). A triple-quadrupole (QqQ) system was used to follow ...the time course of the pharmaceuticals and by-products, while a quadrupole time-of-flight (Q-TOF) system was also used for the identification of the by-products. Under strong chlorination conditions (10mg/L Cl2, 24h), only four of the target compounds were significantly degraded: salicylic acid, naproxen, diclofenac and indomethacine. The degradation kinetics of these four compounds were investigated at different concentrations of chlorine, bromide and pH by means of a Box–Behnken experimental design. Depending on these factors, measured pseudo-first order half-lives were in the ranges: 23–573h for salicylic acid, 13–446min for naproxen, 5–328min for diclofenac and 0.4–13.4min for indomethacine. Also, it was observed that chlorine concentration was the overall most significant factor, followed by the bromide concentration (except for indomethacine), resulting in increased degradation kinetics as they are increased. The degradation path of salicylic acid, naproxen and diclofenac consisted of aromatic substitution of one or two hydrogens by chlorine and/or bromide. Moreover, for diclofenac, two other by-products corresponding to a decarboxylation/hydroxylation pathway from the monohalogenated products were also identified. On the other hand, indomethacine degradation did not lead to halogenation products but to oxidation ones. The investigation of these by-products in real samples by LC–MS/MS (QqQ) showed that the halogenated derivates of salicylic acid occurred in all the drinking water and wastewater samples analysed.
Microplastics (MPs) affect plankton (a basis of the trophic chain) and planktivorous fish can ingest them through food confusion or by trophic transmission. Consensus to determine MPs in plankton is ...lacking and, so, three digestion treatments were evaluated: Alkaline (potassium hydroxide) and enzymatic (protease plus lipase) digestions, both combined with a hydrogen peroxide stage; and an oxidative method using a surfactant (sodium dodecyl sulfate) plus hydrogen peroxide. The alkaline method using potassium hydroxide was found to damage polystyrene. MPs were identified with a stereomicroscope and characterized by reflectance infrared microscopy in semi-automatic mode (using dedicated multi-well aluminium plates). Analytical recoveries for polypropylene, polystyrene, polyethylene, polyamide, polyvinyl chloride and polyethylene terephthalate were higher than 75%, 82% and 83% for the alkaline, enzymatic and oxidative treatments, respectively. The enzymatic method was successfully validated in a European interlaboratory exercise and the oxidative method was demonstrated to be a reliable, fast and cheaper alternative.
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•A cost-efficient, plastic-safe protocol was developed to digest plankton samples.•Combining alkaline and oxidative treatments can be harmful in polystyrene MPs.•Multi-well plates reduced the measurement time in a FTIR microscope.•The enzymatic method was validated in a European interlaboratory exercise.•The oxidative method is a reliable (and cheaper) alternative to the enzymatic one.
Currently, gas chromatography is the most common analytical technique for natural gas (NG) analysis as it offers very precise results, with very low limits of detection and quantification. However, ...it has several drawbacks, such as low turnaround times and high cost per analysis, as well as difficulties for on-line implementation. With NG applications rising, mostly thanks to its reduced gaseous emissions in comparison with other fossil fuels, the necessity for more versatile, fast, and economic analytical methods has augmented. This work summarizes the latest advances to determine the composition and physico-chemical properties of regasified liquid natural gas, focusing on infrared spectroscopy-based techniques, as well as on data processing (chemometric techniques), necessary to obtain adequate predictions of NG properties.
In-vivo and
in-vitro gastrointestinal (GI) extractions, also known as oral bioaccessibility and bioavailability, are important approaches to assess chemical risk to humans. We give an overview of
...in-vivo and
in-vitro bioaccessibility and bioavailability assays for testing arsenic, selenium and mercury (As, Se and Hg) species from food samples. We critically evaluate the parameters affecting
in-vivo and
in-vitro processes. In addition, we consider the effect of cooking food on bioaccessibility and bioavailability, and stability and transformation, of species during
in-vivo or
in-vitro processes. The bioaccessibility and bioavailability of As, Se and Hg species are affected by the sample matrix, cooking food and the experimental conditions applied (gastric and intestinal pH, incubation temperature and residence time). Regarding species degradation and transformation during
in-vitro procedures, good stability has been observed for most As species, except for certain arsenosugars. Important transformations during
in-vitro processes have been reported for Se species e.g., conversion of γ-glu-Se-MeSeCys to Se-MeSeCys, and organic Se species (MeSeCys, SeCys2 and SeMet) degradation to inorganic Se. Finally, we summarize speciation and detection conditions for As, Se and Hg speciation, and quality control to assure reliable measurements.
The hydrophobicity of persistent organic pollutants (POPs) makes them adsorb on microplastics in the marine environment, affecting their distribution, persistence, or their transfer to the trophic ...chain. Fragrances and non-polar pesticides can be adsorbed by microplastics in the marine environment because of their physico-chemical characteristics.
In this work, the adsorption of two pesticides (α-endosulfan and chlorpyrifos) and 6 musk fragrances (musk xylene, musk ketone, musk moskene, galaxolide, tonalide, and celestolide) on polyamide (PA6) (a petroleum based polymer) and on polyhydroxybutyrate (PHB) (biopolymer) in seawater was studied, considering also the effect of water temperature and plastic weathering.
Results show higher adsorption of the selected pollutants for PHB than PA, being PA more affected by the water temperature and the plastic weathering. The highest percentage of adsorption was achieved in most cases at 24 h. In addition, this process was irreversible, as it showed the leaching assays. Besides, this work revealed that plastics mitigate the degradation of α-endosulfan in aquatic media (hydrolysis), showing that plastics can act as inhibitors of degradation of POPs, increasing its persistence in the environment.
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•Lower sorption of environmental pollutants to PA than to PHB.•POPs sorption capacity of PA more affected by water temperature than PHB•Adsorption irreversible: capacity of PA and PHB to accumulate these contaminants.•Microplastics can inhibit the degradation of sorbed POPs increasing their lifetime.•Quality controls and verification of analytical processes provide reliable results.
Polycyclic aromatic hydrocarbons (PAHs) inhalation bioaccessibility was assessed in 65 atmospheric particulate matter samples (PM10) collected at an Atlantic coastal European urban site. The proposed ...method consists on a physiologically based extraction (PBET) by using Gamble’s solution followed by a vortex assisted liquid-liquid micro-extraction (VALLME) and quantification by high performance liquid chromatography with fluorescence detection (HPLC-FLD). The use of a micro-extraction technique combined with FLD detection, provides a simple, fast, sensitive, accurate and low-cost methodology to PAHs quantification in bioaccessible fractions. Accuracy of the bioaccessibility study was assessed by means of a mass balance approaches using a PM10 filter and a certified reference material (ERM-CZ100). High-moderate inhalation bioaccessibilities were found for phenanthrene (Phe), fluoranthene (Ft) and pyrene (Pyr) (average ratios in the 52–65% range); while dibenz (a,h)anthracene (DBahA), indeno (1,2,3-cd)pyrene (IP) and benzo (g,h,i)perylene (BghiP) were observed to be less bioaccessibles (average ratios in the 11–14% range). Relationship between PM10 composition (major ions, trace metals, equivalent black carbon (eBC) and UV-absorbing particulate matter (UVPM)) and PAHs bioaccessibility ratios was also assessed. Principal Component Analysis (PCA) showed that PAHs bioaccessibility percentage is dependent on anthropogenic (eBC, UVPM and Sb concentrations) and marine sources of PM10. Predicted PAHs bioaccessibilities after applying a multiple linear regression model based on marine and anthropogenic source of PM10 could also be established. Health risk assessment of target PM10-associated PAHs via inhalation was assessed considering bioaccessibility concentrations by using hazard index (HI) and BaP equivalent concentration (BaPeq) approaches, suggesting no carcinogenic risk in the area during the sampling campaign.
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•Inhalation bioaccessibility of PM10-associated PAHs was estimated by Gamble’s solution.•PAHs bioaccessibilities decreased when the number of rings were increased.•Correlation between PM10 properties and PAHs bioaccessibility percentages were observed.•Inhalation health risk assessment posed by PM10-associated PAHs was estimated using bioaccessible fraction.
A novel analytical method based on solid-phase extraction (SPE) and liquid chromatography−electrospray ionization-tandem mass spectrometry (LC−ESI-MS/MS) for the determination of UV sunscreen agents ...in the water environment is presented. After a thorough investigation of SPE and LC−MS/MS conditions, it permits the enrichment and determination of nine of these compounds in a single methodology, including three very polar sulfonates (e.g., 2-phenylbenzimidazole-5-sulfonic acid, PBSA) and six other less polar compounds (e.g., benzophenone-3, BP-3; octocrylene, OC,...). Other important matters of concern in the determination of UV filters at trace levels in water, i.e., adsorption on glassware and blank contamination problems, have also been discussed and minimized. This methodology affords detection limits between 7 and 46 ng L-1 and SPE recoveries in the range 63−102% from different real water matrixes, except for butylmethoxydibenzoylmethane (BM-DBM), which was not determinable in wastewater samples due to adsorption problems. The application of the method allowed reporting the levels of benzophenone-4 (BP-4) in environmental water samples for the first time, where it was identified as one of the most important in concentration among the UV filters studied, particularly in wastewater (237−1481 ng L-1).
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