Author Correction: Transformation of organic micropollutants along hyporheic flow in bedforms of river-simulating flumes

AbstractUrban streams receive increasing loads of organic micropollutants from treated wastewaters. A comprehensive understanding of the in-stream fate of micropollutants is thus of high interest for water quality management. Bedforms induce pumping effects considerably contributing to whole stream hyporheic exchange and are hotspots of biogeochemical turnover processes. However, little is known about the transformation of micropollutants in such structures. In the present study, we set up recirculating flumes to examine the transformation of a set of micropollutants along single flowpaths in two triangular bedforms. We sampled porewater from four locations in the bedforms over 78 days and analysed the resulting concentration curves using the results of a hydrodynamic model in combination with a reactive transport model accounting for advection, dispersion, first-order removal and retardation. The four porewater sampling locations were positioned on individual flowpaths with median solute travel times ranging from 11.5 to 43.3 h as shown in a hydrodynamic model previously. Highest stability was estimated for hydrochlorothiazide on all flowpaths. Lowest detectable half-lives were estimated for sotalol (0.7 h) and sitagliptin (0.2 h) along the shortest flowpath. Also, venlafaxine, acesulfame, bezafibrate, irbesartan, valsartan, ibuprofen and naproxen displayed lower half-lives at shorter flowpaths in the first bedform. However, the behavior of many compounds in the second bedform deviated from expectations, where particularly transformation products, e.g. valsartan acid, showed high concentrations. Flowpath-specific behavior as observed for metformin or flume-specific behavior as observed for metoprolol acid, for instance, was attributed to potential small-scale or flume-scale heterogeneity of microbial community compositions, respectively. The results of the study indicate that the shallow hyporheic flow field and the small-scale heterogeneity of the microbial community are major controlling factors for the transformation of relevant micropollutants in river sediments.

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Resorcinarene Cavitand Polymers for the Remediation of Halomethanes and 1,4-Dioxane

10.26434/chemrxiv.8847839 ◽

2019 ◽

Author(s):

Luke Skala ◽

Anna Yang ◽

Max Justin Klemes ◽

Leilei Xiao ◽

William Dichtel

Keyword(s):

Drinking Water ◽

Activated Carbon ◽

High Capacity ◽

The United States ◽

Water Sources ◽

Disinfection Byproducts ◽

Porous Polymer ◽

Organic Micropollutants ◽

Executive Summary ◽

Regulatory Limits

Executive summary: Porous resorcinarene-containing polymers are used to remove halomethane disinfection byproducts and 1,4-dioxane from water. Disinfection byproducts such as trihalomethanes are some of the most common micropollutants found in drinking water. Trihalomethanes are formed upon chlorination of natural organic matter (NOM) found in many drinking water sources. Municipalities that produce drinking water from surface water sources struggle to remain below regulatory limits for CHCl3 and other trihalomethanes (80 mg L–1 in the United States). Inspired by molecular CHCl3⊂cavitand host-guest complexes, we designed a porous polymer comprised of resorcinarene receptors. These materials show higher affinity for halomethanes than a specialty activated carbon used for trihalomethane removal. The cavitand polymers show similar removal kinetics as activated carbon and have high capacity (49 mg g–1 of CHCl3). Furthermore, these materials maintain their performance in real drinking water and can be thermally regenerated under mild conditions. Cavitand polymers also outperform activated carbon in their adsorption of 1,4-dioxane, which is difficult to remove and contaminates many public water sources. These materials show promise for removing toxic organic micropollutants and further demonstrate the value of using supramolecular chemistry to design novel absorbents for water purification.

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Faculty Opinions recommendation of Cometabolic Enzymatic Transformation of Organic Micropollutants under Methanogenic Conditions.

Faculty Opinions – Post-Publication Peer Review of the Biomedical Literature ◽

10.3410/f.727308056.793571014 ◽

2020 ◽

Author(s):

Lily Young

Keyword(s):

Organic Micropollutants ◽

Enzymatic Transformation

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Multivariate micropollutants analysis in marine waters

Water Science & Technology ◽

10.2166/wst.1995.0701 ◽

1995 ◽

Vol 32 (9-10) ◽

pp. 341-348

Author(s):

V. Librando ◽

G. Magazzù ◽

A. Puglisi

Keyword(s):

Multivariate Data Analysis ◽

Partial Least Squares Regression ◽

Environmental Chemistry ◽

Sampling Site ◽

Principal Component ◽

Least Squares Regression ◽

Organic Micropollutants ◽

Suspended Material ◽

The Difference

The monitoring of water quality today provides a great quantity of data consisting of the values of the parameters measured as a function of time. In the marine environment, and especially in the suspended material, increasing importance is being given to the presence of organic micropollutants, particularly since some are known to be carcinogenic. As the number of measured parameters increases examining the data and their consequent interpretation becomes more difficult. To overcome such difficulties, numerous chemometric techniques have been introduced in environmental chemistry, such as Multivariate Data Analysis (MVDA), Principal Component Analysis (PCA) and Partial Least Squares Regression (PLSR). The use of the first technique in this work has been applied to the interpretation of the quality of Augusta bay, by measuring the concentration of numerous organic micropollutants, together with the classical water pollution parameters, in different sites and at different times. The MVDA has highlighted the difference between various sampling sites whose data were initially thought to be similar. Furthermore, it has allowed a choice of more significant parameters for future monitoring and more suitable sampling site locations.

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Membranes In Organic Micropollutants Removal

Current Organic Chemistry ◽

10.2174/1385272822666180419160920 ◽

2018 ◽

Vol 22 (11) ◽

pp. 1070-1102 ◽

Cited By ~ 8

Author(s):

Michal Bodzek ◽

Krystyna Konieczny

Keyword(s):

Organic Micropollutants

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Solid-phase extraction cartridges with multi-walled carbon nanotubes and effect of the oxygen functionalities on the recovery efficiency of organic micropollutants

Scientific Reports ◽

10.1038/s41598-020-79244-8 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Marta O. Barbosa ◽

Rui S. Ribeiro ◽

Ana R. L. Ribeiro ◽

M. Fernando R. Pereira ◽

Adrián M. T. Silva

Keyword(s):

Carbon Nanotubes ◽

Solid Phase Extraction ◽

Solid Phase ◽

Surface Groups ◽

Phase Extraction ◽

Organic Micropollutants ◽

Oxidation Method ◽

Hydrothermal Oxidation ◽

Multi Walled Carbon Nanotubes ◽

Walled Carbon Nanotubes

AbstractPristine and functionalized multi-walled carbon nanotubes (MWCNTs) were investigated as adsorbent materials inside solid-phase extraction (SPE) cartridges for extraction and preconcentration of 8 EU-relevant organic micropollutants (with different pKa and polarity) before chromatographic analysis of surface water. The recoveries obtained were > 60% for 5/8 target pollutants (acetamiprid, atrazine, carbamazepine, diclofenac, and isoproturon) using a low amount of this reusable adsorbent (50 mg) and an eco-friendly solvent (ethanol) for both conditioning and elution steps. The introduction of oxygenated surface groups in the carbon nanotubes by using a controlled HNO3 hydrothermal oxidation method, considerably improved the recoveries obtained for PFOS (perfluorooctanesulfonic acid) and methiocarb, which was ascribed to the hydrogen bond adsorption mechanism, but decreased those observed for the pesticide acetamiprid and for two pharmaceuticals (carbamazepine and diclofenac), suggesting π–π dispersive interactions. Moreover, a good correlation was found between the recovery obtained for methiocarb and the amount of oxygenated surface groups on functionalized MWCNTs, which was mainly attributed to the increase of phenols and carbonyl and quinone groups. Thus, the HNO3 hydrothermal oxidation method can be used to finely tune the surface chemistry (and texture) of MWCNTs according to the specific micropollutants to be extracted and quantified in real water samples.

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