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Aquatic ecosystems and potable water are being exploited and depleted due to urbanization and the encouragement of extensive industrialization, which induces the scarcity of pure water. However, current decontamination methods are limited and inefficient. Various innovative remediation strategies with novel nanomaterials have recently been demonstrated for wastewater treatment. Carbon dots (C-dots) and graphene quantum dots (GQ-dots) are the most recent frontiers in carbon nanomaterial-based adsorption studies. C-dots are extremely small (1–10 nm) quasi-spherical carbon nanoparticles (mostly sp3 hybridized carbon), whereas GQ-dots are fragments of graphene (1–20 nm) composed of primarily sp2 hybridized carbon. This article highlights the function of C-dots and GQ-dots with their specifications and characteristics for the efficient removal of organic and inorganic contaminants in water via adsorption chromatography. The alteration of adsorption attributes with the hybrid blending of these dots has been critically analyzed. Moreover, various top-down and bottom-up approaches for synthesizing C-dots and GQ-dots, which ultimately affect their morphology and structure, are described in detail. Finally, we review the research deficit in the adsorption of diverse pollutants, fabrication challenges, low molecular weight, self-agglomeration, and the future of the dots by providing research prospects and selectivity and sensitivity perspectives, the importance of post-adsorption optimization strategies and the path toward scalability at the tail of the article. [ABSTRACT FROM AUTHOR]

Hen eggs play a vital role in the human diet and their safety is critical to avoid the risk of foodborne illness for consumers. Engineered Water Nanostructures (EWNS) generated via an electrospray system is a novel and nanotechnology-based technique, which can be utilized for inactivating bacteria. The primary objective of this work was to assess this technique's effectiveness as a chemical-free and non-thermal approach for decontaminating egg surfaces and investigate its potential as an alternative to the conventional method of washing eggs. The results showed that under EWNS operating conditions of 5 min of exposure time, 1 μL/min/needle of water flow rate, and 9.0 kV/cm of electric field strength, the highest inactivation efficiency of 97.6 and 80.4% were obtained for decontaminating egg surfaces contaminated by E. coli and Salmonella spp., respectively. Results also proved no significant difference in physical properties, chemical components, and eggshell cuticle coverage of EWNS-treated eggs compared to unwashed eggs. • Engineered water nanostructures (EWNS) produced from electro spray were used to decontaminate eggshell. • Representative pathogens on eggshell were decontaminated. • EWNS do not show any impact on physical and chemical properties of treated eggs. • A chemical-free surface decontamination method was developed. [ABSTRACT FROM AUTHOR]

The contamination of water with organic pollutants such as dyes and phenols is a serious environmental problem, requiring effective treatment methods. In the present study, a novel nanocomposite was synthesized by intercalating graphene oxide and bentonite clay into MgFeAl-layered triple hydroxide (GO/BENT/LTH), which was characterized using different techniques. The adsorption efficacy of the GO/BENT/LTH nanocomposite was assessed via the removal of two harmful organic water pollutants, namely methyl orange (MO) and 2-nitrophenol (2NP). The obtained results revealed that the maximum adsorption capacities (q max) of MO and 2NP reached 3106.3 and 2063.5 mg/g, respectively, demonstrating the excellent adsorption performance of the nanocomposite. Furthermore, this study examined the effects of contact time, initial MO and 2NP concentrations, pH, and temperature of the wastewater samples on the adsorptive removal of MO and 2NP by the GO/BENT/LTH nanocomposite. The pH, zeta potential, and FTIR investigations suggested the presence of more than one adsorption mechanism. Thermodynamic investigations elucidated the exothermic nature of the adsorption of MO and 2NP onto the GO/BENT/LTH nanocomposite, with MO adsorption being more sensitive to temperature change. Additionally, regeneration studies revealed a marginal loss in the MO and 2NP removal with the repetitive use of the GO/BENT/LTH nanocomposite, demonstrating its reusability. Overall, the findings of this study reveal the promise of the GO/BENT/LTH nanocomposite for effective water decontamination. • Novel GO/clay/MgFeAl-LTH nanocomposites is synthesized and characterized herein. • The nanocomposite outperformed its parental materials and their binary combinations. • The q max of MO and 2NP using this nanocomposite are >3000 and > 2000 mg/g, respectively. • Both pollutants adsorb spontaneously and exothermically on the nanocomposite. • The nanocomposite can be used multiple times with insignificant performance loss. [ABSTRACT FROM AUTHOR]

The excessive and uncontrollable discharge of diverse organic pollutants into the environment has emerged as a significant concern, presenting a substantial risk to human health. Among the advanced oxidation processes used for the purification of wastewater, cold plasma technology is superior in fast and effective decontamination but often fails facing mixed pollutants. To address these issues, here we develop the new conceptual approach, plasma process, and proprietary reactor that ensure, for the first time, that the efficiency of treatment (114.7%) of two mixed organic dyes, methylene blue (MB) and methyl orange (MO), is higher than when the two dyes are treated separately. We further reveal the underlying mechanisms for the energy-efficient complete degradation of the mixed dyes. The contribution of plasma-induced ROS and the distinct degradation characteristics and mechanism of pollutants in mixed treatment are discussed. The electron transfer pathway revealed for the first time suggest that the mixed pollutants reduce the overall redox potentials and facilitate electron transfer during the plasma treatment, promoting synergistic degradation effects. The integrated frameworks including both direct and indirect mechanisms provide new insights into the high-efficiency mixed-contaminant treatment. The degradation products for mixed degradation are revealed based on the identification of intermediate species. The plasma-treated water is proven safe for living creatures in waterways and sustainable fishery applications, using in vivo zebrafish model bio-toxicity assay. Overall, these findings offer a feasible approach and new insights into the mechanisms for the development of highly-effective, energy-efficient technologies for wastewater treatment and reuse in agriculture, industry, and potentially in urban water networks. [Display omitted] • The mixed treatment exhibited significant efficiency improvements (114.7%) than the separate treatment. • Unveiled synergistic ROS and electron transfer mechanism during plasma treatment. • Confirmed treated solution's biosafety via in vivo zebrafish tests and ECOSAR model. • Results offer data and theory for feasible engineering applications. [ABSTRACT FROM AUTHOR]

Here, we have demonstrated an innovative decontamination strategy using molten salts as a solvent to clean stubborn uranium contaminants on stainless steel surfaces. The aim of this work was to investigate the evolutionary path of contaminants in molten salts to reveal the decontamination mechanism, thus providing a basis for the practical application of the method. Thermodynamic analysis revealed that alkali metal hydroxides, carbonates, chlorides and nitrates can react with uranium oxides (UO 3 and U 3 O 8) to form various uranates. Notably, the decontamination mechanism was elucidated by analyzing the chemical composition of the contaminants in the molten salts and the surface morphology of the specimens considering NaOH–Na 2 CO 3 –NaCl melt as the decontaminant. The decontamination process involved two stages: a rapid decontamination stage dominated by the thermal effect of molten salt, and a stable decontamination stage governed by the chemical reactions and diffusion of molten salt. Subsequently, a multiple decontamination strategy was implemented to achieve high decontamination rates and low residual radioactivity. Within the actual cleaning time of 30 min, the decontamination efficiency (DE) of UO 3 -contaminated specimens reached 97.8% and 93.0% for U 3 O 8 -contaminated specimens. Simultaneously, the radioactivity levels of all specimens were reduced to below the control level for reuse in the nuclear domain. Particularly, the actual radioactive waste from the nuclear industry reached a reusable level of radioactivity after decontamination. The NaOH–Na 2 CO 3 –NaCl melt outperforms conventional chemical solvents and may be one of the most rapid and efficient decontaminants for stubborn uranium contamination of metal surfaces, which provides insights in regard to handling nuclear waste. [Display omitted] • Molten salts provided efficient and rapid removal of radioactive contamination. • The first reported mechanism of uranium contaminant removal by molten salts. • Highly reactive molten salts can form uranates with uranium contaminants. • The decontaminated specimens can be reused in the nuclear industry. [ABSTRACT FROM AUTHOR]

Fresh produce is still a food safety concern as it can be contaminated by bacterial pathogens. Most of these products cannot be pasteurized, making the application of a washing step essential for food safety. Commercial disinfectants can become a hazard for the consumer, which motivates this study to evaluate alternative washing solutions based on nanoemulsified oregano and rosemary essential oils (EOs) for the decontamination of E. coli O157:H7 on cherry tomatoes. Every washing solution was more effective than tap water, and the origin of the EOs (Romania or Spain) did not influence their antibacterial activity. The efficacy was depended on the concentration, with the highest oregano EO nanoemulsion concentration (10%) having a disinfectant effect equivalent to commercial chlorine solution (∼3.5 log CFU), while a 10% rosemary EO solution was less effective (∼2.5 log CFU). Using a QMRA model, it can be concluded that the consumer risk to E. coli O157:H7 would not increase by substituting the commercial chlorine-based solution with the 10% oregano EO-based nanoemulsion. In conclusion, although further research is still needed to fully assess its industrial implementation, the washing solutions based on EOs nanoemulsions developed in this study could be an alternative to the current chlorine commercial products for produce. • A washing step is crucial to ensure the safety of cherry tomatoes against E. coli O157:H7. • Washing solution with 0.33% nanoemulsified EO are equivalent to water washing. • Washing solutions with 10% nanoemulsified oregano are equivalent to commercial ones. • Nanoemulsified oregano can be an alternative to chlorine compounds for washing solutions. [ABSTRACT FROM AUTHOR]

Disinfection and decontamination of water by application of oxidisers is an essential treatment step across numerous industrial sectors including potable supply and industry waste management, however, could be greatly enhanced if operated as advanced oxidation processes (AOPs). AOPs destroy contaminants including pathogens by uniquely harnessing radical chemistry. Despite AOPs offer great practical opportunities, no reviews to date have highlighted the critical AOP virtues that facilitate AOPs' scale up under growing industrial demand. Hence, this review analyses the critical AOP parameters such as oxidant conversion efficiency, batch mode vs continuous-flow systems, location of radical production, radical delivery by advanced micro-/mesoporous structures and AOP process costs to assist the translation of progressing developments of AOPs into their large-scale applications. Additionally, the state of the art is analysed for various AOP inducing radical/oxidiser measurement techniques and their half-lives with a view to identify radicals/oxidisers that are suitable for in-situ production. It is concluded that radicals with short half-lives such as hydroxyl (10−4 μsec) and sulfate (30–40 μsec) need to be produced in-situ via continuous-flow reactors for their effective transport and dosing. Meanwhile, radicals/oxidisers with longer half-lives such as ozone (7–10 min), hydrogen peroxide (stable for several hours), and hypochlorous acid (10 min −17 h) need to be applied through batch reactor systems due to their relatively longer stability during transportation and dosing. Complex and costly synthesis as well as cytotoxicity of many micro-/mesoporous structures limit their use in scaling up AOPs, particularly to immobilising and delivering the short-lived hydroxyl and sulfate radicals to their point of applications. Overall, radical delivery using safe and advanced biocompatible micro-/mesoporous structures, radical conversion efficiency using advanced reactor design and portability of AOPs are priority areas of development for scaling up to industry. [Display omitted] • Radical conversion, location, delivery, operating mode and cost affect scalability • Radicals with short half-lives need to be produced in-situ via continuous mode • Radicals/oxidisers with longer half-lives need to be applied through batch systems • Conversion efficiency and portability of AOPs are priority areas of development [ABSTRACT FROM AUTHOR]

Ca 2 Nb 3 O 10 − nano-sheets can be produced via the stirring of HCa 2 Nb 3 O 10 ·1.5H 2 O and tetrabutylammonium hydroxide mixture, which is a time-consuming process. The aim of the present study is to propose a facile and rapid route for the Ca 2 Nb 3 O 10 − fabrication. KCa 2 Nb 3 O 10 was firstly synthesized via a solid-state reaction. The synthesized KCa 2 Nb 3 O 10 was then protonated and exfoliated under the ultrasonic irradiation. The results revealed that the conversion of KCa 2 Nb 3 O 10 to Ca 2 Nb 3 O 10 − nano-sheets, with 94% exfoliation efficiency, is achievable after only 12 ​h of ultrasonic treatment (i.e. 6 h protonation +6 ​h exfoliation) which is the shortest time reported so far. The ultrasonically produced Ca 2 Nb 3 O 10 − suspension was stable and showed the capability to be utilized for the removal of hazardous ions (i.e. Cs+) from the wastewater. The produced Ca 2 Nb 3 O 10 − nano-sheets also had smaller sizes, comparing to the nano-sheets produced via stirring method. KCa 2 Nb 3 O 10 powder was successfully converted to Ca 2 Nb 3 O 10 − nano-sheets using a laboratory ultrasonic cleaner. Image 1 • KCa 2 Nb 3 O 10 is converted to Ca 2 Nb 3 O 10 − nano-sheets using the ultrasonic-treatment. • This method has much higher exfoliation efficiency comparing to the stirring. • The process accomplished after only 12 h. • Produced Ca 2 Nb 3 O 10 − nano-sheets can be utilized for Cs+ ion decontamination. [ABSTRACT FROM AUTHOR]

This study evaluated the efficacy of alkyltrimethylammonium-bromide (ATMB) and chlorhexidine-digluconate (CDG) to reduce pathogens of meat safety concerns in solution and on hides. In solution, ATMB at 50 and 250 ppm reduced individual cocktails of Salmonella enterica , Escherichia coli O157:H7 and Listeria monocytogenes at averages of 1.77 and 3.76, 1.11 and 5.78, 0.52 and 2.55 log CFU/mL respectively after 5 min, where CDG at 250 and 500 ppm reduced S. enterica and E. coli O157:H7 at averages of 1.14 and 2.52, 1.00 and 1.63 log CFU/mL respectively. Treatment with 6,000 ppm ATMB for 5 min reduced S. enterica , E. coli and L. monocytogenes on inoculated hide surfaces at averages of 0.40, 1.77 and 2.05 log CFU/cm2 respectively, relative to a water-only control. Similarly, 1,000 ppm CDG resulted maximum reductions in S. enterica , E. coli of 2.82, 2.41 log CFU/cm2 in 5 min and L. monocytogenes of 2.18 log CFU/cm2 in 3 min respectively from the inoculated haired surface of hide. • The efficacy of two antimicrobials (ATMB & CDG) on pathogen reduction are tested. • Treatment reduces Salmonella enterica , Escherichia coli O157:H7 and Listeria monocytogenes. • Reduction of pathogens in solution and on haired surface of hide is observed in short time. • Non-toxic cattle decontamination spray formulation can potentially be developed. [ABSTRACT FROM AUTHOR]

Fe-doped carbon xerogels with a highly developed graphitic structure were synthesized by a one-step sol-gel polymerization. These highly graphitic Fe-doped carbons are presented as promising dual-functional electro-Fenton catalysts to perform both the electro-reduction of O 2 to H 2 O 2 and H 2 O 2 catalytic decomposition (Fenton) for wastewater decontamination. The amount of Fe is key to the development of this electrode material, since affects the textural properties; catalyzes the development of graphitic clusters improving the electrode conductivity; and influences the O 2 -catalyst interaction controlling the H 2 O 2 selectivity but, at the same time is the catalyst for the decomposition of the electrogenerated H 2 O 2 to OH• radicals for the organic pollutants oxidation. All materials achieve the development of ORR via the 2-electron route. The presence of Fe considerably improves the electro-catalytic activity. However, a mechanism change seems to occur at around −0.5 V in highly Fe-doped samples. At potential lower than −0.5 eV, the present of Feδ+ species or even Fe–O–C active sites favour the selectivity to 2e-pathway, however at higher potentials, Feδ+ species are reduced favoring a O–O strong interaction enhancing the 4e-pathway. The Electro-Fenton degradation of tetracycline was analyzed. The TTC degradation is almost complete (95.13%) after 7 h of reaction without using any external Fenton-catalysts. [Display omitted] • Fe-doped carbon gels with a highly developed graphitic structure were synthesized. • The presence of Fe considerably improves the electro-catalytic activity. • The present of Feδ+ or Fe–O–C active sites favour the selectivity to 2e-pathway. • Almost total TTC degradation (95.13%) is achieved after 7 h of reaction. • Fe-doped carbon are excellent dual-functional catalysts for water decontamination. Synopsis:Fe-doped carbon xerogels with a highly developed graphitic structure were synthesized and evaluated as promising dual-functional electrodes for wastewater decontamination. [ABSTRACT FROM AUTHOR]

Abstract High voltage atmospheric cold plasma (HVACP) is a novel technology which has shown promising results on microbial inactivation under low temperature, and thus offers opportunities on decontamination of biological materials. In this study, Listeria innocua spot inoculated tryptic soy agar (TSA), Queso Fresco cheese (QFC) and cheese model (CM) samples were treated with HVACP under direct and indirect mode of exposure in dry air gas environment for 5 min. After direct HVACP treatment, a reduction of 5.0, 3.5 and 1.6 log 10 CFU/g was observed for TSA, CM and QFC, respectively. Direct plasma treatment was more effective in Listeria innocua inactivation on CM and QFC compared to indirect treatment. Surface analysis has shown that the differences in surface roughness and micro-structure of the substrate hugely impact the efficacy of the HVACP treatment by affecting the attachment of the bacteria cells on the surface and providing protective locations for the microbes within the surface. Highlights • Achieved significant inactivation of Listeria innocua on QFC, CM and TSA by cold plasma. • Surface topography significantly affects the inactivation of Listeria innocua by cold plasma. • Direct plasma treatment was found to be more effective for inactivation than indirect treatment. [ABSTRACT FROM AUTHOR]

Arsenic contamination due to anthropogenic and natural activities has posted a great risk to humans through several pathways. As such, development of cost-effective technologies for arsenic decontamination is very important from both social and economic standpoints. In this paper, we are reporting a novel adsorptive yttrium nanoparticles (YNPs)/polyvinyl alcohol (PVA) modified polysulfone (PSF) membrane for the efficient treatment of arsenic. In the preparation of membrane, the porous PSF membrane fabricated with hydrophilic polyacrylic acid (PAA) polymer was coated by a PVA thin layer and then loaded with YNPs through an in-situ precipitation method using an ammonia vapor. We found that spherical YNPs were uniformly distributed onto the surface and within the matrix of membrane. The adsorption capacity as high as 35.56 mg-As/g was obtained at pH around 7. The membrane worked well across pH 4.0–8.0, with the best performance at pH 5.0. 90% of ultimate adsorption capacity was achieved in 2 h with the initial arsenic concentration of 10 mg/L and at the membrane dosage of 0.2 g/L. The kinetics data can be better fitted by the pseudo-second-order model. The Langmuir isotherm well described the adsorption isothermal data. The filtration studies with an initial arsenate concentration of 94.8 μg/L showed that the treatment capacities of the composite membrane at pH 7.0 and 5.0 were 296 and 692 L/m 2 , respectively. The X-ray photoelectron spectroscopy (XPS) analysis suggested that ligand exchange between yttrium-hydroxyl groups and arsenate species may play as the main adsorption mechanism. Our study demonstrates that the membrane is a better material for arsenic decontamination than previously reported adsorptive membranes. [ABSTRACT FROM AUTHOR]

The discharge of inadequately treated or untreated industrial wastewaters has greatly contributed to the release of contaminants into the environment, including toxic metals. Toxic metals are persistent and bioaccumulative, being their removal from wastewaters prior to release into water bodies of great concern. Literature reports the use of brown marine macroalgae for toxic metals removal from aqueous solutions as an economic and eco-friendly technique, even when applied to diluted solutions. Minor attention has been given to the application of this technique in the treatment of real wastewaters, which present a complex composition that can compromise the biosorption performance. Therefore, the main goal of this comprehensive review is to critically outline studies that: (i) applied brown marine macroalgae as natural cation exchanger for toxic metals removal from real and complex matrices; (ii) optimised the biosorption process in a fixed-bed column, which was further scaled-up to pilot plants. An overview of toxic metals sources, chemistry and toxicity, which are relevant aspects to understand and develop treatment techniques, is initially presented. The problem of water resources pollution by toxic metals and more specifically the participation of metal finishing industries in the environmental contamination are issues also covered. The current and potential decontamination methods are presented including a discussion of their advantages and drawbacks. The literature on biosorption was reviewed in detail, considering especially the ion exchange properties of cell wall constituents, such as alginate and fucoidan, and their role in metal sequestration. Besides that, a detailed description of biosorption process design, especially in continuous mode, and the application of mechanistic models is addressed. [ABSTRACT FROM AUTHOR]

The broad bandgap tin (IV) oxide (SnO 2 ) is the least investigated semiconductor material for photocatalytic water decontamination in sunlight exposure. A detailed study covering the synthesis, characterization and the evaluation of photocatalytic activity of SnO 2 , in the natural sunlight exposure, is presented. The structural characterization by XRD revealed the formation of phase pure tetragonal SnO 2 with the average crystallite size of ∼41.5 nm whereas minor Sn 2+ states in the material were identified by XPS analysis. As explored by diffuse reflectance (DR) and photoluminescence (PL) spectroscopy, the material exhibited a distinct absorption edge at ∼3.4 eV. The morphological and microstructure analysis of the synthesized SnO 2 was carried out by FESEM and HRTEM. The electrochemical impedance spectroscopy (EIS) and chronopotentiometry (CP) predicted the better charge transport and retention ability of the material under illumination whereas the Mott-Schottky extrapolation prophesied the n-type behavior with the flat-band potential of −0.60 V. The photocatalytic activity of SnO 2 was assessed in the exposure of complete spectrum natural sunlight for the removal of 2,4,6-trichlorophenol. The HPLC and TOC analysis monitored the progress of degradation and mineralization whereas the released chloride ions were evaluated by ion chromatography. The effect of the transition metal ions (Fe 3+ , Cu 2+ , Ni 2+, and Zn 2+ ) as electron capture agents and H 2 O 2 as ROS generator was explored during the degradation process. The utility of the material for the simultaneous removal of chlorophenols in the mixture was also investigated. The SnO 2 exhibited sustained activity in the repeated use. Based on experimental evidence congregated, the mechanism of the removal process and the efficacy of SnO 2 for sunlight photocatalytic decontamination of water was established. [ABSTRACT FROM AUTHOR]

Visible-light-driven (VLD) Ag/AgBr/ZnFe 2 O 4 composites with different weight ratios of ZnFe 2 O 4 were synthesized via a facile hydrothermal method. The ZnFe 2 O 4 was evenly dispersed on the surface of Ag/AgBr particles with the diameter about 20 nm. The obtained Ag/AgBr/ZnFe 2 O 4 composites exhibited the high bacterial disinfection efficiency and inactivated bacteria after 120 min visible illumination, which was better than those of with pure ZnFe 2 O 4 and Ag/AgBr. Due to the introduction of ZnFe 2 O 4 , the Ag/AgBr/ZnFe 2 O 4 inactivated bacterial cells through the generation of H 2 O 2 , which generated from the electron reduction on the conduction band of ZnFe 2 O 4 in the system. The photocatalytic experiments indicated that as-prepared samples showed the good photocatalytic performance toward degradation of methyl orange (MO) dye. In a word, the Ag/AgBr/ZnFe 2 O 4 composites, as the antibacterial photocatalyst, is a promising candidate material in wastewater decontamination. [ABSTRACT FROM AUTHOR]

The oil reservoir drilling phase generates contaminated cuttings with oil formation itself. These cuttings must be subjected to a decontamination process before being disposed of in the environment. Several technologies are cited in literature for the remediation of soil contaminated with oil or diesel, but none have been reported to remedy drill cuttings contaminated with oil from reservoir. The reservoir drill cuttings are a problem because its discharge is not allowed. The drying technology using microwave has shown promise in the decontamination of cuttings with non-aqueous base drilling fluid, conciliating good robustness and high removal efficiency. Considering the aspects mentioned previously, the application of heating and drying technology using microwave in the remediation of oil contaminated cuttings from well drill was studied. The influence of temperature, specific energy and initial content of water in the drying operation of the reservoir cuttings and of the drilling cuttings artificially contaminated with oil were analyzed. The results showed an influence of temperature in the drying of the cuttings, being necessary to reach the boiling temperature of heavier hydrocarbons to reach an efficient removal in the operation. The specific energy has a strong influence, reaching a total decontamination using 2.67 kWh/kg. The initial water content was effective in removing oil, reducing the residual level of oil with the increase of initial content of water. It also modifies the temperature profiles of the kinetic-warming of the contaminated cuttings. Both the technology and the equipment used proved effective for obtaining total decontamination of oil from the cuttings. [ABSTRACT FROM AUTHOR]

The dispersion-corrected density functional theory (DFT-D3) is used to investigate the mechanism of mesoporous pulp waste (MPW) and polyaniline (PANI) adsorptive removal methyl orange (MO) dye from their aqueous solutions. The results are absolutely reliable because of the sufficiently accurate method although such big systems are studied. It is demonstrated that hydrogen bond and Van Der Waals interactions play a significant role in MO adsorption by MPW and PANI. For MO adsorption by MPW, hydrogen bond and Van Der Waals interactions are both weakened in S 1 state. In contrast, hydrogen bond and Van Der Waals interactions between PANI and MO are both enhanced in S 1 state. The thermodynamic parameters such as enthalpy and free energy change reveal that the MO adsorption by MPW and PANI are spontaneous and exothermic. The adsorption of MO on MPW is less favorable in S 1 state and the adsorption of MO on PANI is more favorable in S 1 state. Therefore, the photoexcitation should be controlled during the MO adsorption by MPW and applied for MO adsorption by PANI. [ABSTRACT FROM AUTHOR]

Organic arsenic in waters has been a global concern in drinking water due to its higher toxicity to humans. In this study, a novel zirconium/polyvinyl alcohol (PVA) modified polyvinylidene fluoride (PVDF) membrane was applied to remove organic arsenic from water. The impregnation of zirconium ions within the modified membrane was attributed to the coordination reactions among the zirconium ions, ether and hydroxyl groups. The synthesized membrane worked better at the acidic conditions and achieved the optimal uptake for both monomethylarsonic (MMA) and dimethylarsinic (DMA) at pH 2.0. The adsorption isotherm study demonstrated that the adsorption of both organic arsenic species was controlled by the mono-layer adsorption process; the maximum adsorption capacities for MMA and DMA were 73.04 and 37.53 mg/g at pH 2, and 29.78 and 19.03 mg/g at pH 7.0, respectively. The presence of humic acid had a negligible impact on the uptake of organic arsenic, whereas varying impacts on the arsenic adsorption were observed due to the presence of coexisting anions such as fluoride, phosphate, carbonate and silicate. A single piece of membrane with a surface area of only 12.56 cm 2 could treat 7.5-L MMA and 4.1-L DMA solution with an influent concentration of about 100 μg/L to meet the WHO and USEPA standard of 10 μg/L. Based on the XPS analyses, the ion exchange reaction between chloride ions on the membrane surface and organic arsenic species was responsible for the removal of both MMA and DMA. [ABSTRACT FROM AUTHOR]

To investigate the effect of residual coagulant after coagulation pretreatment on activated sludge system of wastewater treatment plants (WWTPs), comparative evaluation of lab-scale sequencing batch reactors under different poly-aluminum chloride (PAC) concentrations (20 and 55 mg/L), presenting the performance differences of reactors. Results showed that the PAC concentration of 20 mg/L slightly enhanced the average removal efficiencies of chemical oxygen demand (COD) and total nitrogen (TN), up to 93.43% and 72.52%. Whereas, an inhibition effect was exerted at the PAC concentration of 55 mg/L, the average removal efficiencies decreased to 88.56% and 57.80% respectively. Similarly, the residual aluminum salts showed a concentration effect of low promotion and high inhibition on sludge activity index. The content of specific oxygen utilization rate (SOUR) and dehydrogenase (DHA) sharply decreased by 30.17% and 53.56% under the high PAC concentration of 55 mg/L. Activity recovery phase showed that the suppression of aluminum salt coagulant on biological system was reversible. High-throughput sequencing presented that the relative abundance of microbes showed obvious variations at different PAC concentrations, and certain bacteria in Chloroflexi and Bacteroidota exhibited better adaptability to the high PAC concentration environment. Nevertheless, the antagonism action between denitrifying genera and other genera as well as the downregulation of functional enzymes regarding nitrogen metabolism gave rise to the deterioration of denitrification under the high PAC concentration of 55 mg/L. This study revealed the influence mechanism of residual aluminum salt coagulant on activated sludge system, providing strategies for efficient decontamination and long-term stable operation of biological system in wastewater treatment plant under the condition of adding PAC. • High concentration of PAC affected organics and nitrogen removal. • The suppression of aluminum salt coagulant on pollutant removal was reversible. • Microbial community structure changed at different PAC concentration. • High PAC concentration inhibited the sludge activity and microbial metabolism. [ABSTRACT FROM AUTHOR]

A possibility of using simultaneous sewage sludge digestion and metal leaching (SSDML) process at the thermophilic temperature to remove heavy metals and suspended solids from sewage sludge is explored in this study. Though thermophilic sludge digestion efficiently produces a stable sludge, its inability to remove heavy metals requires it to be used in tandem with another process like bioleaching for metal reduction. Previously, different temperature optima were known for the heterotrophs (thermophilic) responsible for the sludge digestion and the autotrophs involved in bioleaching (mesophilic), because of which the metal concentration was brought down separately in a different reactor. In our study, SSDML process was carried out at 50 °C (thermophilic) by using ferrous sulfate (batch-1) and sulfur (batch-2) as the energy source in two reactors. The concentration of volatile suspended solids reduced by >40% in both batches, while that of heavy metals zinc, copper, chromium, cadmium and nickel decreased by >50% in both batch-1 and batch-2. Lead got leached out only in batch-1. Using 16S rRNA gene-based PCR-denaturing gradient gel electrophoresis analysis, Alicyclobacillus tolerans was found to be the microorganism responsible for lowering the pH in both the reactors at thermophilic temperature. The indicator organism count was also below the maximum permissible limit making sludge suitable for agricultural use. Our results indicate that SSDML at thermophilic temperature can be effectively used for reduction of heavy metals and suspended solids from sewage sludge. [ABSTRACT FROM AUTHOR]

A series of nanocomposite adsorbents were prepared by heterocoagulation of negatively charged delaminated montmorillonite (M t ) and positively charged synthetic layered double hydroxide (LDH) colloids with different LDH loading amounts. The mineralogy and physicochemical properties of the resulting nanocomposites were characterized. Their potential applications for phosphate (P) removal from aqueous solution, as a function of P concentration (2.5–200 mg/L), contact time (1 min–48 h) and pH (3–10), were evaluated by using batch adsorption modes. It was found that the adsorption data could be well described by both Freundlich and Langmuir isotherm models. The maximum adsorption capacity of three different LDH heterocoagulated montmorillonites (LDH-M ts ) for P removal was found to increase with LDH loadings, reaching 12.6, 16.2 and 23.3 mg/g respectively; Adsorption kinetic data revealed that 90% of adsorption onto LDH-M ts was completed within 1 h (h) and the adsorption process could be well described by the pseudo-second-order model. These results demonstrated that heterocoagulation of M t and LDH could preserve the adsorption capacity of LDH for P and enhance the stability of both clay minerals, and LDH-M ts could be effectively used as a potential promising filtration medium for P removal. [ABSTRACT FROM AUTHOR]

The aim of the present study is to develop an efficient nanomaterial for the removal of fluoride and disinfection of harmful bacteria in order to make water potable according to Environmental Protection Agency (EPA) guidelines. Hydrous hybrid Fe–Ca–Zr oxide nanoadsorbent presented a marked fluoride adsorption capacity of 250 mg/g at pH 7.0 (±0.1) much greater than other commercially accessible adsorbents for both synthetic and real water samples. The adsorption isotherms, Freundlich and Dubinin–Radushkevich (D–R) fitted reasonably well fine having high coefficient of regression values. The adsorption of fluoride was established well using pseudo-second-order kinetics. The fluoride loaded adsorbent was efficiently regenerated by using an alkali solution. Interestingly, the developed nanomaterial not only showed excellent fluoride removal capacity but also demonstrated good antibacterial activity against Escherichia coli with IC 50 (25 μg/mL). [ABSTRACT FROM AUTHOR]

For the past few decades, biosorption has been widely investigated for the removal of different contaminants in aqueous media. A number of biomasses of different genre have been identified to possess good biosorption capacity. Insights into biosorption mechanisms have been provided by various researchers in order to develop a fundamental scientific understanding of the biosorption process. However, biosorption has not been employed widely for its large-scale commercial applications. The key factors that affect the growth and evolution of biosorption as a practical technology for decontamination of wastewaters include, (1) lack of investigations on multi-component solutions and wastewaters with complex matrix effects, (2) incomplete understanding of physico-chemical characteristics of biomasses of different types, (3) lack of studies to improve the performance of biosorbents through surface functionalization, and (4) non-integration of biosorption in wastewater/water treatment plants. This critical review aims to identify and discuss the practical limitations of biosorption and provide future research directions to make biosorption a technologically viable process with emphasis on selection and modification of biomasses to suit desired treatment applications, identify appropriate operation modes for large-scale applications of biosorption, and perform techno-economic evaluation of overall biosorption processes. [ABSTRACT FROM AUTHOR]

Solid phase extraction performed with commercial polymer beads to treat soil contaminated by chlorophenols (4-chlorophenol, 2,4-dichlorophenol and pentachlorophenol) as single compounds and in a mixture has been investigated in this study. Soil-water-polymer partition tests were conducted to determine the relative affinities of single compounds in soil-water and polymer-water pairs. Subsequent soil extraction tests were performed with Hytrel 8206, the polymer showing the highest affinity for the tested chlorophenols. Factors that were examined were polymer type, moisture content, and contamination level. Increased moisture content (up to 100%) improved the extraction efficiency for all three compounds. Extraction tests at this upper level of moisture content showed removal efficiencies ≥70% for all the compounds and their ternary mixture, for 24 h of contact time, which is in contrast to the weeks and months, normally required for conventional ex situ remediation processes. A dynamic model characterizing the rate and extent of decontamination was also formulated, calibrated and validated with the experimental data. The proposed model, based on the simplified approach of “lumped parameters” for the mass transfer coefficients, provided very good predictions of the experimental data for the absorptive removal of contaminants from soil at different individual solute levels. Parameters evaluated from calibration by fitting of single compound data, have been successfully applied to predict mixture data, with differences between experimental and predicted data in all cases being ≤3%. [ABSTRACT FROM AUTHOR]

The current nanotechnological advancements provide an astonishing insight to fabricate nanomaterials for nano-bioremediation purposes. Exciting characteristics possessed by hybrid matrices at the nanoscale knock endless opportunities to nano-remediate environmentally-related pollunanomaterials tants of emerging concern. Nanometals are considered among the oldest generation of the world has ever noticed. These tiny nanometals and nanometal oxides showed enormous potential in almost every extent of industrial and biotechnological domains, including their potential multipurpose approach to deal with water impurities. In this manuscript, we discussed their role in the diversity of water treatment technologies used to remove bacteria, viruses, heavy metals, pesticides, and organic impurities, providing an ample perspective on their recent advances in terms of their characteristics, attachment strategies, performance, and their scale-up challenges. Finally, we tried to explore their futuristic contribution to nano-remediate environmentally-related pollutants of emerging concern aiming to collect treated yet safe water that can be reused for multipurpose. • Metallic nanoparticles coupled nanohybrid matrices for water decontamination. • Highly requisite characteristics for robust materials are discussed. • Nano-bioremediation aspects of toxic elements and pesticides are given. • Scale up challenges are summarized at each level with suitable examples. [ABSTRACT FROM AUTHOR]

The significant increase in illegal use of the synthetic opioid fentanyl is leading to unintentional overdose fatalities. Spills of fentanyl where it is abused or prepared for illegal distribution can result in persistent contamination of areas. Remediation can be attempted through physical removal but may benefit greatly from application of decontamination solutions that provide in-situ degradation of fentanyl. This work investigates the efficacy of decontamination technologies for degradation of fentanyl-HCl on indoor surfaces. Decontamination studies were conducted to evaluate the oxidative degradation of fentanyl based on percarbonate, hydrogen peroxide, peracetic acid, and chlorine (bleach) chemistries. This study utilized an experimental design relevant to field operations to provide direct information to first or hazardous materials responders and providers of environmental fentanyl remediation services, who may otherwise rely on unverified approaches. Across a range of nonporous indoor surfaces, results suggest that water (with or without detergent) spraying alone can physically remove 70–90% of fentanyl (with all fentanyl recovered in runoff). In nearly all cases, the spray application of peracetic acid or acetified bleach oxidants resulted in statistically significant degradation of fentanyl (>95% reduction), with noticeably lower efficacy for other oxidants (e.g., pH neutral bleach and OxiClean™). The decontamination efficacy was significantly reduced upon the addition of cutting agents that competed for oxidant demand. [Display omitted] • Fentanyl contaminated properties are increasing without proper guidance for cleanup. • Decontamination solutions were assessed on the ability to degrade fentanyl. • High efficacies were measured leading to significant degradation of fentanyl. • Benign additives can significantly impact the expected efficacy of a cleanup product. • More research is needed to evaluate effects of decontamination methods in the field. [ABSTRACT FROM AUTHOR]

Abstract: Cold atmospheric gas plasma treatment (CAP) is an alternative approach for the decontamination of fresh and minimally processed food. In this study, the effects of growth phase, growth temperature and chemical treatment regime on the inactivation of Salmonella enterica serovar Typhimurium (S. Typhimurium) by Nitrogen CAP were examined. Furthermore, the efficacy of CAP treatment for decontaminating lettuce and strawberry surfaces and potato tissue inoculated with S. Typhimurium was evaluated. It was found that the rate of inactivation of S. Typhimurium was independent of the growth phase, growth temperature and chemical treatment regime. Under optimal conditions, a 2 min treatment resulted in a 2.71 log-reduction of S. Typhimurium viability on membrane filters whereas a 15 min treatment was necessary to achieve 2.72, 1.76 and 0.94 log-reductions of viability on lettuce, strawberry and potato, respectively. We suggest that the differing efficiency of CAP treatment on the inactivation of S. Typhimurium on these different types of fresh foods is a consequence of their surface features. Scanning electron microscopy of the surface structures of contaminated samples of lettuce, strawberry and potato revealed topographical features whereby S. Typhimurium cells could be protected from the active species generated by plasma. [Copyright &y& Elsevier]

Abstract: Graphene oxide (GO) is a highly effective absorbent of methylene blue (MB) and can be used to remove MB from aqueous solution. A huge absorption capacity of 714mg/g is observed. At initial MB concentrations lower than 250mg/L, the removal efficiency is higher than 99% and the solution can be decolorized to nearly colorless. The removal process is fast and more efficient at lower temperatures and higher pH values. The increase of ionic strength and the presence of dissolved organic matter would further enhance the removal process when MB concentration is high. The results indicate that GO can be applied in treating industrial effluent and contaminated natural water. The implications to graphene-based environmental technologies are discussed. [Copyright &y& Elsevier]

Abstract: Various chemical compounds are currently under review for final approval as poultry decontaminants in the European Union (EU). Concentration is among the factors considered by the EU authorities in the evaluation of these treatments. The aim of this research was to compare the growth parameters for pathogenic and spoilage bacteria in presence of high and low concentrations of poultry decontaminants to assess whether such treatments could involve a potential sanitary risk for consumers. Growth curves for Salmonella enterica serotype Enteritidis, Listeria monocytogenes, Pseudomonas fluorescens and Brochothrix thermosphacta were obtained at different levels of trisodium phosphate (TSP; 1.74%; 0.58%), acidified sodium chlorite (ASC; 210ppm; 70ppm) and citric acid (CA; 0.27%; 0.09%). The modified Gompertz equation was used as primary model to fit observed data. ASC and TSP were the most effective compounds in increasing lag phase (L) and reducing maximum growth rate (μ) in Gram-negative bacteria. Gram-positive bacteria were more influenced by CA. At high TSP levels, μ for Salmonella decreased. Low TSP levels increased μ for Salmonella and Listeria relative to control samples. In presence of 0.27% CA, Brochothrix showed the highest L and the lowest μ among strains tested. These results suggest that low TSP and high CA concentrations could favour the outgrowth of pathogenic bacteria (e.g. Salmonella) relative to spoilage bacteria, rending these treatments potentially dangerous for consumers. The findings of this study may be useful to the EU authorities and meat processors in their efforts to select adequate treatments for control of bacteria on poultry. [Copyright &y& Elsevier]

The present investigation was designed to remove ibuprofen from aqueous solutions and wastewater by activating hydrogen peroxide using ultrasonication (US)/ultraviolet (UV) radiation/zeolite-titanium. The physical-chemical properties of the photocatalyst were determined using BET, FTIR, XRD, FESEM, and EDX-mapping techniques. The titanium oxide crystal size and the catalyst BET were determined to be 4.97 nm and 39.88 m2/g, respectively. Tests were performed in a reactor (with a volume of 316 mL) located in an ultrasonic bath to intensify reactions. The synergistic impact of the components of the UV/US/H 2 O 2 /Photocatalyst system was explored. The maximum efficiency (99.58%) was obtained at H 2 O 2 concentration of 0.05 mM, pH 5, UV power of 6 W, photo-catalyst dose of 1 g/L, and contact time of 100 min. The pH variable was more effective than the other parameters. Ions of NO 3 −, Cl−, and SO 4 2− had a slightly negative effect on contaminant removal efficiency. The ibuprofen removal (based on COD) from urban water and hospital wastewater was attained 77.82% and 66.24%, respectively. The ibuprofen removal by the developed system followed the first-order kinetic. The results show that the system has high efficiency and reasonable costs (with treatment cost of 6.25 €/m3) for ibuprofen decontamination. • The crystalline zeolite-TiO 2 catalyst with a suitable BET (39.88 m2/g) was produced. • Ibuprofen was removed from water and wastewater using UV/ultrasonic/H 2 O 2 /catalyst. • Ibuprofen was removed 99% at pH 5, 0.05 mM H 2 O 2 , and 1 g/L catalyst. • The electrical energy for the studied process was calculated to be 29.1 kW h/m3. [ABSTRACT FROM AUTHOR]

Destruction of polychlorinated biphenyls (PCBs) in contaminated soils and wastes using circulating fluidized bed combustion (CFBC) technology was studied using a pilot plant and simulated waste material. The results show that the technology is effective and particularly promising for treatment of PCB-containing materials like the toxic sludge from a large contaminated site. Destruction of the toxics in the gas phase appears to be very fast, and over 99.9999% destruction and removal efficiency can be achieved in the temperature range 875–880°C. Heat transfer in the fluidized bed also appears adequate. Toxic residues in treated soil can be reduced to very low levels. Rate-controlling factors of the decontamination process are analyzed, and key issues for determination of the process conditions are discussed. [Copyright &y& Elsevier]

Abstract: Four commercially available antibacterial products (two wipes and two sprays) were tested under laboratory conditions on a range of food contact surfaces (wood, glass, plastic, Microban® incorporated plastic). The products’ effectiveness at preventing cross-contamination of Escherichia coli and Staphylococcus aureus and the influence of surface type and drying time were assessed. Survival of the bacterial culture (approximately 400 colonies per 8cm2) on the above preparation surfaces was determined using an in situ nitroblue tetrazolium (NBT) method. In the absence of any antibacterial products, both bacteria survived up to 120min on all test surfaces with glass and plastic showing no reduction in bacterial number. The order of survival is: glass>plastic⪢Microban® incorporated plastic>wood (<8%). The length of drying time did not affect the survival of either bacterium on glass and plastic surfaces. On wood and Microban® incorporated plastic, E. coli appeared to be more sensitive to drying time than S. aureus. Only plastic appeared to affect the effectiveness of the antibacterial products, where the reduction in bacterial number was significantly lower than the other test surfaces (). The overall results suggest the antibacterial products are effective in disinfecting food preparing surfaces, provided products instructions are carefully followed. [Copyright &y& Elsevier]

Acid-adapted cultures of Escherichia coli O157:H7 and Listeria monocytogenes were inoculated in meat decontamination spray-washing runoff fluids in order to evaluate their survival and potential to form biofilms on stainless steel coupons. The cultures (107 cfu ml−1) and stainless steel coupons were exposed to mixtures of water and organic acid washings (composites of each of 2% acetic acid or lactic acid washings with water washings from meat decontamination in proportions of 1/9, 1/49, 1/99 [vol/vol]) or to water washings for up to 14 days at 15°C. E. coli O157:H7 formed biofilms and remained detectable (&ges;1.3 log cfu cm−2) on stainless steel for up to 4 d in the 1/9 dilution (pH 3.17–3.77) of the organic acid washings, and persisted throughout storage (14 d) in the 1/49 (pH 3.96–4.33) and 1/99 (pH 4.34–6.86) dilution of the organic acid washings. L. monocytogenes populations were unable to form detectable (<1.3 log cfu cm−2) biofilms in the 1/9 and 1/49 dilutions of both organic acid washings for up to 14 d; however, by day-14 in the 1/99 dilution of the washings, the pathogen was able to attach at detectable levels (2.7 to 3.4 logs). The pH effects of lower concentrations (1/49 or 1/99) of acidic washings decreased over time due to the formation of amine compounds produced by the natural meat flora, allowing resuscitation of the acid-stressed pathogen survivors. The resuscitation of acid-stressed pathogens may potentially enhance their survival and prevalence in biofilms and thus more attention should be focused on avoiding or minimizing the collection of decontamination runoff fluids on food contact equipment surfaces. [Copyright &y& Elsevier]

In this study ion binding to solid organic matter was investigated. We used the NICA–Donnan model to describe the interaction between Cu(II), Pb(II), and Cd(II) ions and a lignocellulosic substrate extracted from wheat bran. Such a material represents a very cheap and flexible substrate, which can be used as a natural filter to remove toxic metal ions from industrial effluents or applied in the decontamination and rehabilitation of abandoned industrial sites. Moreover, such a material also represents a very simple model of natural organic matter derived from lignin and cellulose, for which there is now a lack of thermodynamic data as far as their interaction with toxic metal ions is concerned. Experimental results were obtained in various conditions of pH and ionic strength. In our modeling, we used the acidity constants and the concentration of sites that were determined in a previous work. The parameters deduced from the NICA–Donnan model were also compared to thermodynamic data available for other cases of natural organic matter, mainly humic substances. [Copyright &y& Elsevier]

Eight contaminants were used to perform a surrogate contamination test to evaluate safety of the process for producing recycled pulp for adult paper diapers. We performed a safety evaluation of the recycling process for producing recycled pulp following the European Food Safety Authority safety assessment for polyethylene terephthalate (PET) bottles using recycled PET. We also compared the first tier safety limit established on the basis of TTC (C limit) in the pulp that contained recycled pulp with residual contaminant concentrations (C res). If C limit > C res, there is no concern regarding safety of the recycling process. C limit was determined to be 0.46 mg/kg-pulp based on the human exposure threshold of 0.15 μg/person/day using the scenario in which a bedridden senior citizen uses four adult paper diapers manufactured with pulp containing 10% recycled pulp per day. C res was derived from the initial concentration in used pulp (0.17 mg/kg-pulp), and decontamination rate was obtained from the surrogate contamination test. The C res of the eight contaminants were between 0.0017 and 0.10 mg/kg-pulp, which were all below the C limit of 0.46 mg/kg-pulp. These results indicated there was no safety problem regarding this process for producing recycled pulp for adult paper diapers. • A safety evaluation of the process was performed for producing recycled pulp. • The contamination by unexpected chemicals must be considered when recycling. • A surrogate contamination test was performed using eight contaminants. • The evaluation followed the EFSA safety assessment for recycled PET. • Our results indicated there was no safety problem regarding this process. [ABSTRACT FROM AUTHOR]

Firefighter uniforms protect firefighters from exposure to potentially harmful chemicals including a range of semi-volatile organic compounds (SVOCs). Contaminated uniforms can become a secondary source of firefighters' exposure to these chemicals. There is inconsistency on the removal efficiency of SVOCs during the cleaning, laundering and field decontamination of firefighting uniforms. Therefore, this study aims to assess how effective decontamination and laundering processes are in reducing firefighter uniforms as a vector for transport and exposure to SVOCs. Firefighters who had attended a controlled house fire and simulated container burns had their uniforms sampled pre- and post-laundering. Clean station wear was laundered with contaminated uniforms and after a load of contaminated uniforms to assess inter and intra load contamination. Surface wipes were collected from uniforms across 12 fire stations, after they had returned from a laundering provider. Concentrations of 13 polycyclic aromatic hydrocarbons (PAHs), six organophosphate flame retardants (OPFRs) and seven polybrominated diphenyl ethers (PBDEs) were measured in the collected samples. The concentrations of ∑ 13 PAHs in firefighters uniforms ranged between 0.063 and 43 μg g−1, while concentration of ∑ 6 OPFRs were between 0.061 and 90 μg g−1 with ∑ 7 PBDEs concentrations being measured between 0.00054 and 0.97 μg g−1.The highest concentrations of ∑ 13 PAHs were measured on the outer layers of gloves at an average of 19 μg g−1, with the highest ∑ 6 OPFRs concentrations being measured in the middle layers of gloves at an average of 31 μg g−1. The highest ∑ 7 PBDEs concentrations were measured on the shell layers of turnout jackets at 0.42 μg g−1. The significant reduction in ∑ 13 PAHs after laundering or decontamination was only found in 3 of the 16 sampled areas from firefighting uniforms. No significant differences were found in the between pre- and post-laundering concentrations of ∑ 6 OPFRs or ∑ 7 PBDEs in firefighting uniforms. The current laundering techniques do not appear to effectively remove PAHs, OPFRs and PBDEs at the measured concentrations from firefighters' uniforms. Further research is required to assess if chemical exposure though firefighting uniforms poses a health risk to firefighters and to develop methods for the removal of SVOCs from firefighting uniforms. • Current washing and water-only field decontamination techniques do not effectively remove SVOCs from firefighters' uniforms. • Contamination of washing machines and cross-contamination of laundry can occur when washing firefighting uniforms. • Chemical diffusion from firefighting uniforms may contribute to the air and dust concentration of SVOCs in fire stations. [ABSTRACT FROM AUTHOR]

Pre-harvest sanitization of irrigation water has potential for reducing pathogen contamination of fresh produce. We compared the sanitizing effects of irrigation water containing neutral electrolyzed oxidizing water (EOW) or sodium hypochlorite (NaClO) on pre-harvest lettuce and baby spinach leaves artificially contaminated with a mixture of Escherichia coli , Salmonella Enteritidis and Listeria innocua (~1 × 108 colony-forming units/mL each resuspended in water containing 100 mg/L dissolved organic carbon, simulating a splash-back scenario from contaminated soil/manure). The microbial load and leaf quality were assessed over 7 days, and post-harvest shelf life evaluated for 10 days. Irrigation with water containing EOW or NaClO at 50 mg/L free chlorine significantly reduced the inoculated bacterial load by ≥ 1.5 log 10 , whereas tap water irrigation reduced the inoculated bacterial load by an average of 0.5 log 10 , when compared with untreated leaves. There were no visual effects of EOW or tap water irrigation on baby spinach or lettuce leaf surfaces pre- or post-harvest, whereas there were obvious negative effects of NaClO irrigation on leaf appearance for both plants, including severe necrotic zones and yellowing/browning of leaves. Therefore, EOW could serve as a viable alternative to chemical-based sanitizers for pre-harvest disinfection of minimally processed vegetables. • Electrolyzed oxidizing water (EOW) was used for pre-harvest produce sanitation. • Artificially-contaminated manure suspension was inoculated onto lettuce and spinach. • Irrigation with EOW-treated water at 50 mg/L of free chlorine reduced bacterial load. • EOW-treated water had no negative effects on leaf quality pre- and post-harvest. • In comparison, sodium hypochlorite irrigation showed leaf necrosis and browning. [ABSTRACT FROM AUTHOR]

This study evaluated the application of a Halobacteriovorax isolated from water of the Adriatic Sea (Italy) in controlling V. parahaemolyticus in mussels (Mytilus galloprovincialis). Two 72 h laboratory-scale V. parahaemolyticus decontamination experiments of mussels were performed. The test microcosm of experiment 1 was prepared using predator/prey free mussels experimentally contaminated with Halobacteriovorax / V. parahaemolyticus at a ratio of 103 PFU/105 CFU per ml, while that of experiment 2 using mussels naturally harbouring Halobacteriovorax that were experimentally contaminated with 105 CFU per ml of V. parahaemolyticus. For experiment 1, was also tested a control microcosm only contaminated with 105 CFU per ml of V. parahaemolyticus.. Double layer agar plating and pour plate techniques were used to enumerate Halobacteriovorax and V. parahaemolyticus , respectively. 16 S rRNA analysis was used to identify Halobacteriovorax. For both experiments in the test microcosm the concentration of prey remained at the same level as that experimentally added, i.e. 5 log for the entire analysis period. In experiment 1, V. parahaemolyticus counts in mussels were significantly lower in the test microcosm than the control with the maximum difference of 2.2 log at 24 h. Results demonstrate that Halobacteriovorax can modulate V. parahaemolyticus level in the mussels. The public impact of V. parahaemolyticus in bivalves is relevant and current decontamination processes are not always effective. Halobacteriovorax is a suitable candidate in the development of a biological approach to the purification of V. parahaemolyticus in mussels. • parahaemolytivcus control in mussels by Halobacteriovorax was studied. • Halobacteriovorax controlled the growth of V. parahaemolyticus in mussels. • Halobacteriovorax could integrate conventional approach for mussel depuration. [ABSTRACT FROM AUTHOR]

Highlights: [•] Energy effective pathways for the removal of organic water pollutants are described. [•] Reevesite decolorized selected dyes within 15min of visible light irradiation. [•] Phenols were degraded with additional H2O2 in approximately 3h. [•] The photocatalyst becomes unstable at low pH. [ABSTRACT FROM AUTHOR]

Abstract: Polymerase chain reaction (PCR) is widely used to detect specific DNA sequences for purposes of microbial identification, clinical diagnosis, and basic research. The most pernicious problem plaguing this technique is contamination of PCR reagents with previously amplified material. We propose a useful tool for PCR reagent purification from contaminating nucleic acid using DEAE–cellulose and present the analysis of this technique for both decontamination efficiency and an effect on the reagent activity. We also show the suitability of the proposed approach for decontamination of the Taq polymerase, monoclonal antibodies to Taq polymerase, and Moloney murine leukemia virus (M-MLV) reverse transcriptase. [Copyright &y& Elsevier]

As an emerging class of silica-based mesoporous materials with incorporation of active components (e.g., transition metals/metal oxides and nanocarbons), SBA-15-based composites (X@SBA-15) have been attracting increasing attention in the field of water treatment owing to their unique characteristics and excellent remediation performance. This paper reviews recent advances in catalytic applications of X@SBA-15 to remove organic contaminants from water. Emphasis is made on the use of X@SBA-15 in four advanced oxidation processes (AOPs) (i.e., photocatalysis, Fenton-like oxidation, catalytic ozonation, and sulfate radical-based oxidation). Impregnation and hydrothermal methods are two most widely used synthetic approaches to combine the active composites with SBA-15, obtaining a synergistic effect with significant improvement in their individual catalytic activity for pollution remediation. The enhanced generation of highly reactive hydroxyl radicals from the surface of X@SBA-15 was widely recognized as being responsible for water decontamination using these AOPs, while sulfate radicals were also involved during activation of persulfate or peroxymonosulfate. Especially, X@SBA-15 could significantly enhance the light harvest and reduce the recombination of photo-induced electrons and holes during photocatalytic treatment, which also played the critical role in oxidizing the organics. The superior catalytic performance of X@SBA-15 without leaching metal ions during successive runs demonstrated the excellent reusability and structural stability. Together with the reduced toxicity of the treated solutions and the cost-effective characteristics of X@SBA-15 nanohybrids reported in the published literature, their great potential as the efficient and environmentally friendly heterogeneous catalysts in a real use scenario is suggested. Finally, the future perspectives on the development and practical utilization of X@SBA-15 are addressed. • Recent applications of X@SBA-15 for catalytic water decontamination are first reviewed. • Impregnation and hydrothermal methods are used to prepare X@SBA-15 with synergistic catalysis. • X@SBA-15 showed excellent catalytic performance in advanced oxidation processes with reduced ecotoxicity. • Hydroxyl radicals and/or sulfate radicals are involved in catalytic AOPs by X@SBA-15. • Green X@SBA-15 catalysts can be reused for sustainable water purification with high stability. [ABSTRACT FROM AUTHOR]

Atmospheric cold plasma (ACP) is an effective method for microbiological decontamination. This study evaluated an alternative water-based decontamination approach for inactivation of bacterial population from fresh produce and in the wash water generated from fresh produce washing. The study characterised ACP inactivation of attached Listeria innocua and Pseudomonas fluorescens inoculated on lettuce in comparison to chlorine treatment. P. fluorescens was sensitive to ACP treatment and was reduced below detection limit within 3 min of treatment. L. innocua population was reduced by ∼2.4 Log 10 CFU/g after 5 min of treatment; showing similar inactivation efficacy to chlorine treatment. The microbial load in wash water was continuously decreased and was below detection limits after 10 min of ACP treatment. Micro-bubbling along with agitation assisted the bacterial detachment and distribution of reactive species, thus increasing bacterial inactivation efficacy from fresh produce and wash water. A shift in pH of plasma functionalised water was observed along with high concentration of nitrate and ozone with a relative amount of nitrites which increased with plasma exposure time. Further, L. innocua treated at different independent pH conditions showed minimal or no effect of pH on ACP bacterial inactivation efficacy. Aqueous ACP treatment poses a promising alternative for decontamination of fresh produce and the associated wash-waters which could be applied in the food industry to replace continuous chlorine dosing of process waters. • Aqueous ACP significantly reduced Listeria sp by up to 4.18 Log 10 CFU/g. • The microbial load in lettuce wash water was continuously decreased. • Short lived reactive species were important for this bacterial inactivation process. • Minimal or no effect of pH on ACP bacterial inactivation efficacy. • Submerged cold plasma process enables recycling of wash water without continuous chemical dosage. [ABSTRACT FROM AUTHOR]