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1.
Removal of Cu, Zn, and Cd from aqueous solutions by the dairy manure-derived biochar 总被引:15,自引:0,他引:15
Xiaoyun Xu Xinde Cao Ling Zhao Hailong Wang Hongran Yu Bin Gao 《Environmental science and pollution research international》2013,20(1):358-368
Purpose
Biochar derived from waste biomass is now gaining much attention for its function as a biosorbent for environmental remediation. The objective of this study was to determine the effectiveness of biochar as a sorbent in removing Cd, Cu, and Zn from aqueous solutions.Methods
Biochar was produced from dairy manure (DM) at two temperatures: 200°C and 350°C, referred to as DM200 and DM350, respectively. The obtained biochars were then equilibrated with 0–5 mM Cu, Zn or Cd in 0.01 M NaNO3 solution for 10 h. The changes in solution metal concentrations after sorption were evaluated for sorption capacity using isotherm modeling and chemical speciation Visual MINTEQ modeling, while the solid was collected for species characterization using infrared spectroscopy and X-ray elemental dot mapping techniques.Results
The isotherms of Cu, Zn, and Cd sorption by DM200 were better fitted to Langmuir model, whereas Freundlich model well described the sorption of the three metals by DM350. The DM350 were more effective in sorbing all three metals than DM200 with both biochars had the highest affinity for Cu, followed by Zn and Cd. The maximum sorption capacities of Cu, Zn, and Cd by DM200 were 48.4, 31.6, and 31.9 mg g?1, respectively, and those of Cu, Zn, and Cd by DM350 were 54.4, 32.8, and 51.4 mg g?1, respectively. Sorption of the metals by the biochar was mainly attributed to their precipitation with PO 4 3? or CO 3 2? originating in biochar, with less to the surface complexation through –OH groups or delocalized π electrons. At the initial metal concentration of 5 mM, 80–100 % of Cu, Zn, and Cd retention by DM200 resulted from the precipitation, with less than 20 % from surface adsorption through phenonic –OH complexation. Among the precipitation, 20–30 % of the precipitation occurred as metal phosphate and 70–80 % as metal carbonate. For DM350, 75–100 % of Cu, Zn, and Cd retention were due to the precipitation, with less than 25 % to surface adsorption through complexation of heavy metal by phenonic –OH site or delocalized π electrons. Among the precipitation, only less than 10 % of the precipitation was present as metal phosphate and more than 90 % as metal carbonate.Conclusions
Results indicated that dairy manure waste can be converted into value-added biochar as a sorbent for sorption of heavy metals, and the mineral components originated in the biochar play an important role in the biochar's high sorption capacity. 相似文献2.
Acker CI Souza AC Dos Santos MP Mazzanti CM Nogueira CW 《Environmental science and pollution research international》2012,19(8):3481-3490
Purpose
In this study, we investigated the effect of diphenyl diselenide [(PhSe)2] on chlorpyrifos (CPF)-induced hepatic and hematologic toxicity in rats.Methods
Rats were pre-treated with (PhSe)2 (5?mg/kg) via the oral route (oral gavage) once a day for 7?days. On the eighth and ninth days, rats were treated with (PhSe)2 (5?mg/kg) 30?min prior to CPF (50?mg/kg, by subcutaneous route). The aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase activities were determined in plasma of rats. Lipid peroxidation, protein carbonyl, and non-protein thiol levels as well as catalase, superoxide dismutase, glutathione peroxidase, glutathione reductase, and gluthatione S-transferase activities were determined in livers of rats. Hematological parameters were also determined.Results
The results showed that CPF caused hepatic oxidative damage, as demonstrated by an increase in lipid peroxidation and protein carbonyl levels which was associated with a decrease in antioxidant defenses. CPF exposure caused a reduction in the leukocyte, indicating hematologic toxicity. (PhSe)2 was effective in attenuating these toxic effects caused by CPF exposure in rats.Conclusions
The results indicated that (PhSe)2 was effective in protecting the hepatic and hematologic toxicity induced by acute CPF exposure in rats. 相似文献3.
Talano MA Busso DC Paisio CE González PS Purro SA Medina MI Agostini E 《Environmental science and pollution research international》2012,19(6):2202-2211
Introduction
Transgenic plant strategies based on peroxidase expression or overexpression would be useful for phenolic compound removal since these enzymes play an important role in phenolic polymerizing reactions.Material and methods
Thus, double transgenic (DT) plants for basic peroxidases were obtained and characterized in order to compare the tolerance and efficiency for 2,4-dichlorophenol (2,4-DCP) removal with WT and simple transgenic plants expressing TPX1 or TPX2 gene. Several DT plants showed the expression of both transgenes and proteins, as well as increased peroxidase activity.Results
DT lines showed higher tolerance to 2,4-DCP at early stage of development since their germination index was higher than that of WT seedlings exposed to 25?mg/L of the pollutant. High 2,4-DCP removal efficiencies were found for WT tobacco plants. TPX1 transgenic plants and DT (line d) reached slightly higher removal efficiencies for 10?mg/L of 2,4-DCP than WT plants, while DT plants (line A) showed the highest removal efficiencies (98%). These plants showed an increase of 21% and 14% in 2,4-DCP removal efficiency for solutions containing 10 and 25?mg/L 2,4-DCP, respectively, compared with WT plants. In addition, an almost complete toxicity reduction of postremoval solutions using WT and DT plants was obtained through AMPHITOX test, which indicates that the 2,4-DCP degradation products would be similar for both plants.Conclusion
These results are relevant in the field of phytoremediation application and, moreover, they highlight the safety of using DT tobacco plants because nontoxic products were formed after an efficient 2,4-DCP removal. 相似文献4.
Catarino AI Bauwens M Dubois P 《Environmental science and pollution research international》2012,19(6):2344-2353
Purpose
In order to better understand if the metabolic responses of echinoids could be related to their acid?Cbase status in an ocean acidification context, we studied the response of an intertidal sea urchin species, Paracentrotus lividus, submitted to low pH at two different temperatures.Methods
Individuals were submitted to control (8.0) and low pH (7.7 and 7.4) at 10°C and 16°C (19?days). The relation between the coelomic fluid acid?Cbase status, the RNA/DNA ratio of gonads and the individual oxygen uptake were studied.Results
The coelomic fluid pH decreased with the aquarium seawater, independently of temperature, but this explained only 13% of the pH variation. The coelomic fluid showed though a partial buffer capacity that was not related to skeleton dissolution ([Mg2+] and [Ca2+] did not differ between pH treatments). There was an interaction between temperature and pH on the oxygen uptake (V O2) which was increased at pH?7.7 and 7.4 at 10°C in comparison with controls, but not at 16°C, indicating an upregulation of the metabolism at low temperature and pH. However, gonad RNA/DNA ratios did not differ according to pH and temperature treatments, indicating that even if maintenance of physiological activities has an elevated metabolic cost when individuals are exposed to stress, they are not directly affected during short-term exposure. Long-term studies are needed in order to verify if gonad production/growth will be affected by low pH seawaters exposure. 相似文献5.
Lithner D Nordensvan I Dave G 《Environmental science and pollution research international》2012,19(5):1763-1772
Purpose
The large global production of plastics and their presence everywhere in the society and the environment create a need for assessing chemical hazards and risks associated with plastic products. The aims of this study were to determine and compare the toxicity of leachates from plastic products made of five plastics types and to identify the class of compounds that is causing the toxicity.Methods
Selected plastic types were those with the largest global annual production, that is, polypropylene, polyethylene, and polyvinyl chloride (PVC), or those composed of hazardous monomers (e.g., PVC, acrylonitrile?Cbutadiene?Cstyrene [ABS], and epoxy). Altogether 26 plastic products were leached in deionized water (3?days at 50°C), and the water phases were tested for acute toxicity to Daphnia magna. Initial Toxicity Identification Evaluations (C18 filtration and EDTA addition) were performed on six leachates.Results
For eleven leachates (42%) 48-h EC50s (i.e the concentration that causes effect in 50 percent of the test organisms) were below the highest test concentration, 250 g plastic/L. All leachates from plasticized PVC (5/5) and epoxy (5/5) products were toxic (48-h EC50s ranging from 2 to 235?g plastic/L). None of the leachates from polypropylene (5/5), ABS (5/5), and rigid PVC (1/1) products showed toxicity, but one of the five tested HDPE leachates was toxic (48-h EC50 17?C24?g plastic/L). Toxicity Identification Evaluations indicated that mainly hydrophobic organics were causing the toxicity and that metals were the main cause for one leachate (metal release was also confirmed by chemical analysis).Conclusions
Toxic chemicals leached even during the short-term leaching in water, mainly from plasticized PVC and epoxy products. 相似文献6.
A tiered ecological risk assessment of three chlorophenols in Chinese surface waters 总被引:1,自引:0,他引:1
Jin X Gao J Zha J Xu Y Wang Z Giesy JP Richardson KL 《Environmental science and pollution research international》2012,19(5):1544-1554
Introduction
The ecological risks posed by three chlorophenols (CPs), 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TCP), and pentachlorophenol (PCP) in Chinese surface waters were assessed.Materials and methods
This was achieved by applying a tiered ecological risk assessment (ERA) approach ranging from deterministic methods to probabilistic options to measured concentrations of CPs in surface water of seven major watersheds and three drainage regions in China and the chronic toxicity data for indigenous Chinese species.Results and discussion
The results show that the risks of three chlorophenols are ranked PCP>2,4-DCP??2,4,6-TCP. PCP posed little ecological risk while 2,4-DCP and 2,4,6-TCP posed negligible or de minimis risk in Chinese surface water. However, the risks varied with different river basins, for example, PCP posed some ecological risk in the Yangtze, Huaihe, and Pearl Rivers. The magnitude of 2,4-DCP and 2,4,6-TCP pollution in North China was more serious than that in South China.Conclusion
The probabilistic risk assessment approach, which can provide more information for risk managers and decision makers, was favored over the screening-level single-value estimate method. However, the results from all tiers of the ERA methods in the framework were consistent with each other. 相似文献7.
Testolin RC Tischer V Lima AO Cotelle S Férard JF Radetski CM 《Environmental science and pollution research international》2012,19(6):2186-2194
Background, aim and scope
Agrochemicals could reach aquatic ecosystems and damage ecosystem functionality. Natural formicide could be an alternative to use in comparison with the more toxic formicides available on the market. Thus, the objective of this study was to assess the ecotoxicity of the new natural formicide Macex? with a battery of classical aquatic ecotoxicity tests.Material and methods
Bacteria (Aliivibrio fischeri), algae (Pseudokirchneriella subcapitata), hydra (Hydra attenuata), daphnids (Daphnia magna), and fish (Danio rerio) tests were performed in accordance with international standardized methodologies.Results
In the range of formicide concentrations tested (0.03 to 2.0?g?L?1) EC50 values varied from 0.49 to >2.0?g?L?1, with P. subcapitata being the most sensitive species and H. attenuata and D. rerio the most tolerant species to this product in aqueous solutions.Conclusions
This new formicide preparation can be classed as a product of low toxicity compared to the aquatic ecotoxicity of the most common commercialized formicides. 相似文献8.
S Uno A Shintoyo E Kokushi M Yamamoto K Nakayama J Koyama 《Environmental science and pollution research international》2011,19(7):2595-2605
Purpose
We evaluate malathion toxicity to Japanese medaka (Oryzias latipes) juveniles by using a mass spectrometry combined with gas chromatography (GC/MS) metabolomics approach.Methods
Medaka were exposed to low (L) and high (H) concentrations (nominally 20 and 2,000 ??g/L, respectively) of water-borne malathion. Metabolites were extracted from the fish, derivatized, and analyzed by GC/MS. Identified metabolites were subjected to one-way analysis of variance and principal component analysis (PCA). We examined the variations in the amounts of the metabolites during the exposure period.Results and discussion
At 24 h, control, L, and H groups were separated along PC1, suggesting that the effects of malathion depended on exposure concentration. The PCA results at 96 h suggest that the metabolite profiles variations of the L and H groups differed, and thus that the effects of malathion in groups differed. At 24 h, the amounts of amino acids in both exposed groups were lower than the control group amounts, perhaps owing to accelerated protein synthesis. At 96 h, the amounts of almost all the amino acids increased in the L group but decreased in the H group relative to the control group amounts, suggesting the proteolysis occurred in the L group while protein synthesis continued in the H group, that the high malathion exposure affected the fish. In addition, at 96 h, gluconeogenesis may have been induced in the L group but not in H group.Conclusions
Malathion exposure may have altered the balance between protein synthesis and degradation and induced gluconeogenesis in medaka. Our results suggest that metabolomics will be useful for comprehensive evaluation of toxicity. 相似文献9.
Syakti AD Asia L Kanzari F Umasangadji H Malleret L Ternois Y Mille G Doumenq P 《Environmental science and pollution research international》2012,19(5):1524-1535
Introduction
The future ??Calanque National Park?? coastlines of the Bouches-du-Rh?ne and Var departments in France, constitute one of the ten biodiversity hot spots identified in the Mediterranean basin that receives industrial and urban wastewaters discharged from Marseille and its suburbs.Materials and methods
Organochlorine pesticides (OCs) and polychlorinated biphenyls (PCBs) were measured in sediments collected from 12 sampling sites (C1?CC12) of sewage discharge to the sea from the wastewater treatment plant of Cortiou-Marseille. This study aims to determine the extent of these compounds in the sediments and to establish the possible sources of these contaminants.Results and discussion
Total pesticides in the sediments ranged from 1.2 to 190.6 ng g-1 dry weight of sediment. The highest value was found at station C1, with a decreasing trend in total OC concentrations seaward. Among these compounds, the concentrations of the sum of dichlorodiphenyltrichloroethane (??DDT) were the highest, ranging from 0.7 to 114.3 ng g-1. PCB concentrations, expressed as equivalent to Arochlor 1260, varied from 9.1 to 226.9 ng g-1. Individually, the dominant coplanar PCB congeners CB-153, CB-138 and CB-101. Generally, PCB concentrations at stations C2, C3, C5 and C7 were higher than those at stations C10, C11 and C12. Through some pollution indices, we showed the long-term contamination input of these OCs (DDT, endosulfan, HCH and heptachlor cases) rather than a recent release resulting from degradation and long-term weathering (dieldrin, aldrin and methoxychlor cases). Occurrence of PCBs might be due to their resistance to degradation processes or/and chronic inputs.Conclusions
By comparison with available sediment quality guideline (SQG) values, the environmental significance and toxicological implications of PCBs and OCs (i) reveal the probable adverse effects for the sediments from C1, C5, C6, C9 and (ii) confirm the adverse effect for marine biota and more particularly for benthic communities at C2?CC4, C7 and C8. 相似文献10.
Inmaculada Riba López Judit Kalman Carlos Vale Julián Blasco 《Environmental science and pollution research international》2010,17(9):1519-1528
Background, aim and scope
The influence of pH (range 6.5–8.5) on the uptake of Zn, Cd, Pb, Cu, Ni, Cr, Hg, and As by juveniles of the clam Ruditapes philippinarum was examined in order to understand whether variation in sediment pH has significant repercussions on metal bioaccumulation.Materials and methods
Clams were exposed to sediments collected in three locations in the Gulf of Cadiz (Huelva, Guadalquivir and Bay of Cadiz) and to contaminated particles derived from an accidental mining spill in Spain.Results
With a notable exception of metal Cd, the concentration of metals within clams significantly increased (p?<?0.1) when sediment pH was lowered by one or two units. Moreover, the magnitude of this effect was dependent on the type of sediment contamination.Discussion
Lower pH increases metal solubility and reduces or invert the metal sorption of metals to sediments. Increases in free metal ions in water favors metal uptake by clams, hence pH is an important factor controlling the mobility of these metals within sediments and their subsequent bioaccumulation within biota. Although sediment-water exchange of Cd can increase with acidification, this excess may be counterbalanced by the presence of ligands in seawater preventing the uptake by organism. Besides chlorines, Cd has also an affinity with carbonates and other ligands present in sea water. These Cd-carbonate complexes may reduce the bioavailable to organisms.Conclusions
These results highlight the potential implications of sediment acidification, either due to the storage excess of organic matter or to the forced capture of CO2, on the increasing metal availability to benthic organisms.Recommendations and perspectives
This kind of studies should be increased to address the influence of acidification in the behavior, bioavailability, toxicity, and risk assessment of contaminants associated with sediments either above sub-seabed geological formations in marine environments or in high enriched by organic matter in estuarine areas. Recently, the capture of CO2 in marine environments has been approved and started; it is necessary to address the potential impacts associated with leakages or other events occurring during the procedure of injection and storage of CO2. 相似文献11.
Steven J. Wearne Martin G. de M. Gem Nigel Harrison Peter P. Collier Frank Fairweather Michael Fielding Andrew Franklin James R. Startin Roger J. Tregunno Heather Walton 《Environmental science and pollution research international》1996,3(2):83-88
A scheme has been developed to rank 70 industrial organic chemicals in order of their priority for further study as potential contaminants of food. Numerical scales were developed for the following seven key criteria concerning environmental issues, food and toxicity: -Production volume -Pattern of usage -Possible fate in the environment -Likelihood of chemical entering the food chain -Mechanism of entry into the food chain -Persistence and accumulation in the food chain -Toxicity. Each chemical was assigned a score for the above criteria, which were combined to give an overall ranking for the chemicals. This scheme has been endorsed by the MAFF Steering Group on Chemical Aspects of Food Surveillance. It will be used in the assessment of relative priorities for further non-statutory surveillance for these contaminants in the UK food supply. 相似文献
12.
Materazzi S Canepari S Aquili S 《Environmental science and pollution research international》2012,19(8):3292-3298
Introduction
The copper bioaccumulation by the floating Lemna minor and by the completely submerged Ranunculus tricophyllus as a function of exposure time and copper concentration was studied, with the aim of proposing these species as environmental biosensors of the water pollution.Results
The results show that both these aquatic angiosperms are good indicators of copper pollution because the copper uptake is the only function of metal concentration (water pollution).Conclusion
Uptake behavior is reported as a function of the time and concentration, based on the results of a 3-year study. Kinetic evaluations are proposed. 相似文献13.
Tobias Frische Michael Faust Wiebke Meyer Thomas Backhaus 《Environmental science and pollution research international》2009,16(5):593-603
Background, aim and scope
Estrogenic and non-estrogenic chemicals typically co-occur in the environment. Interference by non-estrogenic chemicals may confound the assessment of the actual estrogenic activity of complex environmental samples. The aim of the present study was to investigate whether, in which way and how seriously the estrogenic activity of single estrogens and the observed and predicted joint action of estrogenic mixtures is influenced by toxic masking and synergistic modulation caused by non-estrogenic chemical confounders.Materials and methods
The yeast estrogen screen (YES) was adapted so that toxicity and estrogenicity could be quantified simultaneously in one experimental run. Mercury, two organic solvents (dimethyl sulfoxide (DMSO) and 2,4-dinitroaniline), a surfactant (LAS-12) and the antibiotic cycloheximide were selected as toxic but non-estrogenic test chemicals. The confounding impact of selected concentrations of these toxicants on the estrogenic activity of the hormone 17ß-estradiol was determined by co-incubation experiments. In a second step, the impact of toxic masking and synergistic modulation on the predictability of the joint action of 17ß-estradiol, estrone and estriol mixtures by concentration addition was analysed.Results
Each of the non-estrogenic chemicals reduced the apparent estrogenicity of both single estrogens and their mixtures if applied at high, toxic concentrations. Besides this common pattern, a highly substance- and concentration-dependent impact of the non-estrogenic toxicants was observable. The activity of 17ß-estradiol was still reduced in the presence of only low or non-toxic concentrations of 2,4-dinitroaniline and cycloheximide, which was not the case for mercury and DMSO. A clear synergistic modulation, i.e. an enhanced estrogenic activity, was induced by the presence of slightly toxic concentrations of LAS-12. The joint estrogenic activity of the mixture of estrogens was affected by toxic masking and synergistic modulation in direct proportion to the single estrogens, which allowed for an adequate adaptation of concentration addition and thus unaffected predictability of the joint estrogenicity in the presence of non-estrogenic confounders.Discussion
The modified YES proved to be a reliable system for the simultaneous quantification of yeast toxicity and estrogen receptor activation. Experimental results substantiate the available evidence for toxic masking as a relevant phenomenon in estrogenicity assessment of complex environmental samples. Synergistic modulation of estrogenic activity by non-estrogenic confounders might be of lower importance. The concept of concentration addition is discussed as a valuable tool for estrogenicity assessment of complex mixtures, with deviations of the measured joint estrogenicity from predictions indicating the need for refined analyses.Conclusions
Two major challenges are to be considered simultaneously for a reliable analysis of the estrogenic activity of complex mixtures: the identification of known and suspected estrogenic compounds in the sample as well as the substance- and effect-level-dependent confounding impact of non-estrogenic toxicants.Recommendations and perspectives
The application of screening assays such as the YES to complex mixtures should be accompanied by measures that safeguard against false negative results which may be caused by non-estrogenic but toxic confounders. Simultaneous assessments of estrogenicity and toxicity are generally advisable. 相似文献14.
Dongo K Tiembré I Koné BA Zurbrügg C Odermatt P Tanner M Zinsstag J Cissé G 《Environmental science and pollution research international》2012,19(8):3192-3199
Introduction
On August 2006, a cargo ship illegally dumped 500?t of toxic waste containing high concentrations of hydrogen sulphide in numerous sites across Abidjan. Thousands of people became ill. Seventeen deaths were associated with toxic waste exposure.Materials and methods
This study reports on environmental and health problems associated with the incident. A cross-sectional transect study was conducted in five waste dumping site areas.Results
Of the households, 62.1% (n?=?502) were exposed to the effects of the pollutants and 51.1% of the interviewed people (n?=?2,368) in these households showed signs of poisoning. Most important symptoms were cough (37.1%), asthenia (33.1%), pruritus (29.9%) and nausea (29.1%).Discussion
The health effects showed different frequencies in the five waste impact sites. Among the poisoned persons, 21.1% (n?=?532) presented symptoms on the survey day (i.e., 4?months after incident). Transect sampling allowed to determine a radius of vulnerability to exposure of up to 3?km from the point of toxic waste disposal.Conclusion
The area of higher vulnerability is influenced by various environmental factors, such as size and severity of pollution site, duration of toxic waste pollution on the impact site and locally climatic conditions. The surveillance of effects on environment and human health is warranted to monitor the development. 相似文献15.
Purpose
We analyzed and compared the distributions of 13 target pharmaceuticals in different water samples from the Hangzhou metropolitan area and Linan County, Southeast China.Methods
Sampling was conducted in five hospitals, two wastewater treatment plants (WWTPs), and Qiantang River. Samples were concentrated by solid-phase extraction and PPCP concentrations were determined by UPLC-MS/MS.Results and discussion
Trimethoprim, erythromycin A dihydrate, norfloxacin, ofloxacin, diclofenac sodium, and atenolol were the most frequently detected pharmaceuticals in hospital effluents. Most of the pharmaceutical concentrations in hospital effluents were higher than those in the WWTP influents. Although both WWTPs adopt the anaerobic?Caerobic?Canoxic treatment process, the removal rates for pharmaceuticals, such as trimethoprim and diclofenac sodium, were completely different. Meanwhile, erythromycin A dihydrate, ofloxacin, penicillin-G, cephalexin, cefazolin, ibuprofen, and diclofenac sodium were detected in Qiantang River.Conclusions
These results indicate that hospitals are more concentrated sources of pharmaceuticals than WWTPs, and the WWTPs are not the only route of entry of pharmaceuticals into aquatic environments in these two regions. 相似文献16.
Peuravuori J 《Environmental science and pollution research international》2012,19(6):2259-2270
Purpose
This study contains some new findings connected to the photolysis of the drug paracetamol (hereinafter APAP) especially in light of estimating natural conditions, and it will offer information to better evaluate environmental problems connected with this widely used analgesic agent. Only a few studies, so far, have focussed on the photodegradation process of APAP in the natural environment, and the question about the role of the colored/chromophoric dissolved organic matter (CDOM) and nitrate (NO 3 ? ) as photoinductors is almost open.Methods
APAP dissolved in freshwater and pure laboratory water in the presence and absence of CDOM and NO 3 ? ions was irradiated using weak-energy photon energies simulating natural conditions.Results
CDOM and NO 3 ? as photoinductors produced only the slow phototransformation of APAP under weak energy radiation, and APAP seemed to be practically resistant to direct photolysis under weak radiant energies available in natural conditions. The estimated reaction efficiencies, in addition to half-lives, speak for that NO 3 ? and CDOM do not act as quite independent photoinductors but their effect in conjunction (CDOM?CNO 3 ? ?Cwater) is stronger than the separate ones. The principal phototransformation intermediates of APAP were mono-hydroxy derivatives, depending on available photon energies formed via ortho- or meta-hydroxylation, possessing substantial power of resistance to further specific transformation reactions.Conclusions
The estimated half-life of the phototransformation of APAP in the natural aqueous environment and in the presence of suitable photoinductors will be about 30?days or more. 相似文献17.
Oukarroum A Polchtchikov S Perreault F Popovic R 《Environmental science and pollution research international》2012,19(5):1755-1762
Purpose
In this study, the effect of silver nanoparticles (AgNPs) on the photosynthetic performance of two green algae, Chlorella vulgaris and Dunaliella tertiolecta, was investigated at 25°C and 31°C.Methods
To induce AgNPs effect, algal cells were exposed for 24?h to concentrations varying from 0 to 10?mg/L. The polyphasic OJIP fluorescence transient was used to evaluate photosystem II (PSII).Results
We show that growth media and temperature had different effects in AgNPs agglomerates formation and Zeta potential. When temperature conditions change, inhibitory effect of AgNPs also undergoes changes. Increase of temperature induced higher altering effects to PSII quantum yield, primary photosynthetic electron transport, and consequently higher decrease of total photosynthetic performance if compared to AgNPs effect alone. AgNPs has a negative effect on D. tertiolecta compared to C. vulgaris.Conclusion
We conclude that temperature tends to enhance the toxic effects on aquatic alga and these alterations might have serious consequences on ecosystem equilibrium and aquatic plant communities. 相似文献18.
Alka Dhondge Subin Surendran Muhil Vannan Seralathan Pravin K. Naoghare Kannan Krishnamurthi Sivanesan Saravana Devi Tapan Chakrabarti 《Environmental science and pollution research international》2012,19(9):4030-4041
Purpose
There are many arguments on the carcinogenic potential of bitumen extract. The mechanism of bitumen-induced damage is not well understood at the molecular level. Therefore, in the present study, cell-transforming and tumor-inducing potential of bitumen extract was studied using in vitro [human osteosarcoma (HOS) cells] and in vivo [nude and severe combined immunodeficiency (SCID) mice] models.Methods
Gas chromatography/mass spectrometry (GC/MS) analysis was carried out to find out the existence of carcinogenic compounds in the bitumen extract. Cell transformation test, anchorage independence assay, karyotyping assay, tumorigenicity assay, and 2-DE analysis were used to find out the effect of bitumen using the in vitro and in vivo models.Results
GC/MS analysis showed the existence of carcinogenic compounds in the bitumen extract. HOS cells were treated with different concentrations (25, 50, and 100???l/ml) of bitumen extract. Compared to the parental HOS cells, bitumen transformants (HOS T1 and HOS T2) showed the characteristics of anchorage independency, chromosomal anomaly, and cellular transformation. Interestingly, bitumen transformants were not able to form tumor in nude/SCID mice. Proteomic analysis revealed the existence of 19 differentially expressed proteins involved in progression of cancer, angiogenesis, cell adhesion, etc.Conclusions
Exposure of bitumen extract to HOS cells results in the cellular transformation similar to cancer cells and can modulate proteins involved in the progression of cancer. We state that the non-tumorogenic potential of bitumen transformant in nude/SCID mice can be attributed to the downregulation of galectin-1, chromodomain helicase DNA-binding protein 1-like gene, and membrane-associated guanylate kinase 2 protein. 相似文献19.
Xu L Chen X Chen J Zhang F He C Du K Wang Y 《Environmental science and pollution research international》2012,19(5):1443-1453
Background
PM10 aerosol samples were simultaneously collected at two urban and one urban background sites in Fuzhou city during two sampling campaigns in summer and winter. PM10 mass concentrations and chemical compositions were determined.Methods
Water-soluble inorganic ions (Cl?, NO 3 ? , SO 4 2? , NH 4 + , K+, Na+, Ca2+, and Mg2+), carbonaceous species (elemental carbon and organic carbon), and elements (Al, Si, Mg, K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Se, Br, and Pb) were detected using ion chromatography, thermal/optical reflectance, and proton-induced X-ray emission methods, respectively.Results
PM10 mass concentrations, as well as most of the chemical components, were significantly increased from urban background to urban sites, which were due to enhanced anthropogenic activities in urban areas. Elements, carbonaceous species, and most of the ions were more uniformly distributed at different types of sites in winter, whereas secondary ion SO 4 2? , NO 3 ? , and NH 4 + showed more evident urban-background contrast in this season. The chemical mass closure indicated that mineral dust, organic matters, and sulfate were the most abundant components in PM10. The sum of individually measured components accounted for 86.9?C97.7% of the total measured PM10 concentration, and the discrepancy was larger in urban area than in urban background area.Conclusion
According to the principal component analysis?Cmultivariate linear regression model, mineral dust, secondary inorganic ions, sea salt, and motor vehicle were mainly responsible for the PM10 particles in Fuzhou atmosphere, and contributed 19.9%, 53.3%, 21.3%, and 5.5% of PM10, respectively. 相似文献20.
Microbial structure and chemical components of aerosols caused by rotating brushes in a wastewater treatment plant 总被引:1,自引:0,他引:1
Yunping Han Lin Li Junxin Liu Mengzhu Zhang 《Environmental science and pollution research international》2012,19(9):4097-4108