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1.
Food Chem ; 367: 130734, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34359003

RESUMEN

Isocycloseram is a new isoxazoline insecticide that can efficiently control the diamondback moth in cruciferous crops. The aim of this study was to establish a method for the determination of isocycloseram residues in/on cabbage and in the soil using HPLC-UV at 264 nm. A field test was conducted in December 2019 and 2020 to monitor isocycloseram dissipation in Jiangxi, China. Acetonitrile was used to extract isocycloseram from cabbage and soil. C18 and GCB were used to purify cabbage extracts, whereas soil extracts did not require purification. At the addition level of 0.01-1.0 mg/kg, the average recoveries in cabbage and soil were 91.81-109.95% and 89.89-104.08% respectively. After having applied 10% isocycloseram DC, isocycloseram dissipated faster in the cabbage matrix. Isocycloseram residues on cabbage leaves could be removed through simple cleaning methods, especially by soaking in 2% citric acid.


Asunto(s)
Brassica , Residuos de Plaguicidas , Contaminantes del Suelo , Cromatografía Líquida de Alta Presión , Semivida , Residuos de Plaguicidas/análisis , Suelo , Contaminantes del Suelo/análisis
2.
J Hazard Mater ; 421: 126709, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34315021

RESUMEN

Nanoscale zero-valent iron nanoparticles (nZVI) have been used for groundwater remediation and wastewater treatment due to their high reactivity, high adsorption capacity and nontoxicity. However, side reactions generally occur in tandem with the target contaminants removal process, resulting in poor electron selectivity (ES) of nZVI, and subsequently restricting its commercial application. Major efforts to increase ES of nZVI have been made in recent years. This review's objective is to provide a progress report on the significant developments in nZVI's ES during the past decade. Firstly, the definition of ES and its quantification approaches were documented, and the intrinsic (i.e. particle size, crystallinity, and surface area) and extrinsic factors (i.e. solutions pH, target contaminant concentration, and presence of co-contaminants) affecting the ES of nZVI were reported. The latest techniques for increasing ES were summarized in detail, with reference made to sulfidation, magnetization, carbon loading and other features. Then the mechanisms of those strategies for ES enhancement were described. Finally, some constructive suggestions on future research directions concerning nZVI's ES in the future were proposed.


Asunto(s)
Restauración y Remediación Ambiental , Agua Subterránea , Contaminantes Químicos del Agua , Purificación del Agua , Electrones , Hierro , Contaminantes Químicos del Agua/análisis
3.
J Hazard Mater ; 421: 126688, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34315634

RESUMEN

Improper disposal of copper mining wastes can threaten the ecosystem and human health due to the high levels of potentially toxic elements released into the environment. The objective of this study was to determine the properties of Cu mining wastes generated in the eastern Amazon and their potential risks to environment and human health. Samples of forest soil and artisanal/industrial Cu mining wastes were collected and subjected to characterization of properties and pseudo-total concentrations of Al, As, Ba, Cd, Co, Cr, Cu, Fe, Hg, Mn, Mo, Ni, Pb, and Zn, in addition to chemical fractionation of Cu. The pH ranged from near neutrality to alkaline. Pseudo-total concentrations of Cu were high in all wastes, mainly in the artisanal rock waste, with 19,034 mg kg-1, of which 61% is concentrated in the most reactive fractions. Pollution indices indicated that the wastes are highly contaminated by Cu and moderately contaminated by Cr and Ni. However, only the artisanal rock waste is associated with environmental risk. Non-carcinogenic and carcinogenic human health risks were detected, especially from exposure to Cr in the artisanal rock waste. Prevention actions and monitoring of the artisanal mining area are necessary to avoid impacts to the local population.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Cobre/toxicidad , Ecosistema , Monitoreo del Ambiente , Humanos , Residuos Industriales/análisis , Metales Pesados/análisis , Minería , Medición de Riesgo , Contaminantes del Suelo/análisis
4.
J Hazard Mater ; 421: 126732, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34332475

RESUMEN

Bio-heavy oil (BHO) is a renewable fuel, but its efficient use is problematic because its combustion may emit hazardous air pollutants (e.g., polycyclic aromatic hydrocarbon (PAH) compounds, NOx, and SOx). Herein, catalytic fast pyrolysis over HZSM-5 zeolite was applied to upgrading BHO to drop-in fuel-range hydrocarbons with reduced contents of hazardous species such as PAH compounds and N- and S-containing species (NOx and SOx precursors). The effects of HZSM-5 desilication and linear low-density polyethylene (LLDPE) addition to the feedstock on hydrocarbon production were explored. The apparent activation energy for the thermal decomposition of BHO was up to 37.5% lowered by desilicated HZSM-5 (DeHZSM-5) compared with HZSM-5. Co-pyrolyzing LLDPE with BHO increased the content of drop-in fuel-range hydrocarbons and decreased the content of PAH compounds. The DeHZSM-5 was effective in producing drop-in fuel-range hydrocarbons from a mixture of BHO and LLDPE and suppressing the formation of N- and S-containing species and PAH compounds. The DeHZSM-5 enhanced the hydrocarbon production by up to 58.5% because of its enhanced porosity and high acid site density compared to its parent HZSM-5. This study experimentally validated that BHO can be upgraded to less hazardous fuel via catalytic fast co-pyrolysis with LLDPE over DeHZSM-5.


Asunto(s)
Contaminación del Aire , Biocombustibles , Biomasa , Catálisis , Sustancias Peligrosas , Calor
5.
J Hazard Mater ; 421: 126694, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34332483

RESUMEN

Although the compound pollution of microplastics and arsenic (As) in paddy soil can affect the growth and quality of rice, relevant research on this phenomenon was limited. Therefore, we combined a pot experiment with computational chemistry to explore the effects and mechanism of polystyrene (PSMP) and polytetrafluoroethylene (PTFE) microplastics on As bioavailability. PSMP and PTFE interacted with rice root exudates through van der Waals forces, approached the rice root system, inhibited root activity, reduced the relative abundance of Geobacteria and Anaeromyxobacter, and consequently reduced the iron plaques on the root surfaces. Consequently, As uptake by the rice was inhibited. PSMP and PTFE reduced the hemoglobin content by directly destroying its tertiary structure, thereby retarding rice growth. In contrast, As increased the hemoglobin content by inducing reactive oxygen species in rice. Under the influence of PSMP, PTFE, and As, the activities of soluble starch synthase and pyrophosphorylase in rice grains were inhibited, and starch accumulation decreased. Thus, PSMP, PTFE, and As reduced rice biomass and yield owing to their physiological toxicity and adverse impacts on root activity. Grain yields in soil with an As content of 86.3 mg·kg-1, 0.5% small particle-sized PSMP, and 0.5% small particle-sized PTFE decreased by 30.7%, 20.6%, and 19.4%, respectively, compared to the control. This study determined the comprehensive mechanism through which PSMP and PTFE affect As bioavailability, which is critical for managing rice biomass and low yields in As and microplastic co-contaminated soil.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Arsénico/análisis , Arsénico/toxicidad , Microplásticos , Plásticos/toxicidad , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad
6.
J Hazard Mater ; 421: 126678, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34333410

RESUMEN

Soil contamination by arsenic (As) presents a high risk to public health, necessitating urgent remediation. This study sought to develop an efficient strategy for the phytoremediation of As-contaminated soil. The effects of Stevia rebaudiana Bertoni residue (SR) on the available As (A-As) concentration of soil and As extraction from the soil by Pteris vittata L. were studied by soil simulation, pot, and field experiments. The A-As concentration in the soil simulation experiment increased significantly by 84.20% after 20 days. The biomass, As concentration, and total extracted As of SR-treated P. vittata L. in the pot experiment increased significantly by 50.66%, 120.2%, and 171.2%, respectively, compared to the untreated control. The SR-treated rhizosphere soil in the pot experiment displayed a significant 21.72% decrease in total As concentration. In the one-year field experiment, treatment with SR resulted in a significant 191.1% increase in As extraction by P. vittata L. and a significant 10.26% reduction in rhizosphere soil As concentration compared to the control. This study proposes a potential mechanism for SR-mediated enhancement of P. vittata L. As extraction ability and provides a new, economic, and environmentally friendly method for As-contaminated soil remediation.


Asunto(s)
Arsénico , Pteris , Contaminantes del Suelo , Stevia , Arsénico/análisis , Biodegradación Ambiental , Suelo , Contaminantes del Suelo/análisis
7.
J Hazard Mater ; 421: 126731, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34339987

RESUMEN

Citric acid (CA) is the major exudate of rice roots, yet the effects of CA on arsenic (As) transformation and microbial community in flooded paddy soil have not been clearly elucidated. In this study, microcosms were established by amending CA to As contaminated paddy soils, mimicking the rhizosphere environment. Results showed that 0.5% CA addition significantly enhanced As mobilization after one-hour incubation, increased total As in porewater by about 20-fold. CA addition induced arsenate release into porewater, and subsequently formed ternary complex of As, iron and organic matters, inhibiting further As transformation (including arsenate reduction and arsenite methylation). Furthermore, the results of linear discriminant analysis (LDA) effect size (LEfSe) and network analysis revealed that CA addition significantly enriched bacteria associated with arsenic and iron reductions, such as Clostridium (up to 35-fold) and Desulfitobacterium (up to 4-fold). Our results suggest that CA exhibits robust ability to mobilize As through both chemical and microbial processes, increasing the risk of As accumulation by rice. This study sheds light on our understanding of As mobilization and transformation in rhizosphere soil, potentially providing effective strategies to restrict As accumulation in food crops by screening or cultivating varieties with low CA exuding.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Arsénico/análisis , Ácido Cítrico , Rizosfera , Suelo , Contaminantes del Suelo/análisis
8.
J Hazard Mater ; 421: 126750, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34339988

RESUMEN

The biological mechanisms underlying the associations between atmospheric ozone exposure and adverse cardiometabolic outcomes are yet to be identified. Imbalanced autonomic nervous system (ANS) as well as activations of the sympatho-adrenomedullary (SAM) and hypothalamic-pituitary-adrenal (HPA) axes are among possible early biological responses triggered by ozone, and may eventually lead to cardiometabolic abnormalities. To determine whether acute ozone exposure causes ANS imbalance and increases the secretion of neuroendocrine stress hormones, we conducted a randomized, double-blind, crossover trial, under controlled 2-hour exposure to either ozone (200 ppb) or clean air with intermittent exercise among 22 healthy young adults. Here we found that, compared to clean air exposure, acute ozone exposure significantly decreased the high-frequency band of heart rate variability, even after adjusting for heart rate and pre-exposure to ambient air pollutants and meteorological factors. Ozone exposure also significantly increased the serum levels of stress hormones, including corticotrophin-releasing factor, adrenocorticotropic hormone, adrenaline, and noradrenaline. Metabolomics analysis showed that acute ozone exposure led to alterations in stress hormones, systemic inflammation, oxidative stress, and energy metabolism. Our results suggest that acute ozone exposure may trigger ANS imbalance and activate the HPA and SAM axes, offering potential biological explanations for the adverse cardiometabolic effects following acute ozone exposure.


Asunto(s)
Contaminantes Atmosféricos , Ozono , Estudios Cruzados , Frecuencia Cardíaca , Hormonas , Humanos , Ozono/toxicidad , Adulto Joven
9.
J Hazard Mater ; 421: 126647, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34358970

RESUMEN

Contamination of paddy soils by arsenic (As) is of great concern for human health and the environment. The impact of animal-derived biochar on As mobilization under fluctuating redox conditions in paddy soils has not been studied. Consequently, we investigated the effects of pig carcass-derived biochar (PB) on As (im)mobilization in a contaminated paddy soil under controlled redox potential (Eh) using a biogeochemical microcosm-setup. The addition of PB decreased the concentration of dissolved As at Eh = +100 and +200 mV by 38.7% and 35.4%, respectively (compared to the control), because of the co-precipitation of As with Fe-Mn oxides and the complexation between As and aromatic organic molecules. However, under reducing conditions (Eh = -300 mV), PB increased the dissolved As by 13.5% through promoting reduction and decomposition of As-bearing Fe minerals (e.g., ferrihydrite-As, Fe-humic-As). Under oxidizing conditions (Eh = +250 mV), PB increased the dissolved As by 317.6%, due to the associated increase of pH. We conclude that As mobilization in PB-treated paddy soils is highly affected by Eh. PB can be used to reduce the environmental risk of As under moderately reducing conditions, but it may increase the risk under highly reducing and oxidizing conditions in paddy soils.


Asunto(s)
Arsénico , Oryza , Contaminantes del Suelo , Animales , Carbón Orgánico , Oxidación-Reducción , Suelo , Contaminantes del Suelo/análisis , Porcinos
10.
J Hazard Mater ; 421: 126712, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34388919

RESUMEN

Aquaculture is increasing at the global scale, and beneficial reuse of wastewater is becoming crucial in some regions. Here we selected a unique tertiary treatment system for study over a one-year period. This experimental ecosystem-based approach to effluent management included a treated wastewater pond (TWP), which receives 100% effluent from a wastewater treatment plant, and an aquaculture pond (AP) that receives treated water from the TWP for fish production. We examined the fate of a wide range of pharmaceutically active compounds (PhACs) in this TWP-AP system and a control pond fed by river water using traditional grab sampling and passive samplers. We then employed probabilistic approaches to examine exposure hazards. Telmisartan, carbamazepine, diclofenac and venlafaxine, exceeded ecotoxicological predicted no effect concentrations in influent wastewater to the TWP, but these water quality hazards were consistently reduced following treatment in the TWP-AP system. In addition, both grab and passive sampling approaches resulted in similar occurrence patterns of studied compounds, which highlights the potential of POCIS use for water monitoring. Based on the approach taken here, the TWP-AP system appears useful as a tertiary treatment step to reduce PhACs and decrease ecotoxicological and antibiotic resistance water quality hazards prior to beneficial reuse in aquaculture.


Asunto(s)
Preparaciones Farmacéuticas , Contaminantes Químicos del Agua , Animales , Acuicultura , Ecosistema , Monitoreo del Ambiente , Estanques , Aguas Residuales/análisis , Agua , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
11.
Environ Monit Assess ; 193(10): 682, 2021 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-34595610

RESUMEN

Local primary emissions of air pollutants are responsible for public health, decreasing productivity, and cultural activities in local residential areas. In this study, an integrated air quality observation and modeling system with a geographical information system (GIS) was developed to characterize the air pollution caused by local primary emission sources. This integrated system could provide air quality monitoring, data analysis, and visualization results that reflect air pollutant concentration data in a study area containing a local rural village (LRV) and an asphalt manufacturing facility (AMF). Additionally, the model was used to estimate the contributions of air quality from an emission source at the receptor and determine the control factor for the emission rate or meteorological changes. From the forward and backward modeling results, we found that the concentrations of particulate matter smaller than 2.5 µm (PM2.5) concentrations in the village were affected by the unique meteorological and emission conditions. The PM2.5 concentration was significantly increased for the cases with a slow wind speed of 1 m/s or high wind speed of 3 m/s, with an emission rate of 10 g/s. The contribution of AMF emissions was explained by contribution factor analysis. During the study period of December 2014-December 2015, the incoming contribution of PM2.5 at the LRV measurement station was approximately 47.6%. These results suggest that the proposed method can be useful for understanding adverse air quality conditions and estimating the emissions of air pollutants from primary sources for local environmental and public health authorities.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Monitoreo del Ambiente , Sistemas de Información Geográfica , Material Particulado/análisis
13.
Environ Monit Assess ; 193(11): 697, 2021 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-34618243

RESUMEN

Short-duration high-strength human tourism activities (SHHTA) can result in more air pollution emissions owing to increase motor vehicle usage, energy consumption and cooking fume emissions. Because of the strong uncertainty of human tourism behaviour, it is difficult to accurately assess the impact of SHHTA on air quality of natural scenic spots. To overcome this difficulty, we propose a novel ensemble empirical mode decomposition and detrended cross-correlation analysis (EEMD-DCCA) model to assess the influence of short-duration high-strength human tourism activities (SHHTA) on air quality. Zhangjiajie in China was selected as the study area. Hourly concentrations of NO2 were analysed from 1 January 2016 to 31 December 2018 at two monitoring sites, in an urban area and a scenic spot. Through EEMD, the main modes of NO2 with short-duration high-frequency were obtained for both sites. The DCCA method was used to study the cross-correlation relationship between high-frequency modes of NO2 for the urban area and scenic spot. The results show that high-frequency modes of NO2 between the two sites displayed long-range cross-correlation at the 24-h time scale. Furthermore, the quantitative impacts of meteorological factors (e.g. precipitation, temperature, and wind speed) on the DCCA exponent for high-frequency modes of NO2 at the two sites were investigated. The novel model proposed in this study is not restricted by the uncertainty of pollution emission inventory. The relationship between meteorological factors and DCCA exponents corresponds to the hypothesis that NO2 pollution of the natural scenic spot mainly came from SHHTA.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , China , Monitoreo del Ambiente , Humanos , Turismo
14.
Environ Monit Assess ; 193(11): 707, 2021 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-34623523

RESUMEN

Today, environmental pollution, air pollution in particular, is among the most important problems in the world. Air pollution, which has become a global issue, is estimated to cause the death of around 1 in 8 people worldwide. Due to the significance of air pollution, all components of air pollution are of great importance for human health, and thus the studies on air pollution are highly important, especially in areas with high population density. In this study, it was aimed to determine the regional and periodic change of CO2 and particulate matter pollution in the city of Misurata, one of the important cities of Libya. The study was conducted in the city centre of Misurata, and the measurements were made once in every three days between November and February at 7 different locations selected in the city centre. As a result of the measurements made, the changes in the pollution parameters were evaluated on the basis of zones and months. As a result of the study, the cleanest areas were found to be the industrial area (B3) located in the east of the city and the zone (B4), where the Al-Swehli farm was located, while the dirtiest areas were found to be the main street (B1 and B2) in the city centre and the city centre, in general. In terms of months, the lowest CO2 values were obtained in January, and the highest value was in February, whereas the lowest particulate matter values were obtained in January and the highest values in December.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Dióxido de Carbono , Monitoreo del Ambiente , Humanos , Material Particulado/análisis
15.
Waste Manag ; 135: 437-447, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34619625

RESUMEN

The current derived models for predicting polychlorinated dibenzo-p-dioxins and -furans (PCDD/F) emissions from incineration can only be applied to a specific incinerator due to high deviation or systematic errors. And the models fail to provide quantized guidance for the operation of full-scale municipal solid waste incinerators. To address the problem, explainable Bayesian support vector regression (E-BSVR) has been established to generalized predict and maximumly reduce the PCDD/F emissions. First, forty-two PCDD/F samples were determined from a whole year experiment in a full-scale incinerator. Meanwhile, 1,2,4-trichlorobenzene(1,2,4-TrCBz), carbon monoxide, sulfur dioxide, oxynitride, particulate matter, fluoride, and hydrogen chloride were measured, as input features. Second, after box-cox transformation normalization, and hyperparameters tuning, the R-Squared and root mean square error (RMSE) of the proposed method are 0.983 and 0.044, exhibiting high accuracy. The high accuracy (R-Squared = 0.992) and generalization are also proven on the dataset with high PCDD/F emissions. Then, the performances of BSVR are compared with kernel ridge regression, multiple linear regression, and unary linear regression, indicating afar smaller RMSE of BSVR. Finally, the optimal operating parameters are calculated through local interpretable model-agnostic explanations and the partial dependence plot. Results indicate that reducing the content of organic chlorine in municipal solid waste and inhibiting the deacon reaction are important methods for reducing PCDD/F emissions. The optimal operating parameters for the maximal reduction of PCDD/F emissions are 1,2,4-TrCBz < 0.098 ug/m3, fluoride > 0.452 mg/m3. As a whole, the E-BSVR method can be used as a reliable and accurate approach for the prediction and reduction of PCDD/F emissions.


Asunto(s)
Contaminantes Atmosféricos , Benzofuranos , Dibenzodioxinas Policloradas , Contaminantes Atmosféricos/análisis , Teorema de Bayes , Benzofuranos/análisis , Dibenzofuranos Policlorados/análisis , Monitoreo del Ambiente , Fluoruros , Incineración , Dibenzodioxinas Policloradas/análisis
16.
Environ Monit Assess ; 193(11): 726, 2021 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-34655335

RESUMEN

The present study provides the first multi-year (2015-2020) random observation of black carbon (BC) aerosols from pristine localities along the Gangotri Glacier Valley in the north-western Indian Himalaya. Due to the harsh climatic conditions and inaccessible terrain, hardly any BC observation is available from glaciated Himalaya. To investigate the background concentration of BC in the high Himalaya, random measurements are conducted at five locations at variable microclimates with different anthropogenic influences along a 24-km-long Gangotri Glacier Valley trek, viz. Gangotri (~ 3200 m amsl), Chirbasa (~ 3600 m amsl), Bhojbasa (~ 3800 m amsl), Gaumukh (~ 4000 m amsl), and Tapovan (~ 4400 m amsl). A relatively high concentration of BC (up to 2.23 ± 0.57 µg m-3) was recorded at Gangotri which is a famous Indian pilgrimage centre which remains highly crowded during the peak tourist season, i.e. May-June and Oct-Nov every year. Surprisingly, we also recorded high BC (up to 1.27 ± 0.57 µg m-3) at Tapovan, which is a high altitude meadow surrounded by high ice-snow peaks, viz. Bhagirathi Peak (6856 m amsl), Shivling (6543 m amsl), and Meru Parvat (6660 m amsl). The HYSPLIT cluster trajectory and CALIPSO data images suggest that besides local anthropogenic activities, polluted air mass-produced due to burning of forest and agriculture biomass and fossil fuels, etc. transported from Indo Gangetic Basin might be playing a potential role in ambient BC concentration in the study area. The present preliminary investigations of BC in the Gangotri Glacier Valley open new vision and possibilities for further extensive ground-based observation of aerosol air pollutants in Himalayan glacier valley systems.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Aerosoles/análisis , Contaminantes Atmosféricos/análisis , Carbono/análisis , Ecosistema , Monitoreo del Ambiente , Cubierta de Hielo , Proyectos Piloto
17.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3327-3334, 2021 Sep.
Artículo en Chino | MEDLINE | ID: mdl-34658219

RESUMEN

In this study, we examined the toxic effect of sublethal doses of acetochlor (1, 2, 4, 8 mg·kg-1) on earthworms by exogenous addition. The growth inhibition rate, cytochrome P450 isozymes (CYP1A2, 2C9 and 3A4) activities and the metabolomics were analyzed after seven days of exposure, to infer the toxicity threshold of acetochlor, screen the sensitive biomarkers from the levels of the individual, detoxified enzymes and small molecular metabolites, and elucidate the underlying toxicity mechanism. The results showed that CYP1A2, 2C9 and 3A4 activities were all significantly inhibited, and that the levels of ten metabolites (fructose-6-diphosphate, cytosine monophosphate, uridine monophosphate, adenosine monophosphate, adenosine, xanthine, fumaric acid, dihydroxyglutaric acid, ornithine and 16-hydroxyeicosatetraenoic acid) were significantly decreased by acetochlor exposure. The levels of six metabolites (adenosine succinic acid, succinic acid, arginine, tryptophan, asparagine and phenylalanine) were significantly increased when earthworms being exposed to 2-8 mg·kg-1 acetochlor. Acetochlor exposure caused oxidative damage to earthworms, weakened the glycolysis, disturbed the tricarboxylic acid cycle, disordered the purine and pyrimidine metabolism, and impaired the amino acids metabolism. Compared with the end point at individual level, the above 16 small molecule metabolites and CYP isozymes activities were more sensitive to acetochlor exposure. It was thus recommended that CYP isozymes (1A2, 2C9, and 3A4) activities and small molecular metabolites could be used as a set of biomarkers to diagnose the acetochlor pollution, given their high sensitivity and accuracy.


Asunto(s)
Oligoquetos , Contaminantes del Suelo , Animales , Suelo , Contaminantes del Suelo/análisis , Contaminantes del Suelo/toxicidad , Toluidinas/análisis , Toluidinas/toxicidad
18.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3341-3348, 2021 Sep.
Artículo en Chino | MEDLINE | ID: mdl-34658221

RESUMEN

Crude oil may block soil pores, affect soil water repellency, and change soil water movement. In this study, soil column simulation was used to study the effects of different crude oil pollution levels (0, 0.5%, 1%, 2%, 4%) on the water infiltration processes in loessial soil and aeolian sandy soil. The results showed that soil wetting front speed and infiltration rate of those two soils decreased with increasing crude oil content. The time needed for wetting front reaching the bottom of the soil column was the longest under 4% crude oil polluted soil, which was 4 times and 48 times longer than that of no crude oil polluted soil for loessial soil and aeolian sandy soil, respectively. The cumulative infiltration of loessial soil decreased with increasing crude oil content, while it increased to the max and then decreased as the crude oil content increased in aeolian sandy soil. The cumulative infiltration curves of aeolian sandy soil with high crude oil contents (2% and 4%) presented "up-tail" phenomenon. Kostiakov infiltration model and Philip infiltration model could better fit the infiltration process than Green-Ampt model for loessial soil with different crude oil content. However, the two models could only well fit the infiltration process for aeolian sandy soil with low crude oil content (0, 0.5%, 1%). Crude oil pollution could significantly affect soil water infiltration process, especiall in aeolian sandy soil.


Asunto(s)
Contaminación por Petróleo , Petróleo , Contaminantes del Suelo , Arena , Suelo , Contaminantes del Suelo/análisis
19.
Ying Yong Sheng Tai Xue Bao ; 32(9): 3377-3384, 2021 Sep.
Artículo en Chino | MEDLINE | ID: mdl-34658225

RESUMEN

Urban street canyon is one of the most important characteristics and spatial forms of cities. It is one of the most frequently used public spaces in cities, with the most serious automobile exhaust pollution and the largest population density. The unreasonable space configuration and internal composition might decrease self-purification of urban ventilation but increase local air pollutant concentration. Here, we reviewed the impacts of street canyon morphology, street trees, vehicle flow and meteorological factors on the distribution of air pollutants in street canyons. We scrutinized the relevant methods of numerical simulation, wind tunnel experiments, and field monitoring on the distribution and diffusion of air pollutants in street canyons. We recommended that future research should concentrate on the impacts of various parameters on the distribution and diffusion of air pollutants based on the field monitoring data. Meanwhile, further research should develop optimization strategies for street canyon design which is conducive to the dispersion of air pollutants, and put forward scientific support and optimization scheme for the controlling of air pollutants from the perspective of urban planning and pattern optimization.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Atmosféricos/análisis , Ciudades , Conceptos Meteorológicos , Modelos Teóricos , Emisiones de Vehículos/análisis
20.
Artículo en Inglés | MEDLINE | ID: mdl-34639670

RESUMEN

Oxygen production in cryogenic air separation units is related to a significant carbon footprint and its supply in the medicinal sphere became critical during the recent COVID-19 crisis. An improved unit design was proposed, utilizing a part of waste heat produced during air pre-cooling and intercooling via absorption coolers, to reduce power consumption. Variable ambient air humidity impact on compressed air dryers' regeneration was also considered. A steady-state process simulation of a model 500 t h-1 inlet cryogenic air separation unit was performed in Aspen Plus® V11. Comparison of a model without and with absorption coolers yielded an achievable reduction in power consumption for air compression and air dryer regeneration by 6 to 9% (23 to 33 GWh year-1) and a favorable simple payback period of 4 to 10 years, both depending on air pressure loss in additional heat exchangers to be installed. The resulting specific oxygen production decrease amounted to EUR 2-4.2 t-1. Emissions of major gaseous pollutants from power production were both calculated by an in-house developed thermal power plant model and adopted from literature. A power consumption cut was translated into the following annual greenhouse gas emission reduction: CO2 16 to 30 kilotons, CO 0.3 to 2.3 tons, SOx 4.7 to 187 tons and NOx 11 to 56 tons, depending on applied fossil fuel-based emission factors. Considering a more renewable energy sources-containing energy mix, annual greenhouse gas emissions decreased by 50 to over 80%, varying for individual pollutants.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , COVID-19 , Gases de Efecto Invernadero , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Efecto Invernadero , Calor , Humanos , Oxígeno , SARS-CoV-2
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