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Pollution
1990
Harrison, R. M. (Roy M)
Much has happened in the pollution field since 1982 when the first edition of this work was written. This edition includes new subject areas such as radioactive pollution and chemistry and pollution of the stratosphere.
Mostrar más [+] Menos [-]Pollution prevention
1992
Theodore, Louis | McGuinn, Young C.
Food pollution
1972
Marine, Gene | Van Allen, Judith
Adsorptive removal of propranolol under fixed-bed column using magnetic tyre char: Effects of wastewater effluent organic matter and ball milling Texto completo
2022
Feizi, Farzaneh | Sarmah, Ajit K. | Rangsivek, Ropru | Gobindlal, Kapish
We investigated the competitive effects of different fractions of wastewater treatment plant effluent organic matter (EfOM) on adsorption of an organic micro pollutant (OMP), propranolol (PRO), in a fixed bed column packed with magnetic tyre char (MTC). The results showed that the presence of EfOM inhibited PRO adsorption in wastewater leading to decreased PRO adsorption capacity from 5.86 to 2.03 mg/g due to competitive effects and pore blockage by smaller EfOM fractions. Characterization of EfOM using size exclusion chromatography (LC-OCD) showed that the principal factor controlling EfOM adsorption was pore size distribution. Low molecular weight neutrals had the highest adsorption onto MTC while humic substances were the least interfering fraction. Effect of important parameters such as contact time, linear velocity and bed height/diameter ratio on MTC performance was studied in large-lab scale columns. Linear velocity and contact time were found to be effective in increasing adsorption capacity of PRO on MTC and delaying breakthrough time. Increase in linear velocity from 0.64 cm/min to 1.29 cm/min increased mass transfer and dispersion, resulting in considerable rise of adsorbed amount (5.86 mg/g to 22.58 mg/g) and increase in breakthrough time (15.8–62.7 h). Efficiency of non-equilibrium Hydrus model considering dispersion and mass transfer mechanism was demonstrated for real wastewater and scale up purposes. Ball milling for degradation of adsorbed PRO and regeneration of MTC resulted in 79% degradation of PRO was achieved after 5 h milling (550 rpm), while the addition of quartz sand increased the efficiency to 92%.
Mostrar más [+] Menos [-]Arsenic accumulation in rice: Alternative irrigation regimes produce rice safe from arsenic contamination Texto completo
2022
Rokonuzzaman, MD. | Ye, Zh | Wu, C. | Li, Wc
The natural occurrence of arsenic (As) in groundwater & soils and its bioaccumulation in rice grains is a major health concern worldwide. To combat the problem, best combination of irrigation management and suitable rice variety altering As content in grains must be ensured. With this aim, a field trial was conducted with two rice varieties and water management including alternate wetting and drying (AWD) and continuous flooding (CF) irrigation regimes with As contaminated groundwater (AsW) and temporarily stored groundwater (TSG) and river water for only CF (as control). Results revealed that As content in different portions of paddy plant was significantly different (P < 0.001) with irrigation practices and rice varieties. AWD irrigation with TSG accumulated lower As in rice grains compared with CF-AsW for both varieties. Data showed that AWD-TSG practice led to 61.37% and 60.34% grain As reduction for BRRI dhan28 and BRRI dhan29, respectively, compared with CF-AsW. For Principle Component Analysis (PCA), first principle component (PC1) explained 91.7% of the variability and irrigation water As, soil total and available As, straw As, root As and husk As were the dominating parameters. With significant (P < 0.05) variation in yields between the genotypes, AWD increased grain yield by 29.25% in BRRI dhan29 Compared with CF. However, translocation factor (TF) and bioconcentration factor (BCF) for both varieties were less than one for all the treatments. The addition of this study to our knowledge base is that, AWD-TSG with BRRI dhan29 can be an As–safe practice without compromising yields.
Mostrar más [+] Menos [-]Activation of peroxydisulfate by ball-milled α-FeOOH/biochar composite for phenol removal: Component contribution and internal mechanisms Texto completo
2022
Zhao, Ling | Zhang, Hui | Zhao, Beibei | Lyu, Honghong
Persulfate-based advanced oxidation process is considered as a promising technology for the degradation of phenol, where efficient, cost effective, and green methods with high peroxydisulfate (PS) activation capacity is of increasing demand. In this work, an in-situ liquid phase precipitation combined with ball milling method was applied for the synthesized of α-FeOOH/biochar, as be the PS activator for phenol degradation. Results showed that the ball-milled α-FeOOH and red pine wood biochar prepared at 700 °C (BM-α-FeOOH/PBC700) exhibited the highest catalytic property with PS for phenol oxidation (a phenol removal rate of 100%), compared with the BM-α-FeOOH (16.0%) and BMPBC700 (66.3%). The presence of intermediate products such as hydroquinone and catechol, and total organic carbon (TOC) removal rate (88.9%) proved the oxidation of phenol in the BM-α-FeOOH/PBC700+PS system. The characterization results showed that the functional groups (e.g., CO, C–O, Fe–O, and Si–O), the dissolved organic matter (DOM) in biochar, the loading of Fe element, and higher degree of graphitization and defect structures, contributed to the activation of PS to form free radicals (i.e., SO₄·⁻, ·OH, ·O₂⁻, and hVB⁺) for phenol oxidation, of which, SO₄·⁻ and ·OH account for 72.1% of the phenol removal rate. The specific contribution to the PS activation for phenol oxidation by each part of the materials was calculated based on the “whole to part” experiment. The contribution of DOM, acid-soluble substance, and carbon matrix and basal part in BM-α-FeOOH/PBC700 were 6.0%, 40.9%, and 53.1%, respectively. The reusability experiments of BM-α-FeOOH/PBC700 demonstrated that the composite was relatively stable after four cycles of reuse. Among three co-existing anions (NO₃⁻, Cl⁻, and HCO₃⁻), HCO₃⁻ played the most significant inhibition effects on phenol removal through reducing the phenol removal rate from 89.6% to 77.9%. This work provides guidance for the design of high active and stable carbon materials that activate PS to remove phenol.
Mostrar más [+] Menos [-]Sublethal effects of metal toxicity and the measure of plant fitness in ecotoxicological experiments Texto completo
2022
Nowak, Juljan Ignacy | Faure, Nathalie | Glorieux, Cédric | Vile, Denis | Pauwels, Maxime | Frérot, Hélène
Sublethal effects of metal toxicity and the measure of plant fitness in ecotoxicological experiments Texto completo
2022
Nowak, Juljan Ignacy | Faure, Nathalie | Glorieux, Cédric | Vile, Denis | Pauwels, Maxime | Frérot, Hélène
Anthropogenic pollution is a major driver of global environmental change. To be properly addressed, the study of the impact of pollutants must consider both lethal effects and sublethal effects on individual fitness. However, measuring fitness remains challenging. In plants, the total number of seeds produced, i.e. the seed set, is traditionally considered, but is not readily accessible. Instead, performance traits related to survival, e.g., vegetative biomass and reproductive success, can be measured, but their correlation with seed set has rarely been investigated. To develop accurate estimates of seed set, relationships among 15 vegetative and reproductive traits were analyzed. For this purpose, Noccaea caerulescens (Brassicaceae), a model plant to study local adaptation to metal-contaminated environments, was used. To investigate putative variation in trait relationships, sampling included several accessions cultivated in contrasting experimental conditions. To test their applicability, selected estimates were used in the first generation of a Laboratory Natural Selection (LNS) experiment exposing experimentally plants to zinc soil pollution. Principal component analyses revealed statistical independence between vegetative and reproductive traits. Traits showing the strongest positive correlation with seed set were the number of non-aborted silicles, and the product of this number and mean silicle length. They thus appeared the most appropriate to document sublethal or fitness effects of environmental contaminants in plant ecotoxicological studies. The relevance of both estimates was confirmed by using them to assess the fitness of parental plants of the first generation of an LNS experiment: the same families consistently displayed the highest or the lowest performance values in two independent experimental metal-exposed populations. Thus, both these fitness estimates could be used to determine the expected number of offspring and the composition of successive generations in further LNS experiments investigating the impact of multi-generational exposure of a plant species to environmental pollution.
Mostrar más [+] Menos [-]Sublethal effects of metal toxicity and the measure of plant fitness in ecotoxicological experiments Texto completo
2022
Pauwels, Maxime | Frérot, Hélène | Faure, Nathalie | Vile, Denis | Laboratoire Avancé de Spectroscopie pour les Intéractions la Réactivité et l'Environnement - UMR 8516 (LASIRE) ; Institut de Chimie - CNRS Chimie (INC-CNRS)-Université de Lille-Centre National de la Recherche Scientifique (CNRS) | Évolution, Écologie et Paléontologie (Evo-Eco-Paleo) - UMR 8198 (Evo-Eco-Paléo (EEP)) ; Université de Lille-Centre National de la Recherche Scientifique (CNRS) | Écophysiologie des Plantes sous Stress environnementaux (LEPSE) ; Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Institut Agro Montpellier ; Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro) | Ecology & Biodiversity Section of the Earth & Life Institute of UCLouvain | ANR-12-JSV7-0010,ELOCANTH,Evolution de l'adaptation locale en environnement anthropisé(2012)
International audience | Highlights • Sublethal effects have to be included in ecological risk assessment. • In plants, sublethal effects on fitness can be revealed through performance traits. • Fitness, expressed as seed set, is best correlated with number and length of fruits. • Estimators for sublethal effects can be used in large-scale outdoor experiments.
Mostrar más [+] Menos [-]Health risks of phthalates: A review of immunotoxicity Texto completo
2022
Zhang, Ying | Lyu, Liang | Tao, Yue | Ju, Hanxun | Chen, Jie
Phthalates (PAEs) are known environmental endocrine disruptors that have been widely detected in several environments, and many studies have reported the immunotoxic effects of these compounds. Here, we reviewed relevant published studies, summarized the occurrence and major metabolic pathways of six typical PAEs (DMP, DEP, DBP, BBP, DEHP, and DOP) in water, soil, and the atmosphere, degradation and metabolic pathways under aerobic and anaerobic conditions, and explored the molecular mechanisms of the toxic effects of eleven PAEs (DEHP, DPP, DPrP, DHP, DEP, DBP, MBP, MBzP, BBP, DiNP, and DMP) on the immune system of different organisms at the gene, protein, and cellular levels. A comprehensive understanding of the mechanisms by which PAEs affect immune system function through regulation of immune gene expression and enzymes, increased ROS, immune signaling pathways, specific and non-specific immunosuppression, and interference with the complement system. By summarizing the effects of these compounds on typical model organisms, this review provides insights into the mechanisms by which PAEs affect the immune system, thus supplementing human immune experiments. Finally, we discuss the future direction of PAEs immunotoxicity research, thus providing a framework for the analysis of other environmental pollutants, as well as a basis for PAEs management and safe use.
Mostrar más [+] Menos [-]Antagonistic and synergistic effects of warming and microplastics on microalgae: Case study of the red tide species Prorocentrum donghaiense Texto completo
2022
Zhang, Jiazhu | Kong, Lingwei | Zhao, Yan | Lin, Qingming | Huang, Shaojie | Jin, Yafang | Ma, Zengling | Guan, Wanchun
Bibliometric network analysis has revealed that the widespread distribution of microplastics (MPs) has detrimental effects on marine organisms; however, the combined effects of MPs and climate change (e.g., warming) is not well understood. In this study, Prorocentrum donghaiense, a typical red tide species in the East China Sea, was exposed to different MP concentrations (0, 1, 5, and 10 mg L⁻¹) and temperatures (16, 22, and 28 °C) for 7 days to investigate the combined effects of MPs and simulated ocean warming by measuring different physiological parameters, such as cell growth, pigment contents (chlorophyll a and carotenoid), relative electron transfer rate (rETR), reactive oxygen species (ROS), superoxide dismutase (SOD), malondialdehyde (MDA), and adenosine triphosphate (ATP). The results demonstrated that MPs significantly decreased cell growth, pigment contents, and rETRₘₐₓ, but increased the MDA, ROS, and SOD levels for all MP treatments at low temperature (16 °C). However, high temperatures (22 and 28 °C) increased the pigment contents and rETRₘₐₓ, but decreased the SOD and MDA levels. Positive and negative effects of high temperatures (22 or 28 °C) were observed at low (1 and 5 mg L⁻¹) and high MP (10 mg L⁻¹) concentrations, respectively, indicating the antagonistic and synergistic effects of combined warming and MP pollution. These results imply that the effects of MPs on microalgae will likely not be substantial in future warming scenarios if MP concentrations are controlled at a certain level. These findings expand the current knowledge of microalgae in response to increasing MP pollution in future warming scenarios.
Mostrar más [+] Menos [-]Ultraviolet light-activated peroxymonosulfate (UV/PMS) system for humic acid mineralization: Effects of ionic matrix and feasible application in seawater reverse osmosis desalination Texto completo
2022
Alayande, Abayomi Babatunde | Hong, Seungkwan
The use of membrane-based technology has evolved into an important strategy for supplying freshwater from seawater and wastewater to overcome the problems of water scarcity around the world. However, the presence of natural organic matter (NOM), including humic substances affects the performance of the process. Here, we present a systematic report on the mineralization of humic acid (HA), as a model for NOM, in high concentration of salts using the ultraviolet light-activated peroxymonosulfate (UV/PMS) system as a potential alternative for HA elimination during membrane-based seawater desalination and water treatment processes. Effects of various parameters such as PMS concentration, solution type, pH, anions, and anion-cation matrix on HA mineralization were assessed. The results show that 100%, 78% and 58% of HA (2 mg/L TOC) were mineralized with rate constants of 0.085 min⁻¹, 0.0073 min⁻¹, and 0.0041 min⁻¹ after 180 min reaction time at pH 7 when 0.5 mM PMS was used in deionized water, sodium chloride solution (35,000 ppm) and synthetic seawater, respectively. The reduced efficiency under saline conditions was attributed to the presence of anions in the system that acted as sulfate and hydroxyl radicals’ scavengers. Furthermore, the safety of the treated synthetic seawater was evaluated by analyzing the residual transformed products. Overall, pretreatment with the UV/PMS system mitigated fouling on the RO membrane.
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