Chloroform—An Emerging Pollutant in the Air

Author(s):  
Abinaya Sekar ◽  
George K. Varghese ◽  
M. K. Ravi Varma
Keyword(s):  
Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 215
Author(s):  
Nina Finčur ◽  
Paula Sfîrloagă ◽  
Predrag Putnik ◽  
Vesna Despotović ◽  
Marina Lazarević ◽  
...  

Pharmaceuticals and pesticides are emerging contaminants problematic in the aquatic environment because of their adverse effects on aquatic life and humans. In order to remove them from water, photocatalysis is one of the most modern technologies to be used. First, newly synthesized photocatalysts were successfully prepared using a sol–gel method and characterized by different techniques (XRD, FTIR, UV/Vis, BET and SEM/EDX). The photocatalytic properties of TiO2, ZnO and MgO nanoparticles were examined according to their removal from water for two antibiotics (ciprofloxacin and ceftriaxone) and two herbicides (tembotrione and fluroxypyr) exposed to UV/simulated sunlight (SS). TiO2 proved to be the most efficient nanopowder under UV and SS. Addition of (NH4)2S2O8 led to the faster removal of both antibiotics and herbicide fluroxypyr. The main intermediates were separated and identified for the herbicides and antibiotic ciprofloxacin. Finally, the toxicity of each emerging pollutant mixture and formed intermediates was assessed on wheat germination and biomass production.


Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3422
Author(s):  
Giovanni Luongo ◽  
Lorenzo Saviano ◽  
Giovanni Libralato ◽  
Marco Guida ◽  
Antonietta Siciliano ◽  
...  

In recent years, many studies have reported the frequent detection of antihypertensive agents such as sartans (olmesartan, valsartan, irbesartan and candesartan) in the influents and effluents of wastewater treatment plants (WWTPs) and in the superficial waters of rivers and lakes in both Europe and North America. In this paper, the degradation pathway for candesartan (CAN) was investigated by simulating the chlorination process that is normally used to reduce microbial contamination in a WWTP. Twelve isolated degradation byproducts (DPs), four of which were isolated for the first time, were separated on a C-18 column by employing a gradient HPLC method, and their structures were identified by combining nuclear magnetic resonance and mass spectrometry and comparing the results with commercial standards. On the basis of these results, a mechanism of formation starting from the parent drug is proposed. The ecotoxicity of CAN and its DPs was studied by conducting a battery of ecotoxicity tests; bioassays were performed using Aliivibrio fischeri (bacterium), Daphnia magna (planktonic crustacean) and Raphidocelis subcapitata (alga). The ecotoxicity results shed new light on the increased toxicity of DPs compared with the parent compound.


2018 ◽  
Vol 42 (19) ◽  
pp. 15778-15783 ◽  
Author(s):  
Daniela Intrieri ◽  
Caterina Damiano ◽  
Silvia Rizzato ◽  
Roberto Paolesse ◽  
Mariano Venanzi ◽  
...  

The synthesis of a porphyrin chemosensor is here reported as well as its sensing activity in detecting the emerging pollutant diclofenac with an overall 1 : 1 binding constant of about 105 M−1.


2019 ◽  
Vol 7 (9) ◽  
pp. 304 ◽  
Author(s):  
Bo Ram Kang ◽  
Soo Bin Kim ◽  
Hyun A Song ◽  
Tae Kwon Lee

High-density polyethylene (HDPE) is a widely used organic polymer and an emerging pollutant, because it is very stable and nonbiodegradable. Several fungal species that produce delignifying enzymes are known to be promising degraders of recalcitrant polymers, but research on the decomposition of plastics is scarce. In this study, white rot fungus, Bjerkandera adusta TBB-03, was isolated and characterized for its ability to degrade HDPE under lignocellulose substrate treatment. Ash (Fraxinus rhynchophylla) wood chips were found to stimulate laccase production (activity was > 210 U/L after 10 days of cultivation), and subsequently used for HDPE degradation assay. After 90 days, cracks formed on the surface of HDPE samples treated with TBB-03 and ash wood chips in both liquid and solid states. Raman analysis showed that the amorphous structure of HDPE was degraded by enzymes produced by TBB-03. Overall, TBB-03 is a promising resource for the biodegradation of HDPE, and this work sheds light on further applications for fungus-based plastic degradation systems.


2020 ◽  
Vol 4 (2) ◽  
pp. 51 ◽  
Author(s):  
Mohamed Kiari ◽  
Raúl Berenguer ◽  
Francisco Montilla ◽  
Emilia Morallón

The hybridization of clay minerals with conducting polymers receives great interest for different potential applications, including environmental remediation. This work studies and compares the electrochemical properties of two different clays, montmorillonite (Mont) and diatomite (Diat), and their respective clay/PEDOT-PSS hybrid materials in H2SO4 medium. The hybrid materials were prepared by electropolymerization of EDOT in the presence of PSS. The physico-chemical and electrochemical properties of both clays were analyzed by different techniques, and the influence of the clay properties on electropolymerization and the electroactivity of the resulting clay/PEDOT-PSS hybrids was investigated. Specifically, the Fe2+/Fe3+ redox probe and the oxidation of diclofenac, as a model pharmaceutical emerging pollutant, were used to test the electron transfer capability and oxidative response, respectively, of the clay/PEDOT-PSS hybrids. The results demonstrate that, despite its low electrical conductivity, the Mont is an electroactive material itself with good electron-transfer capability. Conversely, the Diat shows no electroactivity. The hybridization with PEDOT generally enhances the electroactivity of the clays, but the clay properties affect the electropolymerization efficiency and hybrids electroactivity, so the Mont/PEDOT displays improved electrochemical properties. It is demonstrated that clay/PEDOT-PSS hybrids exhibit diclofenac oxidation capability and diclofenac concentration sensitivity.


RSC Advances ◽  
2020 ◽  
Vol 10 (65) ◽  
pp. 39931-39942
Author(s):  
Irwing M. Ramirez-Sanchez ◽  
Onur G. Apul ◽  
Navid B. Saleh

Micron-scale brass is a catalyst that can be activated with ultraviolet radiation to remove emerging contaminants from water via oxidation by hydroxyl radicals.


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