| 1. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 2. |
- Dewapriya, Pradeep, et al.
(författare)
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Novel Per- and Polyfluoroalkyl Substances Discovered in Cattle Exposed to AFFF-Impacted Groundwater
- 2023
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Ingår i: Environmental Science and Technology. - 0013-936X .- 1520-5851. ; 57:36, s. 13635-13645
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Tidskriftsartikel (refereegranskat)abstract
- The leaching of per- and polyfluoroalkyl substances (PFASs) from Australian firefighting training grounds has resulted in extensive contamination of groundwater and nearby farmlands. Humans, farm animals, and wildlife in these areas may have been exposed to complex mixtures of PFASs from aqueous film-forming foams (AFFFs). This study aimed to identify PFAS classes in pooled whole blood (n = 4) and serum (n = 4) from cattle exposed to AFFF-impacted groundwater and potentially discover new PFASs in blood. Thirty PFASs were identified at various levels of confidence (levels 1a–5a), including three novel compounds: (i) perfluorohexanesulfonamido 2-hydroxypropanoic acid (FHxSA-HOPrA), (ii) methyl((perfluorohexyl)sulfonyl)sulfuramidous acid, and (iii) methyl((perfluorooctyl)sulfonyl)sulfuramidous acid, belonging to two different classes. Biotransformation intermediate, perfluorohexanesulfonamido propanoic acid (FHxSA-PrA), hitherto unreported in biological samples, was detected in both whole blood and serum. Furthermore, perfluoroalkyl sulfonamides, including perfluoropropane sulfonamide (FPrSA), perfluorobutane sulfonamide (FBSA), and perfluorohexane sulfonamide (FHxSA) were predominantly detected in whole blood, suggesting that these accumulate in the cell fraction of blood. The suspect screening revealed several fluoroalkyl chain-substituted PFAS. The results suggest that targeting only the major PFASs in the plasma or serum of AFFF-exposed mammals likely underestimates the toxicological risks associated with exposure. Future studies of AFFF-exposed populations should include whole-blood analysis with high-resolution mass spectrometry to understand the true extent of PFAS exposure.
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| 3. |
- McLachlan, Michael S., et al.
(författare)
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Removal of 293 organic compounds in 15 WWTPs studied with non-targeted suspect screening
- 2022
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Ingår i: Environmental Science. - : Royal Society of Chemistry (RSC). - 2053-1400 .- 2053-1419. ; 8:7, s. 1423-1433
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Tidskriftsartikel (refereegranskat)abstract
- Understanding how contaminant breakthrough in wastewater treatment plants is influenced by chemical structure and treatment technology is important for protecting the aquatic environment. In order to assess this question, consistent contaminant breakthrough measurements are required for a large number of chemicals. Using direct injection UHPLC-Orbitrap-MS/MS with data-dependent non-target data acquisition followed by suspect screening against a library of >7000 compounds with exact mass and MS2 spectra, we quantified the removal of 293 chemicals in 15 WWTPs with widely varying treatment technology. Principle component analysis showed a clear and consistent influence of treatment technology on contaminant breakthrough. Log breakthrough was significantly correlated with log TSS and log BOD in treated effluent for 71% and 68% of the chemicals, respectively. Chemicals were identified which could be used as indicators of the standard of wastewater treatment. Furthermore, chemicals were identified that could be used to predict the breakthrough of groups of other chemicals. A high degree of correlation was found for the breakthrough of different groups of chemicals, which suggests that the data could be used to develop models describing how chemical structure influences breakthrough or removal efficiency. Non-targeted suspect screening is a useful method for generating consistent WWTP breakthrough data for large numbers of chemicals.
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| 4. |
- Mohammed Taha, Hiba, et al.
(författare)
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The NORMAN Suspect List Exchange (NORMAN-SLE) : facilitating European and worldwide collaboration on suspect screening in high resolution mass spectrometry
- 2022
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Ingår i: Environmental Sciences Europe. - : Springer. - 2190-4707 .- 2190-4715. ; 34:1
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Tidskriftsartikel (refereegranskat)abstract
- Background: The NORMAN Association (https://www.norman-network.com/) initiated the NORMAN Suspect List Exchange (NORMAN-SLE; https://www.norman-network.com/nds/SLE/) in 2015, following the NORMAN collaborative trial on non-target screening of environmental water samples by mass spectrometry. Since then, this exchange of information on chemicals that are expected to occur in the environment, along with the accompanying expert knowledge and references, has become a valuable knowledge base for “suspect screening” lists. The NORMAN-SLE now serves as a FAIR (Findable, Accessible, Interoperable, Reusable) chemical information resource worldwide.Results: The NORMAN-SLE contains 99 separate suspect list collections (as of May 2022) from over 70 contributors around the world, totalling over 100,000 unique substances. The substance classes include per- and polyfluoroalkyl substances (PFAS), pharmaceuticals, pesticides, natural toxins, high production volume substances covered under the European REACH regulation (EC: 1272/2008), priority contaminants of emerging concern (CECs) and regulatory lists from NORMAN partners. Several lists focus on transformation products (TPs) and complex features detected in the environment with various levels of provenance and structural information. Each list is available for separate download. The merged, curated collection is also available as the NORMAN Substance Database (NORMAN SusDat). Both the NORMAN-SLE and NORMAN SusDat are integrated within the NORMAN Database System (NDS). The individual NORMAN-SLE lists receive digital object identifiers (DOIs) and traceable versioning via a Zenodo community (https://zenodo.org/communities/norman-sle), with a total of > 40,000 unique views, > 50,000 unique downloads and 40 citations (May 2022). NORMAN-SLE content is progressively integrated into large open chemical databases such as PubChem (https://pubchem.ncbi.nlm.nih.gov/) and the US EPA’s CompTox Chemicals Dashboard (https://comptox.epa.gov/dashboard/), enabling further access to these lists, along with the additional functionality and calculated properties these resources offer. PubChem has also integrated significant annotation content from the NORMAN-SLE, including a classification browser (https://pubchem.ncbi.nlm.nih.gov/classification/#hid=101).Conclusions: The NORMAN-SLE offers a specialized service for hosting suspect screening lists of relevance for the environmental community in an open, FAIR manner that allows integration with other major chemical resources. These efforts foster the exchange of information between scientists and regulators, supporting the paradigm shift to the “one substance, one assessment” approach. New submissions are welcome via the contacts provided on the NORMAN-SLE website (https://www.norman-network.com/nds/SLE/).
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| 5. |
- Nguyen, Hue T., et al.
(författare)
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Background release and potential point sources of per- and polyfluoroalkyl substances to municipal wastewater treatment plants across Australia
- 2022
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Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 293
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Tidskriftsartikel (refereegranskat)abstract
- Wastewater treatment plants (WWTPs) are known to be significant sources of per- and polyfluoroalkyl substances (PFAS) to the environment. In this study, PFAS were measured in the influent of 76 municipal wastewater treatment plants (WWTPs) serving approximately 53% of the Australian population. Of fourteen target PFAS, twelve analytes including six C5–C10 perfluoroalkyl carboxylic acids (PFCAs), four C4-10 perfluoroalkyl sulfonic acids (PFSAs) and two fluorotelomer sulfonates (6:2 and 8:2 FTS) were detected. Of these, PFOS, PFHxS and PFHxA had the highest median concentrations. The per capita background release of Σ12 PFAS to WWTP influent in Australia was estimated to be 8.1–24 μg/d/per person. The background release was supplemented by contributions from catchment specific point sources (i.e., industry, airports, military bases, and landfills), whereby the number of industrial sites positively correlated with the per capita mass load of Σ12 PFAS (r = 0.5–0.63, p < 0.01). The per capita mass loads were extrapolated to the entire Australian population, with estimates suggesting that approximately 1 kg/d of Σ12 PFAS reach WWTPs in Australia (300–400 kg annually), with more than half of the PFAS (∼59%) attributed to background release and the remaining (∼41%) to catchment specific point sources. These data provide insight into the release of major PFAS to wastewater at a national scale in Australia.
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| 6. |
- O'Malley, Elissa, et al.
(författare)
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The presence of selected UV filters in a freshwater recreational reservoir and fate in controlled experiments
- 2021
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Ingår i: Science of the Total Environment. - : Elsevier BV. - 0048-9697 .- 1879-1026. ; 754
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Tidskriftsartikel (refereegranskat)abstract
- UV filters present in sunscreen and other cosmetics are directly released into the environment during aquatic recreational activities. The extent to which the wide range of UV filters pose a risk to the environment remains unclear. This study investigated the occurrence and dissipation of selected organic UV filters at a recreational site (Enoggera Reservoir, Queensland, Australia) over 12 h. Furthermore, different possible degradation processes were investigated in a controlled off-site experiment with surface water exposed to natural light. Half-lives were estimated for ten UV filters. In Enoggera Reservoir, seven UV filters were detected, of which the most prevalent were octocrylene, avobenzone (BMDBM) and enzacamene (4-MBC). Summed concentrations of the seven UV filters ranged from 7330 ng L-1 at 13:00 h to 2550 ng L-1 at 21:00 h. In the degradation experiment, four UV filters showed no significant change over time. The fate of these compounds in the environment is likely to be mainly influenced by dispersion. Half-lives of the remaining UV filters were 6.6 h for amiloxate (IMC), 20 h for benzophenone 1, 23 h for octinoxate (EHMC), 30 h for 3-benzylidene camphor, 34 h for 4-MBC and 140 h for dioxybenzone (BP8). The degree of susceptibility to photodegradation and biodegradation was generally consistent within a structural class. The fate and half-lives of UV filters are variable and should be considered on a per site basis when assessing environmental risk.
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| 7. |
- Rousis, Nikolaos I., et al.
(författare)
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Socioeconomic status and public health in Australia : A wastewater-based study
- 2022
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Ingår i: Environment International. - : Elsevier BV. - 0160-4120 .- 1873-6750. ; 167
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Tidskriftsartikel (refereegranskat)abstract
- Analysis of untreated municipal wastewater is recognized as an innovative approach to assess population exposure to or consumption of various substances. Currently, there are no published wastewater-based studies investigating the relationships between catchment social, demographic, and economic characteristics with chemicals using advanced non-targeted techniques. In this study, fifteen wastewater samples covering 27% of the Australian population were collected during a population Census. The samples were analysed with a workflow employing liquid chromatography high-resolution mass spectrometry and chemometric tools for non-target analysis. Socioeconomic characteristics of catchment areas were generated using Geospatial Information Systems software. Potential correlations were explored between pseudo-mass loads of the identified compounds and socioeconomic and demographic descriptors of the wastewater catchments derived from Census data. Markers of public health (e.g., cardiac arrhythmia, cardiovascular disease, anxiety disorder and type 2 diabetes) were identified in the wastewater samples by the proposed workflow. They were positively correlated with descriptors of disadvantage in education, occupation, marital status and income, and negatively correlated with descriptors of advantage in education and occupation. In addition, markers of polypropylene glycol (PPG) and polyethylene glycol (PEG) related compounds were positively correlated with housing and occupation disadvantage. High positive correlations were found between separated and divorced people and specific drugs used to treat cardiac arrhythmia, cardiovascular disease, and depression. Our robust non-targeted methodology in combination with Census data can identify relationships between biomarkers of public health, human behaviour and lifestyle and socio-demographics of whole populations. Furthermore, it can identify specific areas and socioeconomic groups that may need more assistance than others for public health issues. This approach complements important public health information and enables large-scale national coverage with a relatively small number of samples.
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| 8. |
- van Nuijs, Alexander L. N., et al.
(författare)
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Multi-year inter-laboratory exercises for the analysis of illicit drugs and metabolites in wastewater : development of a quality control system
- 2018
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Ingår i: TrAC. Trends in analytical chemistry. - : Elsevier. - 0165-9936 .- 1879-3142. ; 103, s. 34-43
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Forskningsöversikt (refereegranskat)abstract
- Thirty-seven laboratories from 25 countries present the development of an inter-laboratory testing scheme for the analysis of seven illicit drug residues in standard solutions, tap- and wastewater. Almost 10 000 concentration values were evaluated: triplicates of up to five samples and 26 laboratories per year. The setup was substantially improved with experiences gained across the six repetitions (e.g. matrix type, sample conditions, spiking levels). From this, (pre-)analytical issues (e.g. pH adjustment, filtration) were revealed for specific analytes which resulted in formulation of best-practice protocols for inter-laboratory setup and analytical procedures. The results illustrate the effectiveness of the interlaboratory setup to assess laboratory performance in the framework of wastewater-based epidemiology. The exercise proved that measurements of laboratories were of high quality (>80% satisfactory results for six out of seven analytes) and that analytical follow-up is important to assist laboratories in improving robustness of wastewater-based epidemiology results.
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| 9. |
- Windhorst, Rogier A., et al.
(författare)
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JWST PEARLS. Prime extragalactic areas for reionization and lensing science : project overview and first results
- 2023
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Ingår i: Astronomical Journal. - : Institute of Physics (IOP). - 0004-6256 .- 1538-3881. ; 165:1
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Tidskriftsartikel (refereegranskat)abstract
- We give an overview and describe the rationale, methods, and first results from NIRCam images of the JWST “Prime Extragalactic Areas for Reionization and Lensing Science” (PEARLS) project. PEARLS uses up to eight NIRCam filters to survey several prime extragalactic survey areas: two fields at the North Ecliptic Pole (NEP); seven gravitationally lensing clusters; two high redshift protoclusters; and the iconic backlit VV 191 galaxy system to map its dust attenuation. PEARLS also includes NIRISS spectra for one of the NEP fields and NIRSpec spectra of two high-redshift quasars. The main goal of PEARLS is to study the epoch of galaxy assembly, active galactic nucleus (AGN) growth, and First Light. Five fields—the JWST NEP Time-Domain Field (TDF), IRAC Dark Field, and three lensing clusters—will be observed in up to four epochs over a year. The cadence and sensitivity of the imaging data are ideally suited to find faint variable objects such as weak AGN, high-redshift supernovae, and cluster caustic transits. Both NEP fields have sightlines through our Galaxy, providing significant numbers of very faint brown dwarfs whose proper motions can be studied. Observations from the first spoke in the NEP TDF are public. This paper presents our first PEARLS observations, their NIRCam data reduction and analysis, our first object catalogs, the 0.9–4.5 μm galaxy counts and Integrated Galaxy Light. We assess the JWST sky brightness in 13 NIRCam filters, yielding our first constraints to diffuse light at 0.9–4.5 μm. PEARLS is designed to be of lasting benefit to the community.
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