Isolation of dissolved organic matter (dom) from surface waters using reverse osmosis and its impact on the reactivity of dom to formation and speciation of disinfection by-products

2001 ◽  
Vol 35 (9) ◽  
pp. 2225-2234 ◽  
Author(s):  
Mehmet Kitis ◽  
James E Kilduff ◽  
Tanju Karanfil
2013 ◽  
Vol 316-317 ◽  
pp. 323-326
Author(s):  
Chao Jie Zhang ◽  
Si Bo Li ◽  
Qian Chen ◽  
Qi Zhou

Dissolved organic matter (DOM) may do harms to human beings. After disinfected by chlorine (amine), DOM can form disinfection by-products (DBPs) which can be mutagenic, teratogenic and carcinogenic. Characterization and source of trihalomethane precursors in the secondary effluent by sequencing batch reactors were investigated. CHCl3 was the primary DBPs. The results showed that the precursors of CHCl3 were mainly strongly hydrophobic DOM, while CHCl2Br and CHClBr2 were mainly formed from hydrophilic DOM. The effects of different powder media (activated carbon, zeolite) on removal of DOM were compared. The results showed that the dosing of powder media can promote the removal of DOM and the DBPs precursors.


2014 ◽  
Vol 11 (10) ◽  
pp. 14097-14132 ◽  
Author(s):  
L. Tremblay ◽  
J. Caparros ◽  
K. Leblanc ◽  
I. Obernosterer

Abstract. Natural iron fertilization of high-nutrient low-chlorophyll (HNLC) waters induces annually occurring spring phytoplankton blooms off Kerguelen Islands (Southern Ocean). To examine the origin and fate of particulate and dissolved organic matter (POM and DOM), D- and L-amino acids (AA) were quantified at bloom and HNLC stations. Total hydrolysable AA accounted for 21–25% of surface particulate organic carbon (%POCAA) at the bloom sites, but for 10% at the HNLC site. A marked decrease in %POCAA with depth was observed at the most productive stations leading to values between 3 and 5% below 300 m depth. AA contributed to only 0.9–4.4% of dissolved organic carbon (%DOCAA) at all stations. The only consistent vertical trend was observed at the most productive station (A3-2) where %DOCAA decreased from ∼2% in the surface waters to 0.9% near 300 m. These AA yields and other markers revealed that POM and DOM were more rapidly altered or mineralized at the bloom sites compared to the HNLC site. Different molecular markers indicated that POM mostly originated from diatoms and bacteria. The estimated average proportion of POM from intact phytoplankton cells in surface waters was 45% at the bloom station A3-2, but 14% at the HNLC site. Estimates based on D-AA yields indicated that ∼15% of POM and ∼30% of DOM was of bacterial origin (cells and cell fragments) at all stations. Surprisingly, the DOM in HNLC waters appeared less altered than the DOM from the bloom, had slightly higher dissolved AA concentrations, and showed no sign of alteration within the water column. Unfavorable conditions for bacterial degradation in HNLC regions can explain these findings. In contrast, large inputs of labile organic molecules and iron, likely stimulate the degradation of organic matter (priming effect) and the production of more recalcitrant DOM (microbial carbon pump) during iron-fertilized blooms.


2015 ◽  
Vol 56 (69) ◽  
pp. 1-8 ◽  
Author(s):  
Mats A. Granskog ◽  
Daiki Nomura ◽  
Susann Müller ◽  
Andreas Krell ◽  
Takenobu Toyota ◽  
...  

AbstractAbsorption and fluorescence of chromophoric dissolved organic matter (CDOM) in sea ice and surface waters in the southern Sea of Okhotsk was examined. Sea-water CDOM had featureless absorption increasing exponentially with shorter wavelengths. Sea ice showed distinct absorption peaks in the ultraviolet, especially in younger ice. Older first-year sea ice had relatively flat absorption spectra in the ultraviolet range. Parallel factor analysis (PARAFAC) identified five fluorescent CDOM components, two humic-like and three protein-like. Sea water was largely governed by humic-like fluorescence. In sea ice, protein-like fluorescence was found in considerable excess relative to sea water. The accumulation of protein-like CDOM fluorescence in sea ice is likely a result of biological activity within the ice. Nevertheless, sea ice does not contribute excess CDOM during melt, but the material released will be of different composition than that present in the underlying waters. Thus, at least transiently, the CDOM introduced during sea-ice melt might provide a more labile source of fresher protein-like DOM to surface waters in the southern Sea of Okhotsk.


2019 ◽  
Vol 155 ◽  
pp. 300-309 ◽  
Author(s):  
Michael Gonsior ◽  
Leanne C. Powers ◽  
Ernest Williams ◽  
Allen Place ◽  
Feng Chen ◽  
...  

2020 ◽  
Vol 6 (9) ◽  
pp. 2365-2381
Author(s):  
Zachary T. Kralles ◽  
Kaoru Ikuma ◽  
Ning Dai

Peracetic acid pre-oxidation of algal impacted waters can reduce formation of trihalomethanes but promote formation of haloacetonitriles, due to the degradation of dissolved organic matter and coincident release of intracellular organic matter.


2013 ◽  
Vol 10 (11) ◽  
pp. 7207-7217 ◽  
Author(s):  
Y. Yamashita ◽  
Y. Nosaka ◽  
K. Suzuki ◽  
H. Ogawa ◽  
K. Takahashi ◽  
...  

Abstract. Chromophoric dissolved organic matter (CDOM) ubiquitously occurs in marine environments and plays a significant role in the marine biogeochemical cycles. Basin scale distributions of CDOM have recently been surveyed in the global ocean and indicate that quantity and quality of oceanic CDOM are mainly controlled by in situ production and photobleaching. However, factors controlling the spectral parameters of CDOM in the UV region, i.e., spectral slope of CDOM determined at 275–295 nm (S275–295) and the ratio of two spectral slope parameters (SR); the ratio of S275–295 to S350–400, have not been well documented. To evaluate the factor controlling the spectral characteristics of CDOM in the UV region in the open ocean, we determined the quantitative and qualitative characteristics of CDOM in the subarctic and subtropical surface waters (5–300 m) of the western North Pacific. Absorption coefficients at 320 nm in the subarctic region were higher than those in the subtropical region throughout surface waters, suggesting that magnitudes of photobleaching were different between the two regions. The values of S275–295 and SR were also higher in the subtropical region than the subarctic region. The dark microbial incubation showed biodegradation of DOM little affected S275–295, but slightly decreased SR. On the other hand, increases in S275–295 and relative stableness of SR were observed during photo-irradiation incubations respectively. These experimental results indicated that photobleaching of CDOM mainly induced qualitative differences in CDOM at UV region between the subarctic and subtropical surface waters. The results of this study imply that S275–295 can be used as a tracer of photochemical history of CDOM in the open ocean.


2012 ◽  
Vol 46 (11) ◽  
pp. 5806-5814 ◽  
Author(s):  
Jingdong Mao ◽  
Xueqian Kong ◽  
Klaus Schmidt-Rohr ◽  
Joseph J. Pignatello ◽  
E. Michael Perdue

2020 ◽  
Author(s):  
Angelica Bianco ◽  
Fabrizio Sordello ◽  
Mikael Ehn ◽  
Davide Vione ◽  
Monica Passananti

<p>The large production of plastic material (PlasticsEurope, 2019), together with the mishandling of plastic waste, has resulted in ubiquitous plastic pollution, which now reaches even the most remote areas of the Earth (Allen et al., 2019; Bergmann et al., 2019). Plastics undergo a slow process of erosion in the environment that decreases their size: microplastics (MPs) and nanoplastics (NPs) have diameters between 1 µm and 5 mm and lower than 1 µm, respectively (Frias and Nash, 2019).</p><p>The occurrence, transformation and fate of MPs and NPs in the environment are still unclear. Therefore, the objective of this work is to better understand the reactivity of NPs using an aqueous suspension of polystyrene NPs (PS-NPs) as a proxy, in the presence of sunlight and chemicals oxidants. The results obtained are relevant to both the atmospheric aqueous phase, such as cloud and fog droplets, and surface waters. We investigated the reactivity of PS-NPs with light and with two important oxidants in the environment: ozone (O<sub>3</sub>) and hydroxyl radicals (<sup>•</sup>OH). The adsorption of ozone (O<sub>3</sub>) on PS-NPs is investigated, showing a significant O<sub>3</sub> uptake. Moreover, for the first time, a reactivity constant with <sup>•</sup>OH is determined. We found a linear correlation between the kinetic constants measured for three different sizes of PS-NPs and the surface exposed by the particles. Degradation products (short chain carboxylic acids and aromatic compounds), obtained by direct and <sup>•</sup>OH-mediated photolysis of PS-NPs suspensions, are identified by high-resolution mass spectrometry. Irradiation of a PS-NPs suspension under natural sunlight for 1 year has shown the formation of formic acid and organic compounds similar to those found in riverine and cloud dissolved organic matter.</p><p>This work is crucial to assess the impact of NPs abiotic degradation in atmospheric and surface waters; indeed, the reactivity constant and the degradation products can be implemented in environmental models to estimate the contribution of NPs degradation to the natural dissolved organic matter in the aqueous phase. A preliminary simulation using APEX (Aqueous Photochemistry of Environmentally occurring Xenobiotics) (Bodrato and Vione, 2014) model shows that in NPs-polluted environments (10<sup>9</sup> particles mL<sup>-1</sup>) there is potential for NPs to significantly scavenge <sup>•</sup>OH, if the content of natural organic matter is not too high, as observed for surface and cloud water.</p><p>Allen, S., et al., 2019.  Nat. Geosci. 12, 339–344. https://doi.org/10.1038/s41561-019-0335-5<br>Bergmann, et al., 2019.  Sci. Adv. 5, eaax1157. https://doi.org/10.1126/sciadv.aax1157<br>Bodrato, M., Vione, D., 2014. Environ. Sci.: Processes Impacts 16, 732–740. https://doi.org/10.1039/C3EM00541K<br>Frias, J., Nash, R., 2019. Mar. Pollut. Bull. 138, 145–147. https://doi.org/10.1016/j.marpolbul.2018.11.022</p>


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