Gamma radiation/H2O2 treatment of a nonylphenol ethoxylates: Degradation, cytotoxicity, and mutagenicity evaluation

Ecotoxicology Evaluation of a Fenton-Type Process Catalyzed with Lamellar Structures Impregnated with Fe or Cu for the Removal of Amoxicillin and Glyphosate

Antibiotics and pesticides, as well as various emerging contaminants that are present in surface waters, raise significant environmental concerns. Advanced oxidation processes, which are employed to eliminate these substances, have demonstrated remarkable effectiveness. However, during the degradation process, by-products that are not completely mineralized are generated, posing a substantial risk to aquatic ecosystem organisms; therefore, it is crucial to assess effluent ecotoxicity following treatment. This study aimed to assess the toxicity of effluents produced during the removal of amoxicillin and glyphosate with a Fenton-type process using a laminar structure catalyzed with iron (Fe) and copper (Cu). The evaluation included the use of Daphnia magna, Selenastrum capricornutum, and Lactuca sativa, and mutagenicity testing was performed using strains TA98 and TA100 of Salmonella typhimurium. Both treated and untreated effluents exhibited inhibitory effects on root growth in L. sativa, even at low concentrations ranging from 1% to 10% v/v. Similarly, negative impacts on the growth of algal cells of S. capricornutum were observed at concentrations as low as 0.025% v/v, particularly in cases involving amoxicillin-copper (Cu) and glyphosate with copper (Cu) and iron (Fe). Notably, in the case of D. magna, mortality was noticeable even at concentrations of 10% v/v. Additionally, the treatment of amoxicillin with double-layer hydroxides of Fe and Cu resulted in mutagenicity (IM ≥ 2.0), highlighting the necessity to treat the effluent further from the advanced oxidation process to reduce ecological risks.

Cationic distributions and dielectric properties of magnesium ferrites fabricated by sol-gel route and photocatalytic activity evaluation

Sol-gel auto combustion method was adopted to fabricate magnesium ferrite (MgFe2O4) nanoparticles. The structural and morphological properties was studied by XRD, FTIR, and SEM analysis. The average particle sizes of MgFe2O4 was in the range of 35–55 nm. The octahedral & Tetrahedral bond lengths, R AE (tetrahedral edge length), R BE (shared octahedral edge length) and R BEU (individual octahedral edge length), cationic radii (tetra and octa-sites) were also determined. The magnetic strength also showed direct reliance on bond angle and indirect to bond length. Hoping length L a and L b and bond angles are also measured. The frequency dependent conductivity and dielectric properties of MgFe2O4 were investigated by Impedance analyzer. The photocatalytic activity (PCA) is appraised against MB (methylene blue) dye and MgFe2O4 calcined at 800 °C showed promising degradation (78%) under visible light irradiation. The findings revealed that MgFe2O4 is can harvest the solar light, which could be employed for the remediation of wastewater contains textile dyes.

Plant mediated magnetic nano composite as promising scavenger's radionuclides for the efficient remediation in aqueous medium

The present investigation demonstrates the environment friendly plant mediated green synthesis of magnetic bio composite nanoparticles by the chemical co-precipitation of magnetite phase from aqueous medium. Water contaminated with uranium is one of the most serious environmental issues. This study aims to overcome this issue by effectively adsorbing uranium from water at a pH range of 7. Several studies have recently been published throughout the world that demonstrates uranium adsorption from water, although they have all been conducted in acidic media with pH less than 6. This work addressed that issue, and maximal adsorption was achieved at pH 7 using a synthetic magnetic bio composites sorbent derived from tree bark (Amla). The magnetic bio composites were characterized by FTIR, XRD, FE-SEM, and EDX. The computations of the XRD data indicated that magnetic bio composites have nano composite with an average diameter of around 12.1 nm. This has an adsorption capacity of 121.95 mg g^-1. The correlation regression (r²) coefficients obtained for the various isotherm models indicate that the sorption process conformed to the Langmuir and Temkin models. Thermodynamic studies revealed that the sorption process onto plant mediated magnetic bio material is endothermic and spontaneous, which is significant for reuse and recovery of adsorbed material. A desorption test was also performed to regenerate the material by removing the adsorbed uranium (VI) by HCL with an 84.3% success rate.

Green Synthesis and Characterization of Cobalt Oxide Nanoparticles Using Psidium guajava Leaves Extracts and Their Photocatalytic and Biological Activities

The advanced technology for synthesizing nanoparticles utilizes natural resources in an environmentally friendly manner. Additionally, green synthesis is preferred to chemical and physical synthesis because it takes less time and effort. The green synthesis of cobalt oxide nanoparticles has recently risen due to its physico-chemical properties. In this study, many functional groups present in Psidium guajava leaf extracts are used to stabilize the synthesis of cobalt oxide nanoparticles. The biosynthesized cobalt oxide nanoparticles were investigated using UV-visible spectroscopic analysis. Additionally, Fourier-transform infrared spectroscopy revealed the presence of carboxylic acids, hydroxyl groups, aromatic amines, alcohols and phenolic groups. The X-ray diffraction analysis showed various peaks ranging from 32.35 to 67.35°, and the highest intensity showed at 36.69°. The particle size ranged from 26 to 40 nm and confirmed the average particle size is 30.9 nm. The green synthesized P. guajava cobalt oxide nanoparticles contain cobalt as the major abundant element, with 42.26 wt% and 18.75 at% confirmed by the EDAX techniques. SEM images of green synthesized P. guajava cobalt oxide nanoparticles showed agglomerated and non-uniform spherical particles. The anti-bacterial activity of green synthesized P. guajava cobalt oxide nanoparticles was evaluated against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli with a 7 to 18 mm inhibitory zone. The photocatalytic activity was evaluated using green synthesized P. guajava cobalt oxide nanoparticles and observed 79% of dye degradation. The MTT assay of P. guajava cobalt oxide nanoparticles showed an excellent cytotoxic effect against MCF 7 and HCT 116 cells compared to normal cells. The percentage of cell viability of P. guajava cobalt oxide nanoparticles was observed as 90, 83, 77, 68, 61, 58 and 52% for MCF-7 cells and 82, 70, 63, 51, 43, 40, and 37% for HCT 116 cells at the concentration of 1.53, 3.06, 6.12, 12.24, 24.48, 50, and 100 μg/mL compared to control cells. These results confirmed that green synthesized P. guajava cobalt oxide nanoparticles have a potential photocatalytic and anti-bacterial activity and also reduced cell viability against MCF-7 breast cancer and HCT 116 colorectal cancer cells.

Advanced oxidation processes: Performance, advantages, and scale-up of emerging technologies

Advanced oxidation processes (AOPs) are promising technologies for partial or complete mineralization of contaminants of emerging concern by highly reactive hydroxyl, hydroperoxyl, superoxide, and sulphate radicals. Detailed investigations and reviews have been reported for conventional AOP systems that have been installed in full-scale wastewater treatment plants. However, recent efforts have focused on the peroxymonosulphate, persulphate, catalytic ozonation, ultrasonication and hydrodynamic cavitation, gamma radiation, electrochemical oxidation, modified Fenton, and plasma-assisted AOPs. This critical review presents the detailed mechanisms of emerging AOP technologies, their performance for treatment of contaminants of emerging concern, the relative advantages and disadvantages of each technology, and the remaining challenges to scale-up and implementation. Among the evaluated technologies, the modified electrochemical oxidation, gamma radiation, and plasma-assisted systems demonstrated the greatest potential for successful and sustainable implementation in wastewater treatment due to their environmental safety, compatibility, and efficient transformation of contaminants of emerging concern by a variety of reactive species. The other emerging AOP systems were also promising, but additional scale-up trials and a deeper understanding of their reaction kinetics in complex wastewater matrices are necessary to determine the technical and economic feasibility of full-scale processes.

Distribution patterns and transportation behavior of alkylphenol polyethoxylate degradation metabolites among river, port area, and coastal water bodies of Kaohsiung City, Taiwan

In this study, we conducted a comprehensive study of the distribution, transportation behavior and potential ecological risk of alkylphenol polyethoxylates (APnEOs) in the aquatic environments of Kaohsiung City, Taiwan because little information is available regarding the fate of APnEOs in the water bodies of a total environment. At Love River, APnEOs concentrations were much higher at upstream of interception stations L15 (27.33 ± 1.22 μg/L) and L16 (6.31 ± 0.14 μg/L) than at downstream of interception stations L1-L14 (0.69-2.54 μg/L). Additionally, the average ethoxy (EO) chain lengths of APnEOs at L15 and L16 were longer than at L1-L14. These observations were attributed to the sluice between L14 and L15 that intercepts and accumulates untreated sewage from upstream areas and to the infrastructure of the sewage system that prevents domestic sewage from flowing downstream in the river and to the Kaohsiung Port Area. At Kaohsiung Port Area, APnEO concentrations ranging from 0.63 to 6.50 μg/L were measured. The concentration range and average EO chain length of these APnEOs were similar to those of the downstream stretch of the river, which was attributed to the mixing efficiency of the Kaohsiung Port Area and Love River through tidal exchange. At Cijin Coastal Area, APnEO concentrations ranged from 0.14 to 18.77 μg/L. Notably, the APnEO concentration of surface waters was much higher than that of bottom waters. This observation was attributed to the sewage discharged from the ocean outfall buoying up to the surface instead of mixing with surrounding bottom waters. In potential ecological risk, 19 of 39 sampling points exceeded toxic equivalency of 1 μg/L, and approximately 48.7% of the sampling points would exceed the threshold. The result provides insight into the environmental implications of APnEOs contamination in aquatic environments and useful information for environmental policy and ecological risk assessments.

Degradation of Reactive Yellow 18 Using Ionizing Radiation Based Advanced Oxidation Processes: Cytotoxicity, Mutagenicity and By-Product Distribution

The degradation of Reactive Yellow 18 (RY-18), induced by gamma radiation in aqueous medium, was carried out as a function of gamma radiation dose (5–20 kGy) and concentration of hydrogen peroxide, the initial dye concentration and pH of the solution were optimized for the maximum degradation efficiency. Gamma radiations alone and in combination with H2O2 were used to degrade the RY-18. A degradation rate of 99% was achieved using an absorbed dose of 20 kGy, 0.6 mL H2O2 in acidic pH. Variations in the functional groups of untreated and treated RY-18 were determined by FTIR analysis. The LCMS technique was used to determine the intermediates formed during the degradation process. The cytotoxicity and mutagenicity of RY-18 were studied by hemolytic and Ames tests, respectively. There were significant reductions in cytotoxicity and mutagenicity in response to gamma radiation treatment. Cytotoxicity was reduced from 15.1% to 7.6% after treatment with a 20 kGy absorbed dose of gamma radiations with 0.6 mL H2O2. Mutagenicity was reduced by 81.3% and 82.3% against the bacterial strains TA98 and TA100 after treatment with a 20 kGy absorbed dose with 0.6 mL H2O2. The advanced oxidation process efficiency was evaluated using the byproduct formations, which were low-molecular-weight organic acid units, which through further oxidation were converted into carbon dioxide and water end products. Based on RY-18 degradation, cytotoxicity and mutagenicity reduction, the gamma radiation in combination with H2O2 has potential for the removal of dye from the effluents.

SnO2/UV/H2O2 and TiO2/UV/H2O2 Efficiency for the Degradation of Reactive Yellow 160A: By-Product Distribution, Cytotoxicity and Mutagenicity Evaluation

Advanced oxidation processes (AOPs) have emerged as a promising approach for the removal of organic dyes from effluents. Different AOPs were employed for the degradation of Reactive Yellow 160A (RY-160A) dye, i.e., SnO2/UV/H2O2 and TiO2/UV/H2O2. In the case of UV treatment, maximum degradation of 28% was observed, while UV/H2O2 furnished 77.78% degradation, and UV/H2O2/TiO2 degraded the RY-160A dye up to 90.40% (RY-160A 30 mg/L, 0.8 mL of H2O2). The dye degradation was 82.66% in the case of UV/H2O2/SnO2 at pH 3. FTIR and LC-MS analyses were performed in order to monitor the degradation by-products. The cytotoxicity and mutagenicity of RY-160A dye were evaluated by hemolytic and Ames (TA98 and TA100 strains) assays. It was observed that the RY-160A dye solution was toxic before treatment, and toxicity was reduced significantly after treatment. Results indicated that UV/H2O2/TiO2 is more efficient at degrading RY-160A versus other AOPs, which have potential application for the remediation of dyes in textile effluents.

Enhanced Solar Photocatalytic Activity of Thermally Stable I:ZnO/Glass Beads for Reduction of Cr(VI) in Tannery Effluent

Chromium (VI) in tannery effluent is one of the major environmental concerns for the environmentalists due to the hazardous nature of Cr(VI) ions. To reduce Cr(VI) to Cr(III) as an innocuous moiety, pure and I-doped ZnO was grafted over the etched surface of glass beads by successive ionic layer adsorption and reaction (SILAR). Powdered, pure, and I-doped ZnO scrapped from the surface of glass beads was characterized for crystallinity, morphology, and elemental composition by XRD, SEM, TEM, and EDX. The optical properties of both photocatalysts revealed that owing to optimized iodine doping of ZnO, reduction in the bandgap was observed from 3.3 to 2.9 eV. The crystalline nano-bricks of I:ZnO adhered to glass beads were investigated to have remarkable capability to harvest sunlight in comparison to intrinsic ZnO nanodiscs. The thermal stability of I:ZnO was also found to be much improved due to doping of ZnO. The photocatalytic activities of ZnO/GB and I:ZnO/GB were compared by extent of reduction of Cr(VI) under direct natural sunlight (600–650 KWh/m2). The disappearance of absorbance peaks associated with Cr(VI) after treatment with I:ZnO/GB confirmed higher photocatalytic activity of I:ZnO/GB. The reaction parameters of solar photocatalytic reduction, i.e., initial pH (5–9), initial concentration of Cr(VI) (10–50 ppm), and solar irradiation time (1–5 h) were optimized using response surface methodology. The solar photocatalytic reduction of Cr(VI) to Cr(III) present in real tannery effluent was examined to be 87 and 98%, respectively, by employing ZnO/GB and I:ZnO/GB as solar photocatalysts. The extent of reduction was also confirmed by complexation of Cr(VI) and Cr(III) present in treated and untreated tannery waste with 1, 5-diphenylcarbazide. The results of AAS and UV/vis spectroscopy for the decrease in concentration of Cr also supported the evidence of higher efficiency of I:ZnO/GB for reduction of Cr(VI) in tannery effluent. Reusability of the fabricated photocatalyst was assessed for eight cycles, and magnificent extent of reduction of Cr(VI) indicated its high efficiency. Conclusively, I:ZnO/GB is a potential and cost-effective candidate for Cr(VI) reduction in tannery effluent under natural sunlight.

UVA/persulfate-driven nonylphenol polyethoxylate degradation: effect of process conditions

UV/persulfate (UV/PS) technologies have gained increased attention as efficient alternatives for removing pollutants from different classes, although processes based on the UVA-driven S2O82- (PS) activation have not yet been discussed in the literature for the removal of the nonionic surfactant nonylphenol polyethoxylate (NPEO). The present study investigated the simultaneous effect of the initial persulfate concentration ([PS]₀) and specific photon emission rate (E_P,0) on NPEO degradation by UVA/PS following a Doehlert experimental design. The results for [NPEO]₀ = (4.65 ± 0.15) mg L^-1 indicated more than 97.8% NPEO removal after 2 h, with pseudo first-order specific degradation rate (k_obs) of 0.0320 min^-1, for [PS]₀ = 7.75 mmol L^-1 and E_P,0 = 0.437 μmol photons L^-1 s^-1. Under these conditions, NPEO half-life time was about 22 min, and the EC₅₀-48 h (% v/v) values for Daphnia similis before and after treatment did not differ significantly. Higher values of E_P,0 would influence NPEO removal for [PS]₀ not higher than 8-10 mmol L^-1, although lower degradation efficiencies were obtained with higher [NPEO]₀ or real wastewater, except for longer reaction times. Additionally, UVA/PS showed to be efficient for tensoactivity removal, despite the negligible total organic carbon (TOC) removal achieved. Finally, UVC and UVA resulted in NPEO degradation higher than 96% and similar tensoactivity removals when UVA/PS was conducted under optimal conditions ([PS]₀ = 10 mmol L^-1; E_P,0 = 0.324 μmol photons L^-1 s^-1), suggesting that UVA radiation available in solar light could be advantageously employed for NPEO removal at concentrations usually found in wastewater.

Electrocoagulation induced treatment of indigo carmine textile dye in an aqueous medium: the effect of process variables on efficiency evaluated using biochemical response of Gammarus pulex

Indigo carmine removal from aqueous solutions was investigated by the electrocoagulation process and biochemical responses of Gammarus pulex to solutions before and after treatment were studied. Electrocoagulation experiments in the first stage were carried out with central composite design (CCD) using response surface methodology (RSM). Optimization of process variables that maximize indigo carmine removal by electrocoagulation process was carried out by using a second-order model within the studied test range of various process variables. According to the optimization results, optimum conditions for obtaining 82.55% maximum indigo carmine removal were pH 5.86, a current density of 13.31 mA/cm², an indigo carmine concentration of 20.01 mg/L, and a time period of 115.80 min. Under optimum conditions for indigo carmine removal, the amount of sludge formed was 0.928 kg/m³, electrode consumption was 0.0305 kg/m³, and energy consumption was 7.461 kWh/m³. The operating cost was calculated as 0.79 US$/m³ under treatment conditions where optimum indigo carmine removal was achieved. In the second stage, G. pulex was exposed to treated and untreated synthetic indigo carmine solutions obtained from experiments according to optimum conditions in order to investigate the biochemical response for 24 and 96 h. Treatment efficiency was evaluated with superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), and cytochrome P450 1A1 (CYP1A1) biomarkers. Results clearly showed that the electrocoagulation process was a simple and effective treatment method for the decolorization of wastewaters containing indigo carmine dye. The bioassays used in the present study provided good credibility for checking the detoxification of treated and untreated indigo carmine solutions.

Treatment of pharmaceutical wastewater by ionizing radiation: Removal of antibiotics, antimicrobial resistance genes and antimicrobial activity

In present study, the treatment of real pharmaceutical wastewater from an erythromycin (ERY) production factory by gamma irradiation was investigated. Results showed that a variety of antimicrobial resistance genes (ARGs), involving MLSB, tet, bla, multidrug, sul, MGEs and van genes and plentiful 9 bacterial phyla were identified in the raw wastewater. In addition to ERY, sulfamethoxazole (SMX) and tetracycline (TC) were also identified with the concentration of 3 order of magnitude lower than ERY. Results showed that the abatement of ARGs and antibiotics was much higher than that of antimicrobial activity and COD. With the absorbed dose of 50 kGy, the removal percentage of ARGs, ERY, antimicrobial activity and COD was 96.5-99.8%, 90.0%, 47.8% and 10.3%, respectively. The culturable bacteria were abated fast and completely at 5.0 kGy during gamma irradiation. The genus Pseudomonas was predominant in raw wastewater (56.7%) and its relative abundance decreased after gamma irradiation, to 1.3% at 50 kGy. With addition of peroxymonosulfate (PMS, 50 mM), the antimicrobial activity disappeared completely and ERY removal reached as high as 99.2% at the lower absorbed dose of 25 kGy. Ionizing radiation-coupled technique is a potential option to treat pharmaceutical wastewater for reduction of antibiotics, ARGs and antimicrobial activity.

Protective role of fat hen (Chenopodium album L.) extract and gamma irradiation treatments against fusarium root rot disease in sunflower plants

One of the most drastic diseases causing economic losses in sunflower crops is fusarium root rot caused by Fusarium solani. Plant extracts and ionizing radiation provide alternative environmentally safe control agents that have a significant role in controlling and overcoming this fungal plant pathogen. In the present study, the effect of different concentrations of aqueous Chenopodium album extract (2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0, 5.5 and 6.0%) and gamma radiation at a dose of 6 Gy were examined for their efficacy in inducing resistance of sunflower plants against fusarium root rot caused by F. solani MG-3 by evaluation of some physiological and biochemical parameters of infected and healthy plants under greenhouse conditions. The pre-treatment of sunflower seeds with 6% C. album extract and 6 Gy gamma radiation reduced fusarium incidence from 47.49% to 28.25%. Also, nucleic acid content, ascorbic acid, α-tocopherol, anthocyanin, total flavonoids, proline, glycine betaine and lipid components significantly increased in irradiated infected plants treated with C. album extract, while H₂ O₂ content and lipid peroxidation markedly decreased as compared with healthy control plants. Moreover, treatment with gamma radiation reduced the amount of unsaturated fatty acids through accumulation of saturated fatty acids compared with non-irradiated plants; treatment with C. album extract also enhanced the content of unsaturated fatty acids, with a noticeable decrease in saturated fatty acid content. Hence, C. album extract and gamma radiation can be used to enhance biological control of fusarium root rot of sunflower plants.

Biological Treatment of Real Textile Effluent Using Aspergillus flavus and Fusarium oxysporium and Their Consortium along with the Evaluation of Their Phytotoxicity

Twenty-one fungal strains were isolated from dye-contaminated soil; out of them, two fungal strains A2 and G2-1 showed the highest decolorization capacity for real textile effluent and were, hence, identified as Aspergillus flavus and Fusarium oxysporium based on morphological and molecular methods. The highest decolorization percentage of 78.12 ± 2.1% was attained in the biotreatment with fungal consortium followed by A. flavus and F. oxysporium separately with removal percentages of 54.68 ± 1.2% and 52.41 ± 1.0%, respectively. Additionally, ultraviolet-visible spectroscopy of the treated effluent showed that a maximum peak (λ_max) of 415 nm was reduced as compared with the control. The indicators of wastewater treatment efficacy, namely total dissolved solids, total suspended solids, conductivity, biological oxygen demand, and chemical oxygen demand with removal percentages of 78.2, 78.4, 58.2, 78.1, and 77.6%, respectively, demonstrated a considerable decrease in values due to fungal consortium treatment. The reduction in peak and mass area along with the appearance of new peaks in GC-MS confirms a successful biodegradation process. The toxicity of treated textile effluents on the seed germination of Vicia faba was decreased as compared with the control. The shoot length after irrigation with effluents treated by the fungal consortium was 15.12 ± 1.01 cm as compared with that treated by tap-water, which was 17.8 ± 0.7 cm. Finally, we recommended the decrease of excessive uses of synthetic dyes and utilized biological approaches for the treatment of real textile effluents to reuse in irrigation of uneaten plants especially with water scarcity worldwide.

Degradation of moxifloxacin by ionizing radiation and toxicity assessment

The gamma ray induced degradation of moxifloxacin in aqueous media has been evaluated. The drug solutions (50 & 100 mg/L) were irradiated to absorbed doses of 0.3, 0.6, 0.9, 1.2, 1.5, 2, 3 and 4 kGy using Cs-137 gamma radiation source. The parameters such as drug initial concentration, oxidant (H2O2) concentration and gamma ray absorbed doses were optimized. The efficiency of Advanced oxidation processes (AOP) was evaluated on the basis of degradation, reduction in chemical oxygen demand (COD) and toxicity reduction of the drug. The maximum degradation of 94.01 and 88.30% was achieved when drug solutions were exposed to gamma irradiation absorbed dose of 4 kGy which enhanced to 100 and 99.06% in the presence of H2O2 (0.5 mL/L) for 50 and 100 mg/L respectively. A significant reduction in COD 72 and 75% for 50 mg/L while 65 and 69% in case of 100 mg/L was noted using gamma and gamma/H2O2 respectively at absorbed dose of 4 kGy. The parameters such as dose constant (k), removal efficiency (G-value), gamma ray absorbed doses required for 50, 90 and 99% degradation (D 0.50, D 0.90 and D 0.99) have been calculated. The radiolytic degradation was monitored by UV–Vis spectrophotometer and HPLC, FT-IR studies were performed to investigate the change in functional groups before and after treatment, while GC-MS analysis was carried out to monitor intermediates/degraded end-products. The FT-IR spectra has shown complete destruction of aromatic rings after radiation treatment but a minor peak appeared at 1216 cm−1 corresponding to CO stretching. The GC-MS study for the drug samples treated with gamma/H2O2 has shown no any significant peak which confirms the complete degradation. The cytotoxicity of treated samples was carried out by hemolytic assay and mutagenicity using Ames test before and after each treatment. The hemolytic test showed 73.92% hemolysis, while gamma/H2O2 treatment reduced the mutagenicity to 74.08 and 65.66% against TA98 and TA100 bacterial strains respectively. The response surface methodology (RSM) was employed to optimize the data. The obtained data elaborate that gamma/H2O2process is promising approach for the remediation of pharmaceutical waste effluent.

Gamma and UV radiations induced treatment of anti-cancer methotrexate drug in aqueous medium: Effect of process variables on radiation efficiency evaluated using bioassays

This studystudy focuses on the effect of radiation treatment and hydrogen peroxide (H₂O₂) on the toxicity of anticancer methotrexate. For cytotoxicity, different bioassays such as Allium cepa, hemolytic, brine shrimp were employed. The Ames test was used for mutagenicity analysis. The solutions having concentrations 5, 10 and 15 ppm were irradiated with UV radiation exposure time 15, 30, 45, 60, 75 and 90 min and gamma radiation absorbed doses 0.3, 0.6, 0.9, 1.2, 2, 3 and 4 kGy in combination with with H₂O₂. There was a clear difference observed for aqueous solution before and after treatment with reference to cytotoxicity and mutagenicity. In Allium cepa test, a 47.07, 44.36 and 38.23% increase in root length (RL), root count (RC) and mitotic index (MI) was observed, respectively, for UV/H₂O₂ treatment and in the case of gamma/H₂O₂ treatment, the RL, RC and MI were increased up to 49.39, 52.63 and 52.38%, respectively. Brine shrimp test has shown 85.95 and 91.30% decrease in toxicity using UV/H₂O₂ and gamma/H₂O₂ respectively, while hemolytic test has shown 19.21 and 26.32% hemolysis using UV/H₂O₂ and gamma/H₂O₂, respectively. The mutagenicity reduced up to 82.3, 86.46 and 89.59% (TA98) and 85.42, 87.5 and 90.63% (TA100) for UV/H₂O₂ while 89.59, 90.63 and 93.75% (TA98) and 84.38, 89.59 and 92.71% (TA100) for gamma/H₂O₂. The UV and gamma radiation along with H₂O₂ based AOPs are promising approaches to detoxify the wastewater which can be extended to real hospital liquid effluent effectively.

Toxicity evaluation of hospital laundry wastewaters treated by microbial fuel cells and constructed wetlands

Hospital laundries generate high wastewater volumes with the presence of several contaminants. Nevertheless, few studies have investigated the toxicity of these effluents and looked for treatment alternatives that might reduce this eventual toxicity. So, the present study assessed the performance of an integrated system combining a microbial fuel cell (MBFC) and a constructed wetland (CW) to reduce toxic effects of wastewaters generated at a hospital laundry. After collection, raw effluents remained 7 days at the first unit (MBFC) of integrated system. Afterward, they were transferred to the second unit (CW) unit where remained more 7 days totaling a hydraulic detention time of 14 days. The toxicity evaluation involved three different organisms: Daphnia magna (acute ecotoxicity), Lactuca sativa (phytotoxicity) and Allium cepa (phytotoxicity, cytotoxicity, mutagenicity, and genotoxicity). Got results revealed an extremely acute ecotoxicity against D. magna, high phytotoxic effects in the L. sativa and A. cepa assays, and genotoxicity in the A. cepa assay for the untreated effluents. Furthermore, no significant incidence of micronuclei was observed in the raw wastewaters. Regarding the treatment, after the first stage, it was possible to verify that MBFC reduced the toxicity of the wastewaters only in some tested assays (endpoints) while after the CW (second stage) the effluents presented a complete absence of toxicity of the investigated bioassays. Therefore, the use of the integrated system combining two environmentally friendly technologies can be considered promising, since both MBFC and CW presented a complimentary effect with excellent results regarding the reduction of the overall toxicity of hospital laundry wastewaters.

Functional categories of microbial toxicity resulting from three advanced oxidation process treatments during management and disposal of contaminated water

Large volumes of contaminated water are produced via intentional and unintentional incidents, including terrorist attacks, natural disasters and accidental spills. Contaminated waters could contain harmful chemicals, which present management and disposal challenges. This study investigates three Advanced Oxidation Processes (AOPs) - UV/H₂O₂, O₃/H₂O₂, and electrochemical oxidation using a boron-doped diamond (BDD) anode - to treat eleven contaminants including herbicides, pesticides, pharmaceuticals, and flame retardant compounds. To address treatment and toxicity concerns, this study focuses on the resulting microbial toxicity via Microtox® toxicity and Nitrification Inhibition tests. The results suggest four functional Microtox® toxicity categories upon AOP treatment, which are useful for streamlining AOP selection for specific applications. Except for one compound, the O₃/H₂O₂ and UV/H₂O₂ AOPs achieved, within experimental error, 100% parent compound degradation during 2 h of treatment for all contaminants, as well as Microtox® toxicities that declined below 10% by the end of the treatment. In addition, anodic oxidation with a BDD electrode exhibited slower degradation and some increases in Microtox® toxicity. Only one compound exhibited above 50% Nitrification Inhibition, indicating the robustness of activated sludge to many contaminated and AOP-treated waters. These results indicate that AOP pre-treatment can be a viable strategy to facilitate drain disposal of contaminated waters, but that eco-toxicity may remain a concern.

Kinetic Study of Degradation of Basic Turquise Blue X-GB and Basic Blue X-GRRL using Advanced Oxidation Process

This study focuses on application of advanced oxidation (Photo-Fenton) processes to decolorize Basic Turquise Blue (BTB) X-GB 250% and Basic Blue (BB) X-GRRL 250% dyes. The percent decolorization was studied in terms of effect of variation in intensity of UV light at optimum conditions of all the parameters (pH = 3.0, H2O2 = 4.8 mM, FeSO4 = 1.6 mM, temperature = 50 °C, time = 80 min for BTB X-GB, and pH = 5.0, H2O2 = 5.6 mM, FeSO4 = 2.0 mM, temperature = 40 °C, time = 60 min for BB X-GRRL). Maximum decolorization was obtained at maximum intensity (15660 counts/min) of UV light as 96.17% for BTB X-GB and 88.48% for BB X-GRRL. First order, 2nd order and BMG kinetic models were used to analyze the data obtained for intensity of UV light. BMG model gives us the higher values of correlation coefficients for all data of both the dyes. The results have shown that Photo-Fenton oxidation process is the beneficial and effective for oxidation treatment of waste water effluents containing dyes as main pollutants.

Mesoporous TiO2/carbon catalytic ozonation for degradation of p-chloronitrobenzene

In this study, a mesoporous TiO₂/carbon catalyst (TiO₂/C) was prepared by a facile impregnation-carbonization approach to catalyze ozonation of p-chloronitrobenzene (p-CNB). The catalyst was well characterized and the catalytic efficiency under various conditions was systematically evaluated. TiO₂/C has a disordered mesostructure with a high specific surface area. 92.8% of p-CNB (2 μmol/L) can be degraded within 20 min in the TiO₂/C/O₃ system in the presence of 1 mg/L O₃, 100 mg/L catalyst, at pH = 5. Based on the evaluation of the effect of basic parameters, it could be deduced that the removal of p-CNB relied on the synthetic effect of catalysis by TiO₂/C and the autocatalytic induction of p-CNB. The removal efficiency of p-CNB, the structure change and the leaching of Ti ions were also evaluated in five cycles, indicating TiO₂/C is stable and recyclable for catalytic ozonation in water treatment.

Comparative toxicity study of a novel non-ionic surfactant, vanillin ethoxylates, and nonylphenol ethoxylates in Chinese hamster ovary cells in vitro

Surfactants such as alkylphenol polyethoxylates (APEOs) and nonylphenol ethoxylates (NPEOs) are commonly used worldwide, but the majority of these compounds, together with their metabolites, have been reported to induce severe biological toxicity. Here, we evaluated for the first time the cytotoxicity, genotoxicity and mitochondrial damage in Chinese hamster ovary (CHO-K1) cells caused by a novel non-ionic surfactant, vanillin ethoxylates (VAEOs), an alternative to APEOs. In parallel, the same in vitro bioassays were conducted on NPEOs along with their metabolic byproducts 4-nonylphenol (4-NP) and vanillin. The results showed that the cytotoxic potency order was NPEOs > 4-NP > VAEOs>vanillin using CCK-8 assays. Also, 4-NP showed potential direct DNA damage in SOS/umu tests, whereas NPEOs, VAEOs and vanillin showed no positive result with and without S9 addition. In addition, none of the test compounds showed obvious genotoxic effects with low olive tail moment value using comet assays. However, all test compounds were shown to cause mitochondrial impairment by increasing mitochondrial mass and decreasing mitochondrial membrane potential in a concentration-dependent manner. And further analysis of reactive oxygen species (ROS) and mitochondrial superoxide (MNSOD) measurement showed that mitochondrial impairment was induced by oxidative stress with intracellular ROS and MNSOD overproduction. It's worth noting that VAEOs and vanillin cause relative lower cytotoxic, genotoxic and mitochondrial damage effects than NPEOs and 4-NP, indicating that VAEOs have the potential to substitute NPEOs as suitable surfactants. Take together, this study elucidates the toxicity profiles of VAEOs and NPEOs relatively comprehensively, and further toxicity analyses are suggested in the population, community and ecosystem.

Metallurgical Processing Strategies for Metals Recovery from Industrial Slags

Slag produced as a byproduct in industrial processes, contains considerable metals contents, which need to be recovered to avoid environmental contamination. In present review, the types, applications, recovery of metals from slag and their hazardous effects have been discussed. Gravimetric, magnetic, floatation, pyrometallurgical and hydrometallurgical treatments are discussed for processing of charge chrome, steel, copper smelter, brass smelter, tin, incineration, ferrochrome and silico-manganese slags for the extraction of various metal ions (Mg, Cu, Zn, Pb, Cd, Ni, Co, Mn, Fe, As, Cr, Al, Nb, Ag, Au, Nb, Ta, Cu, Co, Ni, Fe, V, Cr). The possibility of biometallurgical processing of slags is also evaluated. Merits and demerits of extraction and purification techniques are highlighted with possible suggestions and possibility of integrated leaching techniques is also discussed.

Sol–Gel Synthesis of Mesoporous Silica–Iron Composite: Kinetics, Equilibrium and Thermodynamics Studies for the Adsorption of Turquoise-Blue X-GB Dye

Mesoporous silica (MPS) and MPS-Fe composite was prepared via sol–gel technique and characterized by BET, FTIR, XRD, SEM and pZc. The MPS and MPS-Fe adsorption efficiencies were evaluated for a cationic dye Turquoise-blue X-GB. The MPS-Fe composite showed pore size and BET values of 9.52 nm and 309 m2/g, respectively. XRD and SEM analysis revealed the amorphous nature and uniform distribution of spherical partciles with average particle size of 50 nm of MPS-Fe composite. The points of zero (pZc) charge found to be 2.3 and 6.3 for MPS and MPS-Fe, respectively. The MPS and MPS-Fe showed promising efficiency for the adsorption of Turquoise-blue X-GB as a function of medium pH, contact time, dye initial concentration and temperature. Among, Freundlich, Langmuir, Harkins–Jura, Temkin, Doubinin–Radushkevich isotherms, the Turquoise-blue X-GB followed Langmuir isothermal model with adsorption capacities of 83.34 mg/g and 74.07 mg/g for MPS and MPS-Fe composite, respectively. Among kinetics models, pseudo second order kinetic model fitted to the dye adsorption with R2 values of 0.998 and 0.988 for MPS and MPS-Fe composite, respectively. The negative values of enthalpy (ΔH) and free energy (ΔG) revealed exothermic and spontaneous adsorption of dye at room temperature. Results revealed that MPS and MPS-Fe composite have promising potential for Turquoise-blue X-GB dye adsorption and could possibly be extended for the adsorption of dyes from textile effluents.

Degradation of 4-nonylphenol in marine sediments by persulfate over magnetically modified biochars

In this study, an environmentally friendly and economically viable bamboo biochar (BB) was modified by Fe₃O₄ and was applied for the treatment of real river sediments containing the endocrine disruptor chemical (EDC) 4-nonylphenol (4-NP). The microporosity of Fe₃O₄-BB was clearly observed from the N₂ adsorption isotherms. The catalytic performance of Fe₃O₄-BB is highly dependent on pH and the catalyst dosage. The degradation efficiency of 4-NP (85%) was achieved at pH 3.0 using an initial dosage of 3.33 g L^-1 Fe₃O₄-BB and 2.3 × 10^-5 M persulfate (PS) in a biochar-sediment system. The kinetic behavior of 4-NP degradation with catalysis can be accounted by using the Langmuir-Hinshelwood type kinetic model. The MTT assay results indicated that Fe₃O₄-BB has a low potent cytotoxic effect and is therefore suitable for application in remediation of contaminated sediment.

Gamma Radiation and Hydrogen Peroxide Based Advanced Oxidation Process for the Degradation of Disperse Dye in Aqueous Medium

In view of promising efficiency of advanced oxidation process (AOP), gamma radiation in combination with H2O2 was employed for the degradation of disperse red 73 (DR73) dye. Cs-137 gamma radiation source was used for dye aqueous solution irradiation. The process variables such as pH (3–9), H2O2 concentration (0.3–0.9 mL), gamma radiation absorbed dose (1–20 kGy) and DR73 initial concentration (50–150 mg/L) were optimized for maximum degradation of dye. The efficiency of AOP was evaluated on the basis of dye degradation, water quality parameters and toxicity reduction. Degradation of DR73 was achieved 69% using gamma radiation absorbed dose of 20 kGy and at the same dose 96.3% degradation was achieved in the presence of 0.9 mL/L H2O2. The dye degradation found to be dependent on dye initial concentration and pH of the medium. The radiolytic progress of DR73 was monitored by Fourier transform infrared (FTIR) and UV-Visible spectroscopy. The chemical oxygen demand (COD) and biological oxygen demand (BOD) were reduced significantly in response of treatment of dye at optimum conditions of process variables. The toxicity of treated and un-treated dye solution was monitored by haemolytic and Ames assays. Results revealed that the toxicity of DR73 dye was also reduced significantly after treatment. Findings revealed that the gamma radiation based AOPs are promising and could possibly be used for the remediation of textile wastewater contains toxic dyes.

ZnO/UV/H2O2 Based Advanced Oxidation of Disperse Red Dye

In view of promising efficiency of advanced oxidation process, ZnO/UV/H2O2 based advanced oxidation process (AOP) was employed for the degradation of Disperse Red-60 (DR-60) in aqueous medium. The process variables such as concentration of catalysts, reaction time, pH, dye initial concentration and H2O2 dose were evaluated for maximum degradation of dye. The maximum degradation of 97% was achieved at optimum conditions of H2O2 (0.9 mL/L), ZnO (0.6 g/L) at pH 9.0 in 60 min irradiation time. The analysis of treated dye solution revealed the complete degradation under the effect of ZnO/UV/H2O2 treatment. The water quality parameters were also studied of treated and un-treated dye solution and up to 79% COD and 60% BOD reductions were achieved when dye was treated with at optimum conditions. The dissolved oxygen increased up to 85.6% after UV/H2O2/ZnO treatment. The toxicity was also monitored using hemolytic and Ames tests and results revealed that toxicity (cytotoxicity and mutagenicity) was also reduced significantly. In view of promising efficiency of UV/H2O2/ZnO system, it could possibly be used for the treatment of wastewater containing toxic dyes.

UV/H2O2/Ferrioxalate Based Integrated Approach to Decolorize and Mineralize Reactive Blue Dye: Optimization Through Response Surface Methodology

The decolorization and mineralization of Reactive Blue 222 dye was studied using UV/H2O2/ferrioxalate approach in combination with Pleorotus ostreatus. The dye was decolorized by UV/H2O2/ferrioxalate based advanced oxidation process (AOP) at different levels of process variables dye concentration, catalyst dose, pH, reaction time and resultantly, 80% decolorization was achieved. Pleorotus ostreatus treatment enhanced the dye degradation up to 92% at optimum levels of pH, temperature, inoculum size, carbon and nitrogen sources at specific concentration. Response Surface Methodology (RSM) was employed for optimization under face-centered central composite design (CCD). Although both treatments were found efficient for the removal of dye, but on applying the integrated approach, 96% dye removal was obtained which led to complete degradation of the dye. FTIR analysis confirmed the degradation of dye into low mass compounds. The water quality assurance parameters were measured to assess the mineralization efficiency. A significant reduction in COD (94%) and TOC (92%) were found when dye was degraded integrated approach. A phytotoxicity analysis on Pisum sativum plant revealed the non-toxic behavior of metabolites produced. Results revealed that the integrated approach is highly promising for the decolorization and mineralization of the Reactive Blue 222 dye and is also extendable to treat the dye in textile wastewater.

4-Nonylphenol effects on rat testis and sertoli cells determined by spectrochemical techniques coupled with chemometric analysis

Herein, vibrational spectroscopy has been applied for qualitative identification of biomolecular alterations that occur in cells and tissues following chemical treatment. Towards this end, we combined attenuated total reflection Fourier-transform infrared (ATR-FTIR) and Raman spectroscopy to assess testicular toxicology after 4-nonylphenol (NP) exposure, an estrogenic endocrine disruptor affecting testicular function in rats and other species. Rats aged 21, 35 or 50 days received NP at intra-peritoneal doses of 0, 25, 50 or 100 mg/kg for 20 consecutive days. Primary Sertoli cells (SCs) were treated with NP at various concentrations (0, 2.5, 5, 10 or 20 μM) for 12 h. Post-exposure, testicular cells, interstitial tissue and SCs were interrogated respectively using spectrochemical techniques coupled with multivariate analysis. Distinct biomolecular segregation between the NP-exposed samples vs. control were observed based on infrared (IR) spectral regions of 3200-2800 cm^-1 and 1800-900 cm^-1, and the Raman spectral region of 1800-900 cm^-1. For in vivo experiments, the main wavenumbers responsible for segregation varied significantly among the three age classes. The main IR and Raman band differences between NP-exposed and control groups were observed for Amide (proteins), lipids and DNA/RNA. An interesting finding was that the peptide aggregation level, Amide Ӏ-to-Amide II ratio, and phosphate-to-carbohydrate ratio were considerably reduced in ex vivo NP-exposed testicular cells or SCs in vitro. This study demonstrates that ATR-FTIR and Raman spectroscopy techniques can be applied towards analysing NP-induced testicular biomolecular alterations.

Structural, Dielectric and Magnetic Studies of Perovskite [Gd1−xMxCrO3 (M = La, Co, Bi)] Nanoparticles: Photocatalytic Degradation of Dyes

Nanoparticles (NPs) of Gd1−xMxCrO3 (M = La, Co, Bi) were synthesized by microemulsion techniques, involving simultaneous single ion substitution philosophy. Structural, magnetic, dielectric properties, morphology, elemental analysis and distribution size of fabricated nano-crystalline were determined. The techniques employed for investigation are X-ray diffraction (XRD), vibrating sample magnetometer (VSM), dielectric measurement and scanning electron microscopy (SEM), energy dispersive X-ray (EDX), photoluminescence (PL) and atomic force microscopy (AFM), respectively. XRD pattern confirm that all the as-synthesized NPs have orthorhombic structure and successfully substituted of different metal ions into the regular crystal structure of GdCrO3. The lattice parameters X-ray density, bulk density, porosity and grain size were calculated from XRD pattern of Gd1−xMxCrO3 (M = La, Co, Bi) substituted and un-substituted GdCrO3. The magnetic hysteresis loop of fabricated product confirmed that the entire sample exhibits ferromagnetic behavior at room temperature. It was also found that the fabricated NPs show excellent photocatalytic activity (PCA) against Congo-red, about 78.24% after 55 min of incubation.

Lead Remediation Using Smart Materials. A Review

The nanoparticles have been prepared and employed as excellent adsorbents for the sequestration of heavy metal ions and hazardous impurities from the aqueous media. The surface morphological, textural and structural properties of nanoparticles have been modified, which are capable and potentially useful for the remediation of metal ions. Several metals (oxides, doped, nanocomposites of Fe, Ti, Zn, SiO2, SiC, Mo, Co, Ni, Zr, Mn, Si, S, Al, Cu, Ce, graphene, CNTs) were reported an efficient adsorbents for the removal of lead (Pb) ions from aqueous media and polluted water. The present review focuses on different kinds of nanoparticles such as metal oxides, carbon based and host supported employed for removal of Pb ions under varying experimental conditions such as pH, temperature, contact time and concentrations. The preparation strategies, physicochemical properties and adsorption are also discussed. Based on studies, it was found that the smart materials are affective adsorbents for the purification of wastewater containing Pb ions and could possibly extended for the remediation of other heavy metal ions.