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Effect of composted organic amendments and zinc oxide nanoparticles on growth and cadmium accumulation by wheat; a life cycle study
2020
Bashir, Arooj | Rizwan, Muhammad | Ali, Shafaqat | Adrees, Muhammad | Rehman, Muhammad Zia ur | Qayyum, Muhammad Farooq
Cadmium (Cd) availability in arable soils is a serious issue while little is known about the role of co-composted organic amendments and zinc oxide nanoparticles (ZnO-NPs) foliar spray on biomass and Cd accumulation in wheat grains. The current study investigated the soil application of organic amendment (composted biochar and farmyard manure) at a level of 0, 1, and 2% w/w and foliar spray of ZnO-NPs (0, 100, and 200 mg/L) on biomass, yield, and Cd in wheat grains cultivated in an aged Cd-contaminated agricultural soil. The results indicated that organic amendment increased the biomass, chlorophyll concentrations, yield, and activities of peroxidase and superoxide dismutase of wheat while decreased the electrolyte leakage and Cd concentrations in different parts of wheat such as shoots, roots, husks, and grains. This effect of organic amendment was further enhanced by the foliar spray of ZnO-NPs in a dose-additive manner. Cadmium concentration in grains was below threshold level (0.2 mg/kg DW) for cereals in combined application of 200 mg/L ZnO-NPs and 1% organic amendment as well as in higher treatment (2%) of organic amendment and NPs. Thus, combined use of organic materials and NPs might be a suitable way of reducing Cd and probably other toxic trace element concentrations in wheat and other cereals.
Mostrar más [+] Menos [-]Saponaria officinalis L. and Achillea millefolium L. as possible indicators of trace elements pollution caused by mining and metallurgical activities in Bor, Serbia
2020
Nujkić, Maja | Milić, Snežana | Spalović, Boban | Dardas, Anastassios | Alagić, Slađana | Ljubić, Darko | Papludis, Aleksandra
This study evaluates bioaccumulation and translocation potentials of trace elements (TEs) by Saponaria officinalis L. (soapwort) and Achillea millefolium L. (yarrow) in order to select and optimize phytoremediation methods for the polluted environment of the city of Bor, Serbia. According to the enrichment factor for soil (i.e., 57.9–128.8 for Cd and As), pollution index (i.e., 6.6–84.7 for Cu), pollution load index (2.9–98.8), individual potential risk factors (11.5–5163), and potential ecological risk index values (260–6379), urban and rural soils from the city of Bor were classified as very contaminated with the investigated TEs. The results from all the indices and statistical analysis showed significant ecological risks of Cu, As, and Cd at the investigated sites and urge the need for remediation. The enrichment factor of the plants for As (566.3) and Cd (306.2) indicated a high enrichment level of the herb organs at all the sites. Since there are small differences in metal accumulation index values between the herbs and their parts (root, shoot), soapwort and yarrow can be considered as potential bioindicators. Based on the biological concentration and translocation factors, soapwort can be recommended as a suitable herb for phytoextraction purposes of Pb, As, and Cd polluted areas. Yarrow shows good characteristics for phytoextraction of Cu, Pb, and As from the contaminated soil. Principal component analysis (PCA) and hierarchical cluster analysis (HCA) results indicate their similar origin from atmospheric deposition. Therefore, these herbs can be utilized as a bioindicator and phytoremediator in polluted areas influenced by metallurgical activities to detect possible levels of TEs.
Mostrar más [+] Menos [-]Correction to: A Review of the Techniques Used to Control Confounding Bias and How Spatiotemporal Variation Can Be Controlled in Environmental Impact Studies
2020
Hatami, Rezvan
Unfortunately, the Figure 1b was incorrectly captured in the published online paper.
Mostrar más [+] Menos [-]Genetic polymorphisms in XRCC1, OGG1, and XRCC3 DNA repair genes and DNA damage in radiotherapy workers
2020
Soliman, Asmaa H. M. | Zaki, Nasef N. | Fathy, Hala M. | Mohamed, Aml A. | Ezzat, Mohamed A. | Rayan, Amal
DNA damage may develop at any dose of ionizing radiation. DNA damage activates pathways that regulate cell growth and division or coordinate its replication and repair. The repair pathways, base excision repair (BER) and single-strand break repair (SSBR), can repair such damages efficiently and maintain genome integrity. Loss of this repair process or alteration of its control will be associated with serious outcomes for cells and individuals. This study aimed to determine the relationship between XRCC1 (Arg194Trp, Arg280His, and Arg399Gln), OGG1 (Ser326Cys), and XRCC3 (Thr241Met) SNPs and DNA damage and to identify high-risk individuals with reduced DNA repair capacity. This case-control study was conducted on 80 subjects; 50 subjects working in Clinical Oncology and Nuclear Medicine Department in Assiut University Hospital along with 30 controls. A total of 1 mL blood samples were collected for Single-Cell Gel Electrophoresis Technique (Comet Assay) for detection of DNA damage in those subjects. A total of 3 mL fresh blood samples were collected and analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP)–based technique. DNA damage detected by comet test was significantly high in IR-exposed workers than control. Statistically high significant difference was found in exposed subjects versus control subjects regarding the frequencies of the variant alleles of hOGG1³²⁶, XRCC1²⁸⁰ & ³⁹⁹, and XRCC3²⁴¹. The level of DNA damage was not affected by OGG1³²⁶ SNPs when comparing subjects of wild genotype with those of (pooled) variants either in the exposed staff or in the control group while XRCC1²⁸⁰, ³⁹⁹ and XRCC3²⁴¹ variant alleles had an influence on the studied DNA damage biomarker. Moreover, genotyping distribution pattern was highly variable in relation to gender. The present study indicated a relationship between DNA damage detected by comet test and single nucleotide polymorphisms in genes coding for DNA certain repair enzymes. Individuals occupationally exposed to low doses of ionizing radiation could be at great risk and more susceptible to the increased DNA damage if they have inherited genetic polymorphism.
Mostrar más [+] Menos [-]Adsorption Mechanism and Structure-Performance Relationship of Chromium Ions by Biochar
2020
Li, Menghong | Guo, Xiaoli | Wei, Ying | Liu, Aiju | Lu, Jie | Niu, Xiaoyin | Ma, Yanfei | Li, Shuang | Shang, Zhenxiao | Liu, Xinpeng
In order to further explore the adsorption mechanism of chromium ion by biochar, organic components (OCs) and inorganic components (ICs) of biochar (RC) were prepared, and adsorption experiments of chromium ions by these types of carbon (RC, OC, IC) were performed. The three types of carbon were characterized before and after adsorption of chromium ions, using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Boehm titration, and zero charge (pHₚzc). Results showed that the adsorption efficiency of IC on trivalent chromium (Cr³⁺) was the strongest, ion exchange of Cr³⁺ with metal cations present on IC being the main adsorption mechanism, accounting for 61% of the total adsorption capacity. Among the metal ions, K⁺ accounted for about 51%. The REDOX between Cr³⁺ and carboxyl accounted for 20% of the total adsorption capacity. Other adsorption mechanisms, such as chelation between Cr³⁺ and carboxyl, and co-precipitation between Cr³⁺ and carbonate, occupied a small proportion. OC showed the largest adsorption capacity to hexavalent chromium (Cr⁶⁺). The adsorption mechanism of OC to Cr⁶⁺ was the result of combined actions, such as electrostatic attraction, and REDOX between Cr⁶⁺ with the aromatic π-conjugated system and reductive functional groups like hydroxyl. Among them, the REDOX accounted for 53% of the total adsorption of Cr⁶⁺ by OC.
Mostrar más [+] Menos [-]Concentrations of serum cotinine across stages of glomerular function among US adult smokers and nonsmokers
2020
Jain, Ram B.
Data from National Health and Nutrition Examination Survey for 1999–2016 were used to investigate variabilities in serum cotinine levels for US adult smokers (N = 8951) and nonsmokers (N = 28,205) aged ≥ 20 years across the stages of glomerular function (GF). Those with serum cotinine levels < 3.3 ng/mL and did not report using any tobacco products during the last 5 days were classified as nonsmokers. Those with serum cotinine levels ≥ 3.3 ng/mL and reported using cigarettes, cigars, pipes, and/or water pipes with or without using e-cigarettes and/or smokeless tobacco products during the last 5 days were classified as nonsmokers. Those who had eGFR > 90 mL/min/1.73 m² were classified to be in GF stage 1 or GF-1, those with 60 ≤ eGFR ≤ 90 mL/min/1.73 m² were classified to be in GF-2, those with 45 ≤ eGFR < 60 mL/min/1.73 m² were classified to be in GF-3A, and those with 15 ≤ eGFR <45 mL/min/1.73 m² were classified to be in GF-3B/4. Among nonsmokers, except for females and non-Hispanic blacks, adjusted levels of serum cotinine (AGM) decreased relatively sharply from GF-1 to GF-2, stayed relatively stable at GF-2 and GF-3A, and then rose moderately to GF-3B/4. For example, for non-Hispanic whites, AGMs were 0.042, 0.033, 0.031, and 0.037 ng/mL at GF-1, GF-2, GF-3A, and GF-3B/4 respectively. Among smokers, except for females and non-Hispanic blacks, AGMs increased relatively sharply from GF-1 to GF-2 and then decreased from GF-2 to GF-3/4. For example, for males, AGMs were 151.9, 192.0, and 162.9 ng/mL at GF-1, GF-2, and GF-3/4 respectively. AGMs for male smokers were lower than for female smokers at GF-3/4 (162.9 vs. 197.2 ng/mL, p < 0.01). The order of AGMs by race/ethnicity was non-Hispanic blacks > non-Hispanic whites > Hispanics and others at every GF stage. AGMs at GF-3/4 were higher than AGMs at GF-1 for smokers.
Mostrar más [+] Menos [-]Efficiencies and mechanisms of steel slag with ferric oxides for removing phosphate from wastewater using a column filter system
2020
Ahmad, Siti Zu Nurain | Al-Gheethi, Adel | Hamdan, Rafidah | Othman, Norzila
The current study aimed to investigate the efficiencies and mechanisms of slag filter media for removing phosphorus from synthetic wastewater. The steel slag with high ferric oxides (Fe₂O₃) was subjected for the electric arc furnace (EAF) and selected as the filter media (HFe). The chemical characteristics of HFe were determined using pH, point of zero charge (PZC) and XRF. The phosphorus removal efficiency was studied in a designed vertical steel slag column rock filters in unaerated HFe (UEF) and aerated HFe (AEF) system. The microstructure of HFe was analyzed by FTIR, XRD and SEM-EDX analysis. The results of XRF revealed that ferric oxide (Fe₂O₃) ranged from 26.1 to 38.2%. PZC for Filter HFe was recorded at pH 10.55 ± 0.27. The highest efficiencies were recorded by UEF and AEF systems at pH 3 and pH 5 (89.97 ± 4.02% and 79.95 ± 6.25% at pH 3 and 72.97 ± 8.38% and 66.00 ± 12.85% at pH 5 for UEF and AEF, respectively). These findings indicated that AEF exhibiting higher removal than UEF systems might be due to presence high Fe concentration in AEF which play important role in the phosphorus removal. The main elements available on the surface of HFe included carbon, oxygen, iron, calcium, magnesium, silicon, platinum, sulphur, manganese, titanium and aluminium. The XRD analysis indicated that the precipitation of orthophosphate as calcium and iron-phosphates was the removal mechanism as confirmed using FT-IR analysis. These findings demonstrated the efficiency of HFe in removing of phosphorus from wastewater.
Mostrar más [+] Menos [-]Assessing potential aquatic toxicity of airport runoff using physicochemical parameters and Lemna gibba and Aliivibrio fischeri bioassays [Erratum: August 2021, v.28(32), p.44584]
2020
Calvo, Olga C. | Quaglia, Gisela | Mohiley, Anubhav | Cesarini, Maria | Fangmeier, Andreas
A critical problem derived from airport operations is the environmental impact of runoff water. Airport runoff includes a complex mixture of pollutants, e.g., from deicing agents, that may affect negatively natural water bodies. This study assesses the spatial and temporal aquatic ecotoxicity of runoff water and possible aeroplane drift in a German airport. Over winter 2012–2013, from November to May, water samples were collected within the airport and surrounding area. These samples were analyzed using traditional physicochemical analysis and biotests with two aquatic organisms from different trophic levels, Lemna gibba and Aliivibrio fischeri. Overall, the samples examined in this study were relatively non-toxic to the tested organisms. The physicochemical parameters were mainly influenced by the sampling period being higher in colder months. In contrast, the ecotoxicity was influenced by the sampling site. For sites within the airport, a high correlation between the physicochemical parameters (EC and TOC) and toxicity in L. gibba was found. These correlations were not evident in samples taken outside the airport or when A. fischeri was used as a bioindicator. However, a pronounced seasonality has been observed, linked to the coldest months with average inhibition values of 50% in L. gibba and 25% in A. fischeri, particularly in January. Both biotests yielded differing results; therefore, more biotests should be included. However, L. gibba showed a good response with this type of water samples to be included in future studies together with detailed chemical analysis. The present study provides data to assess the potential ecotoxicological effects of airport runoff affected by winter operations.
Mostrar más [+] Menos [-]Copper Nanoclusters/Red Globe Flower Carbon as a Fenton-Like Catalyst for the Degradation of Amido Black 10B
2020
Xie, Chunsheng | Wen, Xinyi | Xiao, Chun | Wei, Shoulian | Wu, Xiange | Liu, Shasha | Cao, Jiangfei
Cu-based copper nanoclusters have generated a great deal of interest based on for their fluorescent and catalytic properties. However, as heterogeneous catalysts, little attention has been given to the degradation of organic pollutants in Fenton-like reaction systems. Here, flower-like copper nanoclusters/flower carbon heterostructured microspheres were prepared by a one-pot mixing template-based method. With Cu-based copper nanoclusters/carbon (CuNCs/C) composite as a Fenton-like catalyst, a CuNCs/C-H₂O₂ system was used to degrade Amido Black 10B (AB-10B). The effects of different factors on the degradation rate of AB-10B were studied. A 98.6% degradation ratio of AB-10B was reached for the CuNCs/C -H₂O₂ based Fenton-like reaction within 180 min under optimal experimental conditions. The CuNCs/C concentration was 0.06 g/L, the dosage of H₂O₂ was 25 mmol/L, the mass ratio of CuNCs and the carbon was 1:2, pH = 6.0, and the reaction temperature was 40.0 °C. The removal rate of AB-10B on CuNCs/C decreased by less than 10% even after 6 catalytic cycles, which showed a remarkable reusability characteristic and high catalytic activity. Cu⁰ and Cu⁺ were found to co-exist in the catalysts and presented a high degradation effective for intermediates that were identified by liquid chromatography-mass spectrometry (LC-MS). These results indicated that the catalysts can be used as highly efficient Fenton-like catalyst for the degradation of toxic organic pollutants in wastewater. Graphical Abstract
Mostrar más [+] Menos [-]Identification of Pesticide Residues and Prediction of Their Fate in Agricultural Soil
2020
EL-Saeid, Mohamed H. | Alghamdi, Abdulaziz G.
Fourteen pesticides were screened and determined through quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction process combined with GC-MS/MS in arid agriculture soil. The aims of the current investigation were to account the occurrence of organochlorine (OCP) and organophosphates (OPP) pesticide residues as well as other groups of pyrethroids (PYRs), carbamates, and biopesticides using a combined of QuEChERS and GC-MS/MS techniques in agriculture soils at Al-Kharj region, Saudi Arabia, and to investigate correlation between pesticide losses in soils and some physicochemical characteristics of pesticides including an octanol-water coefficient partition (Kₒw) and the vapor pressure (Vp). Prediction of pesticide fate by considering both pesticide and soil physio-chemical properties will facilitate the management of pesticide application and minimize the hazards of environmental pollution. The fate of pesticide residue in soils is generally controlled by soil/air exchange, water interaction, and biodegradation. The results indicated that 14 pesticide residues were measured in collected samples of various soils, spinosad, chlorpyrifos methyl, dimethoate, chlorpyrifos, lindane (γ-HCH), permethrin, and methomyl which were the most abundant sources of contamination in the studied region. p,p-DDT, o,p-DDT, bifenthion, β-cyfluthrin, and methidathion were less commonly detected. Single parameter least squares regression equations (sp-LSRE) for Vp and Kₒw against the loss of each pesticide residue showed a significant change in concentration levels (p < 0.05) between the two seasons. The results showed that vapor pressure and octanol-water partition coefficient data are not enough to model pesticide residue losses in arid low organic carbon soil. More soil-related data is needed to describe the dissipation mechanisms of these pesticide residues in the region.
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