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Plant-beneficial elements status assessment in soil-plant system in the vicinity of a chemical industry complex: shedding light on forage grass safety issues Full text
2015
Anjum, Naser A. | Duarte, Armando C. | Pereira, Eduarda | Aḥmad, Iqbāl
Plant-beneficial elements status assessment in soil-plant system in the vicinity of a chemical industry complex: shedding light on forage grass safety issues Full text
2015
Anjum, Naser A. | Duarte, Armando C. | Pereira, Eduarda | Aḥmad, Iqbāl
Human health is closely linked with soils via plants, grazers, or plant-based products. This study estimated plant-beneficial elements (macronutrients: K, P; secondary macronutrients: Ca, Mg; micronutrients: Mo, Mn, Na, Ni, Se) in both soils and shoots of two forage grass species (Eriophorum angustifolium and Lolium perenne) prevalent in the vicinity of a chemical industry complex (Estarreja, Portugal). Both soils and plants from the chemical industrial areas exhibited differential concentrations of the studied elements. In soils, the role of contamination was evidenced as insignificant in context of its impact on all the tested macro and secondary macronutrients except P, and micronutrients such as Mo and Ni. In forage grass plant shoots, the role of contamination was evidenced as insignificant in relation to its impact on all the tested macro and secondary macronutrients except K. Between the two forage grass plants, high Se-harboring L. perenne cannot be recommended for its use as animal feed.
Show more [+] Less [-]Plant-beneficial elements status assessment in soil-plant system in the vicinity of a chemical industry complex: shedding light on forage grass safety issues Full text
2015 | 1000
Anjum, Naser A. | Duarte, Armando C. | Pereira, Eduarda | Ahmad, Iqbal
Human health is closely linked with soils via plants, grazers, or plant-based products. This study estimated plantbeneficial elements (macronutrients: K, P; secondary macronutrients: Ca, Mg; micronutrients: Mo, Mn, Na, Ni, Se) in both soils and shoots of two forage grass species (Eriophorum angustifolium and Lolium perenne) prevalent in the vicinity of a chemical industry complex (Estarreja, Portugal). Both soils and plants from the chemical industrial areas exhibited differential concentrations of the studied elements. In soils, the role of contamination was evidenced as insignificant in context of its impact on all the tested macro and secondary macronutrients except P, and micronutrients such asMo and Ni. In forage grass plant shoots, the role of contamination was evidenced as insignificant in relation to its impact on all the tested macro and secondary macronutrients except K. Between the two forage grass plants, high Se-harboring L. perenne cannot be recommended for its use as animal feed.
Show more [+] Less [-]Human health risk assessment of multiple contaminants due to consumption of animal-based foods available in the markets of Shanghai, China Full text
2015
Lei, Bingli | Zhang, Kaiqiong | An, Jing | Zhang, Xinyu | Yu, Yingxin
To assess the health risks due to food consumption, the human daily intake and uptake of organochlorine pesticides, polychlorinated biphenyls, polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, and toxic trace elements (mercury, chromium, cadmium, lead, and arsenic) were estimated based on the animal-based foods collected from markets in Shanghai, China. The estimated daily intake and uptake considering the contaminant bioaccessibility via single food consumption were 9.4–399 and 4.2–282 ng/kg body weight/day for adults, and 10.8–458 and 4.8–323 ng/kg body weight/day for children, respectively. These values were 0.2–104 and 0.05–58.1, and 0.2–119 and 0.06–66.6 ng/kg body weight/day via multiple food consumption for adults and children, respectively. According to the United States Environmental Protection Agency risk assessment method, the non-cancer and cancer health risks posed by the contaminants were estimated using the hazard quotient and the lifetime cancer risk method, respectively. The results showed that the combined hazard quotient values for multiple contaminants via single or multiple food consumption were below 1, suggesting that the residents in Shanghai would not experience a significant non-cancer health risk. Among the contaminants investigated, the potential non-cancer risk of methylmercury was highest. However, the combined cancer risk posed by multiple contaminants in most foods exceeded the accepted risk level of 10⁻⁶, and inorganic arsenic was the main contributor. The risks caused by polybrominated diphenyl ethers for cancer and non-cancer effects were negligible. The cancer risk of inorganic arsenic is a matter of concern in animal-based foods from Shanghai markets.
Show more [+] Less [-]Simultaneous detection of imidacloprid and parathion by the dual-labeled time-resolved fluoroimmunoassay Full text
2015
Shi, Haiyan | Sheng, Enze | Feng, Lu | Zhou, Liangliang | Hua, Xiude | Wang, Minghua
A highly sensitive direct dual-labeled time-resolved fluoroimmunoassay (TRFIA) to detect parathion and imidacloprid simultaneously in food and environmental matrices was developed. Europium (Eu³⁺) and samarium (Sm³⁺) were used as fluorescent labels by coupling separately with L₁-Ab and A₁P₁-Ab. Under optimal assay conditions, the half-maximal inhibition concentration (IC₅₀) and limit of detection (LOD, IC₁₀) were 10.87 and 0.025 μg/L for parathion and 7.08 and 0.028 μg/L for imidacloprid, respectively. The cross-reactivities (CR) were negligible except for methyl-parathion (42.4 %) and imidaclothiz (103.4 %). The average recoveries of imidacloprid ranged from 78.9 to 104.2 % in water, soil, rice, tomato, and Chinese cabbage with a relative standard deviation (RSD) of 2.4 to 11.6 %, and those of parathion were from 81.5 to 110.9 % with the RSD of 3.2 to 10.5 %. The results of TRFIA for the authentic samples were validated by comparison with gas chromatography (GC) analyses, and satisfactory correlations (parathion: R ² = 0.9918; imidacloprid: R ² = 0.9908) were obtained. The results indicate that the dual-labeled TRFIA is convenient and reliable to detect parathion and imidacloprid simultaneously in food and environmental matrices.
Show more [+] Less [-]Does financial development reduce environmental degradation? Evidence from a panel study of 129 countries Full text
2015
Al-mulali, Usama | Tang, Chor Foon | Ozturk, Ilhan
The purpose of this study is to explore the effect of financial development on CO₂ emission in 129 countries classified by the income level. A panel CO₂ emission model using urbanisation, GDP growth, trade openness, petroleum consumption and financial development variables that are major determinants of CO₂ emission was constructed for the 1980–2011 period. The results revealed that the variables are cointegrated based on the Pedroni cointegration test. The dynamic ordinary least squares (OLS) and the Granger causality test results also show that financial development can improve environmental quality in the short run and long run due to its negative effect on CO₂ emission. The rest of the determinants, especially petroleum consumption, are determined to be the major source of environmental damage in most of the income group countries. Based on the results obtained, the investigated countries should provide banking loans to projects and investments that can promote energy savings, energy efficiency and renewable energy to help these countries reduce environmental damage in both the short and long run.
Show more [+] Less [-]Optimal nano-descriptors as translators of eclectic data into prediction of the cell membrane damage by means of nano metal-oxides Full text
2015
Toropova, Alla P. | Toropov, Andrey A. | Benfenati, Emilio | Korenstein, Rafi | Leszczynska, Danuta | Leszczyński, Jerzy
Systematization of knowledge on nanomaterials has become a necessity with the fast growth of applications of these species. Building up predictive models that describe properties (both beneficial and hazardous) of nanomaterials is vital for computational sciences. Classic quantitative structure– property/activity relationships (QSPR/QSAR) are not suitable for investigating nanomaterials because of the complexity of their molecular architecture. However, some characteristics such as size, concentration, and exposure time can influence endpoints (beneficial or hazardous) related to nanoparticles and they can therefore be involved in building a model. Application of the optimal descriptors calculated with the so-called correlation weights of various concentrations and different exposure times are suggested in order to build up a predictive model for cell membrane damage caused by a series of nano metal-oxides. The numerical data on correlation weights are calculated by the Monte Carlo method. The obtained results are in good agreement with the experimental data.
Show more [+] Less [-]Efficient degradation of trichloroethylene in water using persulfate activated by reduced graphene oxide-iron nanocomposite Full text
2015
Ahmad, Ayyaz | Gu, Xiaogang | Li, Li | Lv, Shuguang | Xu, Yisheng | Guo, Xuhong
Graphene oxide (GO) and nano-sized zero-valent iron-reduced graphene oxide (nZVI-rGO) composite were prepared. The GO and nZVI-rGO composite were characterized by transmission electron microscopy (TEM), Fourier transform infrared (FTIR), energy-dispersive spectroscopy (EDS), and Raman spectroscopy. The size of nZVI was about 6 nm as observed by TEM. The system of nZVI-rGO and persulfate (PS) was used for the degradation of trichloroethylene (TCE) in water, and showed 26.5 % more efficiency as compared to nZVI/PS system. The different parameters were studied to determine the efficiency of nZVI-rGO to activate the PS system for the TCE degradation. By increasing the PS amount, TCE removal was also improved while no obvious effect was observed by varying the catalyst loading. Degradation was decreased as the TCE initial concentration was increased from 20 to 100 mg/L. Moreover, when initial solution pH was increased, efficiency deteriorated to 80 %. Bicarbonate showed more negative effect on TCE removal among the solution matrix. To better understand the effects of radical species in the system, the scavenger tests were performed. The •SO₄ ⁻ and •O₂ ⁻ were predominant species responsible for TCE removal. The nZVI-rGO-activated PS process shows potential applications in remediation of highly toxic organic contaminants such as TCE present in the groundwater. Graphical abstract Persulfate activated by reduced graphene oxide and nano-sized zero-valent iron composite can be used for efficient degradation of trichloroethylene (TCE) in water.
Show more [+] Less [-]Subcellular distribution and chemical forms of cadmium in a dark septate endophyte (DSE), Exophiala pisciphila Full text
2015
Zhan, Fangdong | He, Yongmei | Li, Yuan | Li, Tao | Yang, Yun-Ya | Toor, Gurpal S. | Zhao, Zhiwei
Our objective was to understand the cadmium (Cd) tolerance mechanisms by investigating the subcellular distribution, chemical forms of Cd and adsorptive groups in the mycelia of Exophiala pisciphila. We grew E. pisciphila in the liquid media with increasing Cd concentrations (0, 25, 50, 100, 200, and 400 mg L⁻¹). Increased Cd in the media caused a proportional increase in the Cd uptake by E. pisciphila. Subcellular distribution indicated that 81 to 97 % of Cd was associated with the cell walls. The largest amount and proportion (45–86 %) of Cd was extracted with 2 % acetic acid, and a concentration-dependent extraction was observed, both of which suggest that Cd-phosphate complexes were the major chemical form in E. pisciphila. A large distribution of phosphate and Cd on the mycelia surface was observed by scanning electron microscopy-energy dispersive spectrometer (SEM-EDS). The precipitates associated with the mycelia were observed to contain Cd by transmission electron microscopy-energy dispersive X-ray spectroscopy (TEM-EDX). Fourier transform infrared (FTIR) identified that hydroxyl, amine, carboxyl, and phosphate groups were responsible for binding Cd. We conclude that Cd associated with cell walls and integrated with phosphate might be responsible for the tolerance of E. pisciphila to Cd.
Show more [+] Less [-]The application of advanced oxidation technologies to the treatment of effluents from the pulp and paper industry: a review Full text
2015
Hermosilla, Daphne | Merayo, Noemí | Gasco Sidro, Antonio J. (Antonio José) | Blanco, Angeles
The paper industry is adopting zero liquid effluent technologies to reduce freshwater use and meet environmental regulations, which implies closure of water circuits and the progressive accumulation of pollutants that must be removed before water reuse and final wastewater discharge. The traditional water treatment technologies that are used in paper mills (such as dissolved air flotation or biological treatment) are not able to remove recalcitrant contaminants. Therefore, advanced water treatment technologies, such as advanced oxidation processes (AOPs), are being included in industrial wastewater treatment chains aiming to either improve water biodegradability or its final quality. A comprehensive review of the current state of the art regarding the use of AOPs for the treatment of the organic load of effluents from the paper industry is herein addressed considering mature and emerging treatments for a sustainable water use in this sector. Wastewater composition, which is highly dependent on the raw materials being used in the mills, the selected AOP itself, and its combination with other technologies, will determine the viability of the treatment. In general, all AOPs have been reported to achieve good organic removal efficiencies (COD removal >40 %, and about an extra 20 % if AOPs are combined with biological stages). Particularly, ozonation has been the most extensively reported and successfully implemented AOP at an industrial scale for effluent treatment or reuse within pulp and paper mills, although Fenton processes (photo-Fenton particularly) have actually addressed better oxidative results (COD removal ≈ 65–75 %) at a lab scale, but still need further development at a large scale.
Show more [+] Less [-]Effects of mountain beaver management and thinning on 15-year-old Douglas fir growth and survival Full text
2015
Campbell, Dan L. | Engeman, Richard M. | Farley, James P.
We examined 4-year growth of 15-year-old damaged and undamaged Douglas fir (Pseudotsuga menzesii) after integrating temporary population reductions of mountain beaver (Aplodontia rufa) with thinning in a pre-commercial hand-planted plantation in western Washington. Five treatment combinations were considered: (1) trapping mountain beavers in an unthinned area, (2) trapping before thinning to 65 trees/ha (160 trees/ac), (3) no trapping and thinning to 65 trees/ha, (4) no trapping and thinning to 146 trees/ha (360 trees/ac), and (5) no trapping and no thinning. Removal of ≥90 % of mountain beavers temporarily reduced mountain beaver activity whether the stand was unthinned or thinned. Diameter growth at breast height (dbh) was greater for undamaged trees than for damaged trees in thinned areas. Tree height growth was greatest in trapped areas whether thinned or not. No differences were detected in 4-year survival between trees damaged aboveground and those without aboveground damage, which may be related to undetected root damage to trees without aboveground damage. Basal diameter growth and dbh growth were greatest for areas thinned to 65 trees/ha. Seventy-eight percent of stomachs from mountain beaver trapped in winter contained Douglas fir root or stem materials. Overall, short-term removal of mountain beavers integrated with pre-commercial thinning promoted growth of crop trees.
Show more [+] Less [-]Distribution of P, K, Ca, Mg, Cd, Cu, Fe, Mn, Pb and Zn in wood and bark age classes of willows and poplars used for phytoextraction on soils contaminated by risk elements Full text
2015
Zárubová, Pavla | Hejcman, Michal | Vondráčková, Stanislava | Mrnka, Libor | Száková, Jiřina | Tlustoš, Pavel
Fast-growing clones of Salix and Populus have been studied for remediation of soils contaminated by risk elements (RE) using short-rotation coppice plantations. Our aim was to assess biomass yield and distributions of elements in wood and bark of highly productive willow (S1—[Salix schwerinii × Salix viminalis] × S. viminalis, S2—Salix × smithiana clone S-218) and poplar (P1–Populus maximowiczii × Populus nigra, P2—P. nigra) clones with respect to aging. The field experiment was established in April 2008 on moderately Cd-, Pb- and Zn- contaminated soil. Shoots were harvested after four seasons (February 2012) and separated into annual classes of wood and bark. All tested clones grew on contaminated soils, with highest biomass production and lowest mortality exhibited by P1 and S2. Concentrations of elements, with exception of Ca and Pb, decreased with age and were higher in bark than in wood. The Salix clones were characterised by higher removal of Cd, Mn and Zn compared to the Populus clones. Despite generally higher RE content in young shoots, partly due to lower wood/bark ratios and higher RE concentrations in bark, the overall removal of RE was higher in older wood classes due to higher biomass yield. Thus, longer rotations seem to be more effective when phytoextraction strategy is considered. Of the four selected clones, S1 exhibited the best removal of Cd and Zn and is a good candidate for phytoextraction.
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