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Understanding corporate surplus food donation in China: testing the roles of environmental concern, altruism, past experience, and perceived risk Texte intégral
2019
Liao, Chuanhui | Hong, Jin | Zhao, Dingtao
This paper investigates the motives behind corporate giving and determines whether perceived risk plays a major role in corporate surplus food donation intention. A conceptual model is developed from the perspectives of perceived risk, economic concern, past behavior, and moral motives. A questionnaire survey is conducted among food manufacturers and retailers in the Sichuan Province in China. A total of 143 valid observations are used to conduct structural equation modeling analysis. The results show that corporate reputation, legislation, and business risks are the main sub dimensions of risks that corporations perceive. Perceived risk, past behavior, environmental concern, and altruism affect corporate donation intention significantly. Implications of the findings for promoting surplus food donation are also discussed.
Afficher plus [+] Moins [-]Exposure index of methyl isocyanate (MIC) gas disaster and a comprehensive spectrum of cytogenetic analysis after 30 years Texte intégral
2019
Ganguly, Bani Bandana
Severity of clinical expression and high mortality could not facilitate establishing exposure index/association following MIC disaster in Bhopal. Mortality-based exposure stratification was critiqued by the International Medical Commission on Bhopal (IMCB). IMCB stratified exposure considering distance as surrogate at 2 km intervals after 10 years. The first follow-up cytogenetic screening of the pre-screened survivors after 30 years has demonstrated chromosome abnormalities (CA). Exposure stratification was attempted considering cytogenetic screening conducted during 1986–1988. Elevation of CA appeared proportional to exposure status and authenticated the initial mortality-based stratification. The one-on-one comparison of the previous and present cytogenetics has described the individual response to MIC exposure over 30 years. Chi-square test has been carried out for checking the cytogenetic changes at the individual level statistically, which revealed that differences of chromosomal aberrations collected immediately post-disaster and 30 years later are nonsignificant. The prominence of interindividual variation was noticed in general. The impact of overall exposure was higher in males. Constitutional abnormalities in 8.5% of the study population, including translocation, inversion, deletion, fragile sites, etc., necessitate screening of blood-linked members. The incidence of acrocentric association was prominent in the study population. Normal karyotype in children born to severely exposed parents with congenital anomalies indicates necessity of molecular karyotyping and/or screening of mutations. The study highlights follow-up of the health of the index cases at shorter (3–6 months) intervals. This comprehensive spectrum of cytogenetic report highlights immediate post-disaster chromosomal aberrations, the changes that occurred over 30 years in conjunction with other environmental factors at the individual level, constitutive genomic aberrations, polymorphic variations, and chromosomal patterns in congenitally malformed children of the survivors, which collectively indicate the possibility of acquisition/persistence of stable aberrations in MIC-exposed lymphocytes through interaction with environmental/biological confounders.
Afficher plus [+] Moins [-]Single and combined effects of microplastics and roxithromycin on Daphnia magna Texte intégral
2019
Zhang, Peng | Yan, Zhenhua | Lü, Guanghua | Ji, Yong
There is a rising concern about the pollution of microplastics (plastic particles < 5 mm) in water due to their physicochemical properties, especially their interaction with organic contaminants; however, such knowledge is still limited. The mass production and consumption of medication for the treatment of infectious diseases in human and animals have led to the ubiquity of antibiotics in the environment. We studied the single and joint effects of microplastics (1-μm and 10-μm polystyrene particles, PS) and roxithromycin (ROX) on Daphnia magna through the acute and sublethal toxicity tests. The 48-h median effective concentration (EC₅₀) of 1-μm and 10-μm PS to D. magna was 66.97 mg/L and 199.94 mg/L, respectively, while the value of ROX was 20.28 mg/L. Malondialdehyde (MDA) levels and the activities of four enzymatic biomarkers, including superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and glutathione S-transferase (GST), were further detected to assess the oxidative stress caused in D. magna caused. The results showed that 48-h exposure to PS (0.1 mg/L) or ROX (0.01 mg/L) alone activated the activities of CAT and GST and MDA levels. When compared with the ROX alone, the responses of GPx and MDA in D. magna co-exposed to 1-μm PS were significantly decreased, while co-exposure to 10-μm PS significantly decreased the responses of GST and MDA. Furthermore, the integrated biomarker response version 2 (IBRv2) analysis revealed that co-exposure to 1-μm PS and ROX led to the strongest biological responses in D. magna. Our findings underlined that microplastics should be a concern when they interact with the co-existence of pollutants in the aquatic environment.
Afficher plus [+] Moins [-]Modification of the Relative Abundance of Constituents Dissolved in Drinking Water Caused by Organic Pollution: a Case of the Toluca Valley, Mexico Texte intégral
2019
de Oca, Reyna María Guadalupe Fonseca-Montes | Ramos Leal, Alfredo | Solache-Ríos, Marcos José | Martínez-Miranda, Verónica | Fuentes Rivas, Rosa María
Drinking water contains geogenic elements to which human beings are exposed; in the long term, these elements can be either harmful (As) or beneficial (Mg and Ca) to health. The composition and relative abundance of the constituents in groundwaters are conditioned by the balance between dissolution, precipitation, and oxide-reduction processes also by the nature and spatial arrangement of the materials interacting with the water. In recent decades, human activities and changes in the use of land have led to the accumulation of organic materials and their degradation into nitrogen and phosphorus, which has resulted in a change of the physicochemical composition and quality of drinking water. The main target of the study was to evaluate the effect of contamination by nitrogen and phosphate organic matter on the physicochemical composition of water used for human consumption. The study was conducted in the Toluca Valley aquifer. The determination of parameters in situ and analysis in the laboratory of physicochemical parameters revealed the presence of NO₃⁻ (1.0–119 mg L⁻¹), SO₄²⁻ (6.81–24.70 mg L⁻¹), PO₄³⁻ (2.50–32.20 mg L⁻¹), and N-NH₄⁺ (0–5.40 mg L⁻¹), which suggested the presence of punctual anthropogenic contamination; this was confirmed using 3D fluorescence to identify the presence of organic matter. The results of Na⁺ (15.75 mg L⁻¹), K⁺ (2.66 mg L⁻¹), Ca²⁺ (8.73 mg L⁻¹), and Mg²⁺ (8.01 mg L⁻¹) using the ICP technique showed that the water supplied in the area has a low mineral content. Correlation between P and cations Ca²⁺ (0.844) > Na⁺ (0.720) > Mg²⁺ (0.694) > K⁺ (0.60) indicates that anthropic contamination affects the relative abundance of dissolved constituents in water. The scarcity of essential nutrients in water impacts on public health; it has been reported that deficiency of Ca²⁺ and Mg² implies a wide variety of clinical conditions, mainly in the development of cardiovascular diseases.
Afficher plus [+] Moins [-]Shift of Soil Polycyclic Aromatic Hydrocarbons (PAHs) Dissipation Pattern and Microbial Community Composition due to Rhamnolipid Supplementation Texte intégral
2019
Lu, Lu | Zhang, Jing | Peng, Chao
Biosurfactants are promising substitutes for chemical surfactants during polycyclic aromatic hydrocarbon (PAH) bioremediation. However, recent studies have revealed contrasting findings and critical knowledge gaps regarding the impacts of biosurfactants on the soil PAH biodegradation efficiency and microbial community. Here, a laboratory study was conducted to evaluate the impact of rhamnolipid on the PAH dissipation efficiency and microbial community structure during the time-course incubation. The data showed that the contribution ratio of biotic loss and abiotic loss depended on the ring number of PAH. In the microcosms supplemented with 20 μg g⁻¹ rhamnolipid, the biodegradation efficiencies of phenanthrene, fluoranthene, and pyrene increased by 10.1%, 12.3%, and 22.0%, respectively, compared to those in the rhamnolipid-free treatment after incubation for 7 days. In contrast, rhamnolipid either had no impact on or inhibited PAH degradation in the later time points (21–35 days). The abundance of bacterial 16S rRNA and phnAc genes showed significant increase in soil amended of both PAH and rhamnolipid. MiSeq sequencing results revealed that potential PAHs-degrading Massilia, Bacillus, Lysobacter, Archrobacter, and Phenylobacterium became dominant genera in PAH treatment, irrespective of the rhamnolipid added. Nevertheless, PAH addition in the presence of rhamnolipid also significantly stimulated the growth of Delftia, Brevundimonas, Tumebacillus, and Geobacillus. In contrast, the rhamnolipid altered the microbial community composition through the selection of Gaiella, Solirubrobacter, Nocardioides, and Bacillus. The results reveal the intensive selectivity effect of PAH and rhamnolipid on the soil microbes that are involved in bioremediation, and highlight the positive effect on PAHs biodegradation.
Afficher plus [+] Moins [-]Improving the Growth of Rapeseed (Brassica chinensis L.) and the Composition of Rhizosphere Bacterial Communities through Negative Pressure Irrigation Texte intégral
2019
Zhao, Xiujuan | Gao, Xiang | Zhang, Shuxiang | Long, Huaiyu
Negative pressure irrigation (NPI) is a new water supply technology that can save water and improve fertilizer utilization efficiency. The objective of this study was to determine the effects of different irrigation treatments on the yield and quality of rapeseed, nitrate distribution in soil, and the composition of rhizosphere bacterial communities in a greenhouse. During the entire rapeseed growth period, NPI reduced water consumption by 23 and 23% compared to that reduced by conventional irrigation (CI) and drip irrigation (DI), and NPI improved water use efficiency (WUE) by 67 and 59% more than CI and DI, respectively. Under NPI, the soil water content remained relatively stable within the range of 9.7–11.7%, which was a lower range of variation than that under CI and DI of 8.6–13.3%. NPI significantly improved the yield, quality, and plant nutrients of rapeseed. The NO₃-N content was always lowest at the different sampling times and soil layers under the NPI-L treatment. NPI significantly increased the microbial diversity in the rhizosphere soil of rapeseed and increased the abundance of Actinobacteria while decreasing that of Proteobacteria and Acidobacteria. Simultaneously, the performance of rapeseed was better under the NPI-L fertilizer concentration (0.15%) than under NPI-H (0.20%). Eventually, the combination of the evaluated regimes demonstrated that NPI is the best irrigation technique for saving water and obtaining relatively high rapeseed yields and quality while improving nitrogen utilization and the composition of rhizosphere bacterial communities. The results of this study provide a scientific basis for planting rapeseed in agricultural facilities.
Afficher plus [+] Moins [-]Dinitrodiazophenol industrial wastewater treatment by a sequential ozone Fenton process Texte intégral
2019
Gu, Zhepei | Pan, Xuqin | Guo, Shengpeng | Zhang, Aiping
The ozonation process is efficient in degrading aromatic substances and substances with unsaturated bonds, but cannot effectively destroy small-molecule organic compounds, which accumulate. Likewise, the Fenton process is a classic wastewater treatment method, but requires strict pH control and produces secondary pollution when the concentration of organic substances is high. In this study, we applied a 1stO₃-2ndFenton sequential process to treat diazodinitrophenol (DDNP) industrial wastewater and provide suitable reaction conditions for Fenton process. For the 1stOzone process, organics removal increased as O₃ dosage increased. At optimized operation, the 1stO₃ process provided an acidic effluent (pH = 3) and reduced the organics concentration to a level suitable for the 2ndFenton process. Benzene ring substances as well as nitro group and diazo group compounds were greatly degraded in the 1stO₃ process and were further mineralized in the 2ndFenton process. Additionally, the biodegradability of DDNP industrial wastewater was greatly improved. This is the first reported time that ozonation and the Fenton process have been integrated sequentially to treat an explosive production wastewater. The study provides a feasible chemical oxidation method for treating DDNP industrial wastewater by simply combining two classic treatment processes.
Afficher plus [+] Moins [-]Application of Carboxymethyl Cellulose–Stabilized Sulfidated Nano Zerovalent Iron for Removal of Cr(VI) in Simulated Groundwater Texte intégral
2019
Zhao, Lingzi | Zhao, Yongsheng | Yang, Bingjun | Teng, Honghui
Carboxymethyl cellulose–stabilized sulfidated nano zerovalent iron (CMC-S-nZVI) was tested for its capacity to the removal of Cr(VI) in this study. The effect of synthesis approaches on morphology and properties of CMC-S-nZVI was studied. Results revealed CMC-S-nZVI prepared by the surface corrosion method had favorable homogeneity and corrosion resistance. The structure and morphology of CMC-S-nZVI particles were investigated by transmission electron microscopy, X-ray powder diffraction, and Fourier-transform infrared spectrometry. Batch experiments showed that the removal efficiency of Cr(VI) by the CMC-S-nZVI particles was influenced by the S/Fe molar ratio, initial pH, initial Cr(VI) concentration, and the reaction temperature. Increasing S/Fe molar ratio from 0 to 0.35 enhanced Cr(VI) removal efficiency from 65.37 to 85.08%. Reducing pH value and improving the reaction temperature have a positive impact on Cr(VI) removal. The removal amount was 535 mg/g (total iron) CMC-S-nZVI with initial Cr(VI) concentration of 50 mg/L. Compared with CMC-nZVI, CMC-S-nZVI had better performance in Cr(VI) removal in a simulated groundwater system. The results indicated that CMC-S-nZVI might be applicable for in situ treatment of the Cr(VI)-containing groundwater.
Afficher plus [+] Moins [-]Laboratory-Scale Evaluation of the Effects of Water-Filled Pore Space on Emissions of CO2, CH4, N2O, and N2 from Soil-Based Wastewater Treatment Texte intégral
2019
Anderson, Faith L. | Cooper, Jennifer A. | Amador, José A.
Microbial removal of C and N in soil-based wastewater treatment involves emission of CO₂, CH₄, N₂O, and N₂ to the atmosphere. Water-filled pore space (WFPS) can exert an important control on microbial production and consumption of these gases. We examined the impact of WFPS on emissions of CO₂, CH₄, N₂O, and N₂ in soil microcosms receiving septic tank effluent (STE) or effluent from a single-pass sand filter (SFE), with deionized-distilled (DW) water as a control. Incubation of B and C horizon soil for 1 h (the residence time of wastewater in 1 cm of soil) with DW produced the lowest greenhouse gas (GHG) emissions, which varied little with WFPS. In B and C horizon soil amended with SFE emissions of N₂O increased linearly with increasing WFPS. Emissions of CO₂ from soil amended with STE peaked at WFPS of 0.5–0.8, depending on the soil horizon, whereas in soil amended with SFE, the CO₂ flux was detectable only in B horizon soil, where it increased with increasing WFPS. Methane emissions were detectable only for STE, with flux increasing linearly with WFPS in C horizon soil, but no clear pattern was observed with WFPS for B horizon soil. Emissions of GHG from soil were not constrained by the lack of organic C availability in SFE, or by the absence of NO₃ availability in STE, and addition of acetate or NO₃ resulted in lower emissions in a number of instances. Emission of ¹⁵N₂ and ¹⁵N₂O from ¹⁵NH₄ took place within an hour of contact with soil, and production of ¹⁵N₂ was much higher than ¹⁵N₂O. ¹⁵N₂ emissions were greatest at the lowest WFPS value and diminished markedly as WFPS increased, regardless of water type and soil texture. Our results suggest that the fluxes of CO₂, CH₄, N₂O, and N₂ respond differently to WFPS, depending on water type and soil texture.
Afficher plus [+] Moins [-]Fungal and Bacterial Co-Bioaugmentation of a Pesticide-Degrading Biomixture: Pesticide Removal and Community Structure Variations during Different Treatments Texte intégral
2019
Castro-Gutiérrez, Víctor | Masís-Mora, Mario | Carazo Rojas, Elizabeth | Mora-López, Marielos | Rodríguez-Rodríguez, Carlos E.
Biopurification systems (BPS) are employed for the treatment of pesticide-containing wastewaters. In this work, a biomixture (active core of BPS) complemented by the addition of the fungus Trametes versicolor was evaluated for the elimination of a mixture of pesticides under different treatment conditions. The biomixture achieved high removal of all the pesticides assayed after 16 d: atrazine (68.4%, t₁/₂: 9.6 d), carbendazim (96.7%, t₁/₂: 3.6 d), carbofuran (98.7%, t₁/₂: 3.1 d) and metalaxyl (96.7%, t₁/₂: 3.8 d). Variations in the treatment conditions including addition of the antibiotic oxytetracycline and co-bioaugmentation with a bacterial consortium did not significantly affect the removal performance of the biomixture. Bacterial and fungal community profiles determined by DGGE analyses revealed changes that responded to biomixture aging, and not to antibiotic or pesticide addition. The proposed biomixture exhibits very efficient elimination during simultaneous pesticide application; moreover, the matrix is highly stable during stressful conditions such as the co-application of antibiotics of agricultural use.
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