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Changes in chemical forms, subcellular distribution, and thiol compounds involved in Pb accumulation and detoxification in Athyrium wardii (Hook.)
2015
Zhao, Li | Li, Tingxuan | Yu, Haiying | Chen, Guangdeng | Zhang, Xizhou | Zheng, Zicheng | Li, Jinxing
Athyrium wardii is one of the dominant plant species flourishing on the Pb–Zn mine tailings in Sichuan Province, China. A greenhouse pot experiment was conducted to evaluate the chemical forms, subcellular distribution, and thiol compounds in A. wardii under different Pb treatments. The results showed that plants of the mining ecotype (ME) of A. wardii were more tolerant to Pb than those of the non-mining ecotype (NME) in spite of accumulation of higher Pb concentrations. The Pb concentrations in shoots and roots of the ME were 3.2∼8.6 times and 3.0∼24.6 times higher than those of the NME, respectively. The ME was more efficient in Pb uptake than the NME. Moreover, 27.8∼39.0 % of the total Pb in ME was sodium chloride (NaCl) extractable and 38.0∼48.5 % was acetic acid (HAc) extractable, whereas only a minority of total Pb was in ethanol and H₂O extractable. In subcellular level, 77.4∼88.8 % of total Pb was stored in the cell walls of ME and 9.0∼18.9 % in soluble fractions. Increasing Pb concentrations enhanced sequestration of Pb into the cell walls and soluble fractions of ME tissues to protect organelles against Pb. Synthesis of non-protein thiols (NP-SH) and phytochelatins (PCs) in roots of ME significantly enhanced in response to Pb stress, and significant increases in glutathione (GSH) were observed in shoots of ME. Higher levels of NP-SH, GSH, and PCs were observed in roots of the ME comparing with NME, especially under high Pb treatments. The results indicated that Pb was localized mainly in cell wall and soluble fraction of ME plants with low biological activity by cell wall deposition and vacuolar compartmentalization, which might be the important adapted Pb detoxification mechanisms of ME.
显示更多 [+] 显示较少 [-]Assessment of dermal absorption of DEET-containing insect repellent and oxybenzone-containing sunscreen using human urinary metabolites
2015
Yiin, Lih-Ming | Tian, Jia-Ni | Hung, Chien-Che
Mutual enhancement of dermal absorption of N,N-diethyl-m-toluamide (DEET) and oxybenzone (OBZ) has been reported recently with DEET and OBZ being active ingredients of insect repellent and sunscreen, respectively. To assess the reported enhancing effect directly, we used human urinary metabolites as biomarkers; besides, we also sought to determine the best way for concurrent use of these two products without extra absorption of either. Four dermal application methods were used: DEET only (S1), OBZ only (S2), DEET on top of OBZ (S3), and OBZ on top of DEET (S4). Among the study methods, there was a significant difference (p = 0.013), which was attributed to the difference between S1 and S4, suggesting that applying OBZ over DEET on the skin lead to significantly higher absorption of DEET. Using both products in reverse order, (S3) did not result in extra DEET absorption significantly. As for OBZ permeation, no significant difference was observed among the methods. In summary, the enhancement of DEET absorption is confirmed for OBZ being applied over DEET on the skin; should concurrent use of both be necessary, applying sunscreen (OBZ) first and then insect repellent (DEET) with a 15-min interval is recommended.
显示更多 [+] 显示较少 [-]Acute toxicity and sublethal effects of gallic and pelargonic acids on the zebrafish Danio rerio
2015
Techer, Didier | Milla, Sylvain | Fontaine, Pascal | Viot, Sandrine | Thomas, Marielle
Gallic and pelargonic acids are naturally found in a variety of plants and food products. Despite their extensive use in man-made applications, little is known regarding their potential risks to aquatic vertebrates. The aim of this work was to assess the acute toxicity of these polyphenolic and fatty acid compounds to the zebrafish. In order to get insights into sublethal effects, the enzyme activity of usual biomarkers related to oxidative stress and biotransformation were also assessed in fish. These latter included total superoxide dismutase, catalase as well as total glutathione peroxidase for antioxidant defence mechanisms and glutathione S-transferase for biotransformation related enzyme. Gallic acid was practically non-toxic (96-h lethal concentration (LC₅₀) > 100 mg/L) whereas pelargonic acid was slightly toxic (96-h LC₅₀of 81.2 mg/L). Moreover, biomarker analyses indicated enhanced superoxide dismutase activity in fish exposed to 20, 40 and 100 mg/L of gallic acid compared to control. A dose-dependent induction of glutathione peroxidase and glutathione S-transferase was reported following gallic acid exposure at the tested concentrations of 10, 20 and 40 mg/L, with the exception of 100 mg/L of substance where basal activity levels were reported. In the case of pelargonic acid, there was no change in antioxidant enzyme activity while an inhibition of glutathione S-transferase was observed from organisms exposed to 45, 58 and 76 mg/L of test solution. The results concerning sublethal effects on biological parameters of zebrafish highlighted thereby the need for further investigations following chronic exposure to both organic acids.
显示更多 [+] 显示较少 [-]Dynamics of microbiological parameters, enzymatic activities and worm biomass production during vermicomposting of effluent treatment plant sludge of bakery industry
2015
Yadav, Anoop | Suthar, S. | Garg, V. K.
This paper reports the changes in microbial parameters and enzymatic activities during vermicomposting of effluent treatment plant sludge (ETPS) of bakery industry spiked with cow dung (CD) by Eisenia fetida. Six vermibins containing different ratios of ETPS and CD were maintained under controlled laboratory conditions for 15 weeks. Total bacterial and total fungal count increased upto 7th week and declined afterward in all the bins. Maximum bacterial and fungal count was 31.6 CFU × 10⁶ g⁻¹ and 31 CFU × 10⁴ g⁻¹ in 7th week. Maximum dehydrogenase activity was 1921 μg TPF g⁻¹ h⁻¹ in 9th week in 100 % CD containing vermibin, whereas maximum urease activity was 1208 μg NH₄ ⁻N g⁻¹ h⁻¹ in 3rd week in 100 % CD containing vermibin. The enzyme activity and microbial counts were lesser in ETPS containing vermibins than control (100 % CD). The growth and fecundity of the worms in different vermibins were also investigated. The results showed that initially biomass and fecundity of the worms increased but decreased at the later stages due to non-availability of the palatable feed. This showed that quality and palatability of food directly affect biological parameters of the system.
显示更多 [+] 显示较少 [-]Copper uptake by Eichhornia crassipes exposed at high level concentrations
2015
Melignani, Eliana | de Cabo, Laura Isabel | Faggi, Ana María
The objective of this study was to assess the growth of water hyacinth (Eichhornia crassipes) and its ability to accumulate Cu from polluted water with high Cu concentrations and a mixture of other contaminants under short-term exposure, in order to use this species for the remediation of highly contaminated sites. Two hydroponic experiments were performed under greenhouse conditions for 7 days. One of them consisted of growing water hyacinth in Hoagland solution supplemented with 15 or 25 mg Cu/L and a control. The other one contained water hyacinth growing in polluted river water supplemented with 15 mg Cu/L and a control. Cu was accumulated principally in roots. The maximum Cu concentration was 23,387.2 mg/kg dw in the treatment of 25 mg Cu/L in Hoagland solution. Cu translocation from roots to leaves was low. The mixture of 15 mg Cu/L with polluted water did not appear to have toxic effects on the water hyacinth. This plant showed a remarkable uptake capacity under elevated Cu concentrations in a mixture of pollutants similar to pure industrial effluents in a short time of exposure. This result has not been reported before, to our knowledge. This species is suitable for phytoremediation of waters subject to discharge of mixed industrial effluents containing elevated Cu concentrations (≥15 mg Cu/L), as well as nutrient-rich domestic wastewaters.
显示更多 [+] 显示较少 [-]Effect of exposure to O3, NO 2, and SO 2 on chronic obstructive pulmonary disease hospitalizations in Tabriz, Iran
2015
Ghozikali, Mohammad Ghanbari | Mosaferi, Mohammad | Safari, Gholam Hossein | Jaafari, Jalil
Air pollution in cities is a serious environmental problem especially in the developing countries. We examined the associations between gaseous pollutants and hospitalizations for chronic obstructive pulmonary diseases (COPD) among people living in Tabriz, a city in north western of Iran. We used the approach proposed by the World Health Organization (WHO) using the AirQ 2.2.3 software developed by the WHO European Center for Environment and Health, Bilthoven Division. To assess human exposure and health effect, data were used for ozone as a1h average; for nitrogen dioxide and sulfur dioxide as daily average concentrations. The association between air pollution and chronic obstructive pulmonary disease (COPD) was assessed using AirQ 2.2.3 model. The results of this study showed that 3 % (95 % CI 1.2–4.8 %) of HA COPD were attributed to O₃concentrations over 10 μg/m³. Also, 0.9 % (95 % CI 0.1–2.2 %) and 0.4 % (95 % CI 0–1.1 %) of HA COPD were attributed to NO₂and SO₂concentrations over 10 μg/m³, respectively. For every 10 μg/m³increase in O₃, NO₂, and SO₂concentrations, the risk of HA COPD increase to about 0.58, 0.38, and 0.44 %, respectively. We found significant positive associations between the levels of all air pollution and hospital admissions COPD. Otherwise, O₃, NO₂, and SO₂have a significant impact on COPD hospitalization.
显示更多 [+] 显示较少 [-]An artificially constructed Syngonium podophyllum-Aspergillus niger combinate system for removal of uranium from wastewater
2015
He, Jia-dong | Wang, Yong-dong | Hu, Nan | Ding, Dexin | Sun, Jing | Deng, Qin-wen | Li, Chang-wu | Xu, Fei
Aspergillus niger was inoculated to the roots of five plants, and the Syngonium podophyllum-A. niger combinate system (SPANCS) was found to be the most effective in removing uranium from hydroponic liquid with initial uranium concentration of 5 mg L⁻¹. Furthermore, the hydroponic experiments on the removal of uranium from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L⁻¹ by the SPANCS were conducted, the inhibitory effect of A. niger on the growth of S. podophyllum in the SPANCS was studied, the accumulation characteristics of uranium by S. podophyllum in the SPANCS were analyzed, and the Fourier transform infrared (FT-IR) and extended X-ray absorption fine structure (EXAFS) spectra were measured. The results show that the removal of uranium by the SPANCS from the hydroponic liquids with initial uranium concentrations of 0.5, 1.0, and 3.0 mg L⁻¹ reached 98.20, 97.90, and 98.50 %, respectively, after 37 days of accumulation of uranium; that the uranium concentrations in the hydroponic liquids decreased to 0.009, 0.021, and 0.045 mg L⁻¹, respectively, which are lower than the stipulated concentration for discharge of 0.050 mg L⁻¹ by the People’s Republic of China; that A. niger helped to generate more groups in the root of S. podophyllum which can improve the complexing capability of S. podophyllum for uranium; and that the uranium accumulated in the root of S. podophyllum was in the form of phosphate uranyl and carboxylic uranyl.
显示更多 [+] 显示较少 [-]Alkylphenol ethoxylates and brominated flame retardants in water, fish (carp) and sediment samples from the Vaal River, South Africa
2015
Chokwe, T. B. | Okonkwo, J. O. | Sibali, L. L. | Ncube, E. J.
Alkylphenol ethoxylates (APEs) and brominated flame retardants (BFRs) are known to be bio-accumulative, persistent, and endocrine disruptors and can cause adverse health effects in animals and humans. In this study, environmental samples were collected from sites along the Vaal River, South Africa in order to determine the concentrations of APEs and BFRs in water, sediment, and fish samples. The highest concentrations of these pollutants were observed from discharge of the Rietspruit WWTW. Measurable levels of both APEs and BFRs were observed with APEs exhibiting higher concentrations than BFRs in all the matrices. The concentrations observed for APEs and BFRs were as follows: 1.00–3.85 μg/L APEs, 0.09–0.26 μg/L PBDEs, ND- 0.14 PBBs and 0.51–1.77 μg/L HBCD for water samples; 47–63 ng/g lipid APEs, 3.24–12.4 ng/g lipid PBB, 4.63–33 ng/g lipid PBDEs and 10–13 ng/g lipid HBCD for fish; and 40–184 ng/g (wet weight (ww)) APEs, 2.93–5.9 ng/g (ww) PBB, 10–24 ng/g (ww) PBDEs, and 15–52 ng/g (ww) HBCD for sediment samples. The concentrations of APEs and BFRs in water samples were found to be in the range with the results reported in the literature while the concentration in fish and sediment were lower than the concentrations reported in other studies.
显示更多 [+] 显示较少 [-]Role of transpiration in arsenic accumulation of hyperaccumulator Pteris vittata L
2015
Wan, Xiao-ming | Lei, Mei | Chen, Tong-bin | Yang, Jun-xing | Liu, Hong-tao | Chen, Yang
Mechanisms of Pteris vittata L. to hyperaccumulate arsenic (As), especially the efficient translocation of As from rhizoids to fronds, are not clear yet. The present study aims to investigate the role of transpiration in the accumulation of As from the aspects of transpiration regulation and ecotypic difference. Results showed that As accumulation of P. vittata increased proportionally with an increase in the As exposure concentration. Lowering the transpiration rate by 28∼67 % decreased the shoot As concentration by 19∼56 %. Comparison of As distribution under normal treatment and shade treatment indicated that transpiration determines the distribution pattern of As in pinnae. In terms of the ecotypic difference, the P. vittata ecotype from moister and warmer habitat had 40 % higher transpiration and correspondingly 40 % higher shoot As concentration than the ecotype from drier and cooler habitat. Results disclosed that transpiration is the main driver for P. vittata to accumulate and re-distribute As in pinnae.
显示更多 [+] 显示较少 [-]Evaluation of an eventual ecotoxicity induced by textile effluents using a battery of biotests
2015
Bedoui, Ahmed | Tigini, Valeria | Ghedira, Kamel | Varese, Giovanna Cristina | Chekir Ghedira, Leila
Textile industry is considered as one of the important factors of the economic growth in Tunisia. However, this prominent role has certainly some drawbacks mainly represented by the huge amounts of textile wastewaters generated that become a real menace to nature. Many previous studies showed the purifying potential of some activated sludge and bacteria (Pseudomonas putida) to decolourize textile effluents. However, in many cases, decolourization of wastewaters is not necessary associated with detoxification, generating a real risk for the ecosystem in general. We evaluated in this work the induced toxicity of a textile effluent before and after its treatment with activated sludge followed by P. putida, using a battery of biotests. This study proved the detoxifying power of the activated sludge according to most of ecotoxicity tests. The treatment with P. putida did not improve the quality of the effluent; on the contrary, it could increase its toxicity. Daphnia magna and Raphidocelis subcapitata appear to be the most sensitive organisms in assessing eventual toxicity caused by this kind of wastewaters.
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