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1.
J Hazard Mater ; 389: 121891, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-31882338

RESUMO

The potentially high release of estrogens to surface waters due to high population density and local livestock production in the Beijing-Tianjin-Hebei region may pose adverse effects on reproductive systems of aquatic organisms. This study found that total measured concentrations of estrone (E1), 17ß-estradiol (E2), estriol (E3), 17α-ethinylestradiol (EE2) and diethylstilbestrol (DES) were 468 ± 27 ng/L in treated wastewater and 219 ± 23 ng/L in river waters in this region. E2, E3 and EE2 were the predominant estrogens in river waters. The restriction of DES for human use should have been enforced, however concentrations of DES were relatively high compared to other studies. Haihe and Yongdingxin Rivers delivered approximately 1.8 tonnes of estrogens to the Bohai Bay annually. Concentrations of individual estrogens were significantly higher in river waters in the dry season, however, mass loadings were significantly higher in the wet season. The average E2-equivalent concentrations reached 1.2 ± 0.2 and 0.64 ± 0.08 µg-E2/L following long-term and short-term exposure estimates, respectively, in river waters with an EE2 contribution of over 90 %. This could give rise to high risks to fish. Estrogens in river waters largely derived from human excretion. Field studies on estrogenic effects on fish reproductive systems are required locally considering high estrogen contamination levels.


Assuntos
Estrogênios/análise , Águas Residuárias/análise , Poluentes Químicos da Água/análise , Animais , China , Monitoramento Ambiental , Estrogênios/toxicidade , Peixes , Medição de Risco , Rios , Águas Residuárias/toxicidade , Poluentes Químicos da Água/toxicidade
2.
Environ Int ; 130: 104919, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31226562

RESUMO

Concentrations of widely used antibiotics were predicted to be the highest in the Haihe River Catchment across China previously, potentially resulting in high ecotoxicological risks in this region. As a result of growing usage and regulation of antibiotic use in animals, the pattern of use may have altered temporally for different antibiotics. It is important to monitor the occurrence of antibiotics within different categories for understanding their mass loading to the catchment and the potential ecotoxicological risks involved. This study investigated the seasonal occurrence and spatial variation of 15 antibiotics in the Haihe River Catchment during 2016-2017. The investigated compounds included veterinary antibiotics, human-use antibiotics, and those intended for both human and animal use. Measurements reported from previous studies were compared with the results of this study and indicated that the use of veterinary antibiotics is probably increasing around the catchment. The ∑antibiotics concentration (i.e. the summed concentration of the 15 target antibiotics) ranged from 414 to 1951 ng/L, with an average of 821 ng/L. Discharges from wastewater treatment plants were the main sources of these compounds. The mass loading of antibiotics to the river waters was higher during wet seasons than during dry seasons. The mass fluxes of the antibiotics continuously increased towards the lower reaches of the rivers. The total annual input of the antibiotics from the Haihe River and Yongdingxin River into the Bohai Bay was 5008 kg/yr. Ofloxacin, trimethoprim, leucomycin, anhydro erythromycin and florfenicol were the predominant antibiotics, whilst amoxicillin, anhydro erythromycin, ofloxacin, norfloxacin and enrofloxacin may pose high ecotoxicological risks to the investigated aquatic ecosystem. Several antibiotics selected in this study were reported for the first time in this catchment. This study provides important information for chemical management and indicates that further monitoring is needed on the more harmful and veterinary antibiotics in the catchment.


Assuntos
Antibacterianos/análise , Monitoramento Ambiental , Rios/química , Poluentes Químicos da Água/análise , China , Ecotoxicologia , Medição de Risco , Estações do Ano , Águas Residuárias/análise
3.
Huan Jing Ke Xue ; 37(10): 3806-3812, 2016 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-29964412

RESUMO

This study investigated the ability of ultra violet-visible (UV-Visible) spectroscopy to analyze the origin,compositions,structure and humification level of dissolved organic matter(DOM). Seven surface water samples were collected from the Benxi City section of mainstream in Taizi River. Nine indices (SUVA254, E2/E3, E2/E4, E4/E6, S275-295, S350-400, A2/A1, A3/A1 and A3/A2), deduced from elemental analysis and UV visible spectroscopy of DOM, were used to assess the humification degree. The results showed that the characteristics of DOM were distributed along urban river and industrial wastewater discharge, and the DOM of waste water from Benxi steel plant contained a low degree of condensation of small organic molecules. E2/E3 showed positive correlation with E2/E4, and negative correlations with S275-295, S350-400, A2/A1,indicating that humification degree of DOM was not only concerned with the degree of condensation of organic molecules, but also closely associated with the ratio between humic acid and fulvic acid. Composition structure of DOM showed significant positive correlations with A2/A1, SUVA254 and S275-295, and significant negative correlations with E2/E3 and E2/E4. Based on the loadings of DOM component and scores plot of sampling sites in Taizi River (Benxi City section),the characteristics of DOM were distinctly distributed along urban river and industrial wastewater discharge, proving that the river was deeply influenced by human activity.

4.
Huan Jing Ke Xue ; 30(10): 2918-23, 2009 Oct 15.
Artigo em Chinês | MEDLINE | ID: mdl-19968107

RESUMO

Although dinoflagellates have been used to assess biological toxicity of contaminants, this method still lacks of corresponding toxicity assessment standard. This study appraised the toxicity of selected heavy metals to dinoflagellates based on the dinoflagellates bioluminescence with QwikLite developed by the United States Navy. The results show that single heavy metal biological toxicity is in the order: Hg2+ > Cu2+ > Cd2+ > As5+ > Pb2+ > Cr6+; Two, three and four heavy metal mixture experiments show synergism primarily, antagonism is in minority. pH has not remarkable effect on dinoflagellates, they can be applied directly in natural water, but pH influence Hg2+ and Cu2+ toxicity greatly, eliminating the influence of pH is essential when doing these two kind of ions measurements. The nutrients has little influence on dinoflagellates, change in COD has obvious effect on the response relationships between dinoflagellates and Hg2+ or CU2+. Metal toxicity assessment using dinoflagellates shows great sensitivity, narrow response scope and high stability. Dinoflagellates are good species for heavy metal biological toxicity test in aquatic system.


Assuntos
Dinoflagellida/efeitos dos fármacos , Monitoramento Ambiental/métodos , Medições Luminescentes , Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Dinoflagellida/metabolismo , Metais Pesados/análise , Medição de Risco/métodos , Testes de Toxicidade/métodos , Poluentes Químicos da Água/análise
5.
Huan Jing Ke Xue ; 30(7): 2099-104, 2009 Jul 15.
Artigo em Chinês | MEDLINE | ID: mdl-19775015

RESUMO

With pJP4 plasmid carrying genetic engineering bacteria Pseudomonas putida SM1443 :: gfp2x (pJP4 :: dsRed) as the donor, horizontal gene transfer of pJP4 plasmid in 4 isolated pure strains was investigated, and effects of the donor bacteria inoculation on the removal of the target pollutant 2,4-dichlorophenoxyacetic acid (2,4-D) was studied through conducting gene augmentation in activated sludge, biofilm, aerobic granular sludge and river sediment system, respectively. Results showed that plasmid pJP4 could transfer from Pseudomonas putida SM1443 to a broad spectrum of bacteria. Inoculation of pJP4 plasmid carrying donor bacterium apparently promoted the degradation of 2,4-D for all the above four systems. For the activated sludge system (2,4-D initial concentration at 450 mg/L), 66% and 54% removal of 2,4-D was achieved after 143.5 h reaction for the gene augmented and control system, respectively. For the biofilm system with 2,4-D initial concentration at 180 mg/L, 2,4-D removal percentage at 113 h was 99% and 61%, respectively. For aerobic granular sludge system (2,4-D initial concentration at 160 mg/L), 2,4-D was nearly completely removed by 62 h in the gene-augmented system, while the control system only degraded 26% at 66 h. For the system with sediment (2,4-D initial concentration at 2 mg/L), 93% and 69% removal of 2,4-D was obtained at 344 h reaction for the gene augmented and control system, respectively. Confocal laser scanning microscopy (CLSM) analysis revealed the formation and presence of transconjugants in different gene augmentation systems.


Assuntos
Ácido 2,4-Diclorofenoxiacético/metabolismo , Conjugação Genética , Engenharia Genética , Plasmídeos/genética , Pseudomonas putida/genética , Ácido 2,4-Diclorofenoxiacético/isolamento & purificação , Bactérias/genética , Bactérias/metabolismo , Biodegradação Ambiental , Transferência Genética Horizontal , Microbiologia Industrial , Reação em Cadeia da Polimerase , Pseudomonas putida/metabolismo , Esgotos/microbiologia , Eliminação de Resíduos Líquidos/métodos
6.
Huan Jing Ke Xue ; 30(6): 1855-9, 2009 Jun 15.
Artigo em Chinês | MEDLINE | ID: mdl-19662880

RESUMO

The objective of this study was to investigate the release and transform Pb from the CRT glass following its entrance into the soil environment. A long-term incubation of soil mixed with CRT glass particles and sequential selective dissolution technology were used. Results indicated that the addition of CRT glass particle to the soil led to the increase in the total concentration of Pb in the soil from 28.4 mg/kg to 8 634.4 mg/kg. In details,the concentrations of Pb in the soluble and exchangeable form (EXC-Pb) and bound to the carbonate minerals (CARB-Pb) and manganese and iron oxides (RO-Pb) were 0.20-0.98 mg/kg, 20.1-103.6 mg/kg, and 26.7-54.3 mg/kg, respectively. The sum of these three fractions of Pb was 48.6-155.2 mg/kg. In the EXC, CARB, and RO dissolution steps, the concentrations of Pb directly released from the surface of the CRT glass particles were only (0.038 +/- 0.025), (7.55 +/- 3.13), (7.55 +/- 3.13) mg/kg, respectively. Hence, the released Pb from the CRT glass was mostly bound to the carbonate minerals and manganese and iron oxides in the soil. The decrease of pH from 8.0-8.3 to 7.1-7.5 did not significantly affect the chemical forms of Pb in the soil. The release rates of Pb from the CRT glass to the EXC, CARB, and RO forms were 0.15/t, 21.1/t, and 3.8/t mg x (kg x d)(-1), respectively (t is incubation time in unit of d). The CARB-Pb or RO-Pb might transform to EXC-Pb when pH or Eh of soil decreases, thus entrance of CRT glass particles in the soil environment may pose an ecological risk.


Assuntos
Tubo de Raio Catódico , Chumbo/análise , Eliminação de Resíduos/métodos , Poluentes do Solo/análise , Vidro/análise
7.
Huan Jing Ke Xue ; 30(3): 663-7, 2009 Mar 15.
Artigo em Chinês | MEDLINE | ID: mdl-19432309

RESUMO

With the development of point pollution control, non-point source pollution has become an important environmental and water quality management problem. Land cover composition across a watershed is a dominant factor in controlling the amount of nitrogen and phosphorus exported from a watershed. Generally, urban and agricultural land covers are considered as principal sources of excess loads of nitrogen (N) and phosphorous (P) in receiving waters. A well developed literature of nutrient export coefficients by land-cover class was used to model the risk of equaling or exceeding specified levels of nutrient export in drainage basin of Dahuofang Reservoir. The model was applied to about 513 comparatively small watersheds mapped for the drainage basin of Dahuofang Reservoir for environmental analysis and planning. The results suggest that the probabilities of risk are 19.31% and 8.95% for N and P nutrient respectively. As the spatial distribution concerned, risk estimates generally differed with different slope degrees and districts. Risk estimates generally increased from the places where lies near the rivers to the places where are far from the river, but numerous areas of high variability were evident.


Assuntos
Produtos Agrícolas/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Nitrogênio/análise , Fósforo/análise , Poluentes Químicos da Água/análise , China , Água Doce/análise , Medição de Risco , Rios
8.
Huan Jing Ke Xue ; 30(12): 3494-501, 2009 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-20187377

RESUMO

The Daliaohe river system in China has been seriously affected by long-term intensive industrial, urban and agricultural activities. The objective of this study was to determine the total phosphorus (TP) content and forms of phosphate in the sediments and investigate geochemical relationships between P forms and mineral matrix elements and P bioavailability. Four sediment profiles were taken in the Daliaohe river systems. TP content in the sediment was measured by ICP-OES and chemical forms of phosphate were measured by sequential selective extraction method. Results indicated that TP ranged from 323 to 2619 mg x kg(-1). In the sediments except 25-47 cm depth of sediment profile in the Hun river, the content of Ca bound P (Ca-P) was the highest, with more than 40% of TP. The contents of Fe bound P (Fe-P) and residual P (RES-P) were 15% to 25% of TP, while the contents of reductant soluble P (RS-P) and Al bound P (Al-P) were generally 5% to 10% of TP. However, the content of soluble and loosely bound P (S/L-P) was only less than 0.5% of TP. Huge accumulation of P in the 25-47 cm depth of the sediment profile in the Hun river led to a bigger increase in the contents of Fe-P and Al-P than Ca-P, where Al-P, Fe-P and Ca-P contents were 6.2%-23.4%, 19.6%-34.1% and 14.6%-35.6% of TP, respectively. Correlation analysis showed that sum of Fe-P and RS-P, Ca-P, and RES-P were positively correlated to Fe, Ca, and sediment organic matter (SOM) contents, respectively in the sediments except the 25-47 cm depth of sediment profile in the Hun river. In addition, TP content was positively correlated to Fe and SOM contents. The molar ratios of Fe to TP generally ranged from 20.9 to 33.9, indicating that most of sediments have capability to further retain P. Potential bioavailable P (BAP) including S/L-P, Al-P and Fe-P in the sediments was 85.43 to 1830.5 mg x kg(-1), and this part of phosphorus might pose a potential risk to the eutrophication of the Daliaohe river system and its estuary.


Assuntos
Água Doce/análise , Sedimentos Geológicos/análise , Fósforo/química , Poluentes Químicos da Água/química , China , Monitoramento Ambiental , Fosfatos/análise , Fósforo/análise , Rios , Poluentes Químicos da Água/análise
9.
Huan Jing Ke Xue ; 29(8): 2123-30, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18839560

RESUMO

Geochemical behavior of major and trace elements in the sediment of the Songhua River was studied. 39 bottom sediment samples were collected from the Songhua River and total contents of As, Cd, Co, Cr, Cu, Hg, Zn, Ni, Pb, Sb, Sc, V, Mn, Ti, Al, Fe, Mg, Ca, Na and K in these samples were measured. The objectives of this study were to identify the contents and spatial variations of these metals in the sediment, investigate geochemical relationships among the elements, and develop baseline relationships between 9 trace metals and conservative reference element Sc to quantify the contamination of these 9 elements. Results indicated that the concentrations of toxic trace metals, such as As, Cd, Co, Cr, Cu, Hg, Zn, Ni, Pb, and V in the sediment, were 2.7-11.5, 0.05-1.38, 4.8-14.7, 15.9-78.9, 2.4-75.4, 0.01-1.27, 21.8-403.1, 6.2-35.8, 12.6-124.4, and 22.1-108.0 mg/kg, respectively. Due to the input of anthropogenic sources, temporal and spatial variation of Cd, Cu, Hg, Zn, and Pb contents in the sediment was higher than that of major elements. In addition, correlations between these metals and their mineral matrix elements such as Fe, Mg, and Sc were decreased. The baseline relationships between general metal contaminants and Sc were developed, with high correlation coefficients for Co, Cr, Cu, Zn, Ni, Pb, and V and relatively low correlation coefficients for As and Cd. These baseline relationships provide a way to quantitatively evaluate the sediment contamination by these metals. Generally, sediment contamination of the Songhua River by trace metals was less than that of the Zhujiang River and the Changjiang River, and similar to that of the Huanghe River.


Assuntos
Água Doce/análise , Sedimentos Geológicos/química , Metais/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Água Doce/química , Geografia , Rios , Oligoelementos/análise
10.
Huan Jing Ke Xue ; 29(12): 3469-76, 2008 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-19256387

RESUMO

To understand the transport and bioavailability of heavy metals in the surface sediment of Daliao River system, nine samples of surface sediment were collected. Clay content, pH, and Eh of these sediment samples were measured. Total contents and chemical speciation of Cu, Pb, Zn and Ni in the sediment were determined. In addition, the concentrations of Cu, Pb, Zn and Ni in the pore water of the sediment were determined separately by DGT (diffusive gradient in thin film) method and traditional centrifuge method. The total contents of Cu, Pb, Zn and Ni in the sediment were 16.8-49.2, 12.9-55.8, 38.7-152.8 and 18.1-39.0 mg/kg, respectively. The ratios of DGT measured concentrations c (DGT) to heavy metal concentrations in pore water were lower than 0.5, showing lower replenishment of these metals from solid to the liquid and lower bioavailability of the metals in the sediments. Correlation analysis showed that c (DGT) of Cu was significantly influenced by Cu in the carbonate fraction (r = 0.633, p <0.05), while c (DGT) of Pb was influenced by Pb in the exchangeable fraction (r = 0.617, p <0.05). Ni in the exchangeable, Mn oxides, organic matter (OM) and Fe oxides fractions may contribute to the c (DGT) of Ni (r > 0.650, p <0.05). In addition, pH was also an important factor influencing the release of heavy metals from solid to liquid in sediments.


Assuntos
Água Doce/análise , Sedimentos Geológicos/química , Metais Pesados/análise , Poluentes Químicos da Água/análise , Disponibilidade Biológica , China , Cobre/análise , Monitoramento Ambiental , Chumbo/análise , Níquel/análise , Rios , Movimentos da Água , Zinco/análise
11.
Ying Yong Sheng Tai Xue Bao ; 18(7): 1523-7, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17886645

RESUMO

With gas chromatography-electron capture detector (GC-ECD), this paper analyzed 13 kinds of organochlorinae pesticides (OCP) in surface sediments collected from 22 sites of Song-Liao water system. The results showed that the total concentration of OCP varied from 3.06 to 23.24 ng x g(-1) in Daliao River system and from 4.26 to 18.45 ng x g(-1) in Songhuajiang River system. The most dominant OCP pollutant in the sediments in Song-Liao Watershed was HCH, but there existed different pollution tendency in the two subsystems. In Songhuajiang River, there were also relatively high concentrations of DDT. High concentration gamma-HCH was observed among the isomers of HCH in the whole watershed, which exceeded the initial affecting concentration and could potentially do toxic effect on the water creatures.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos Clorados/análise , Praguicidas/análise , Poluentes Químicos da Água/análise , China , DDT/análise , Monitoramento Ambiental/métodos , Hexaclorocicloexano/análise , Rios
12.
Ying Yong Sheng Tai Xue Bao ; 18(7): 1534-8, 2007 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-17886647

RESUMO

With GC/MS, a quantitative study was made on the polycyclic aromatic hydrocarbons (PAHs) in the surface water and suspended particulates in Daliao River system, with their spatial distribution and sources investigated. The results showed that the total PAHs concentration ranged from 946.1 to 13 448.5 ng x L(-1) in surface water, and from 317.5 to 238 518.7 ng x g in suspended particulates. The PAHs concentration was decreased in the order of Taizi River > Daliao River > Hunhe River. The PAHs in surface water were dominated by 3-5 rings, while those in suspended particulates were dominated by 2 rings. The calculated ratios of selected PAHs suggested that the discharges from municipal, petrochemical and steel industrial wastewater, and the atmospheric fallout might be the important PAHs sources, and the contamination sources of PAHs were the mixture of petrogenic and pyrolytic inputs. In comparing with other river and marine systems in the world, Daliao River system had higher concentrations of PAHs in its surface water and suspended particulates, and thus, presented certain ecological risk.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Rios , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental/métodos
13.
Huan Jing Ke Xue ; 28(3): 540-4, 2007 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-17633630

RESUMO

With benzene, naphthalene and biphenyl as the model aromatic hydrocarbon, the treatment of aromatic hydrocarbon containing wastewater by an anaerobic filter (AF) reactor operated in continuous mode and under denitrifying condition were conducted. With glucose as the supplemented carbon, the influence of C/N ratio on the degradation of organic compounds was also investigated. Results showed that the AF reactor could degrade these aromatic hydrocarbons effectively under above mentioned conditions. When the influent COD concentration was 1 000 mg/L, and benzene, naphthalene and biphenyl concentration was 60 mg/L, the removal efficiency for COD and aromatic hydrocarbons was 90% and 84%, respectively. Benzene was more easily degraded than naphthalene and biphenyl under denitrifying condition. When C/N was in the range 5 - 30, benzene removal percentage was always at about 90% , and C/N ratio did not have obvious effect on the degradation of benzene. The degradation of naphthalene and biphenyl and total COD was greatly influenced by C/N. When C/N was 15, the highest removal percentage was achieved and it was 90%, 78% and 82% for COD, naphthalene and biphenyl, respectively.


Assuntos
Bactérias Anaeróbias/metabolismo , Reatores Biológicos , Hidrocarbonetos Aromáticos/metabolismo , Nitrogênio/metabolismo , Eliminação de Resíduos Líquidos/métodos , Anaerobiose , Biodegradação Ambiental , Poluentes da Água/metabolismo
14.
Huan Jing Ke Xue ; 28(2): 261-6, 2007 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-17489180

RESUMO

Influence of microorganism for polycyclic aromatic hydrocarbons (PAHs) sorption on surface sediments and soils in Yellow River Delta was studied. The results indicated that phenanthrene and benzo[a]pyrene could be adsorbed or biodegraded by Bacillus subtilis, and 98% phenanthrene and 85% benzo[a]pyrene was eliminated by microorganism in adsorption process. Sorption isotherms of soils and sediments with and without microorganism were described by linear isotherm equation. Adsorption capacity of samples with microorganism increased about 35 times than that of without microorganism, but benzo[a] pyrene adsorption capacity decreased about 2/3. In desorption process, samples with microorganism desorbed less phenanthrene than without microorganism, but more benzo[a]pyrene. Microorganism plays an important role in adsorption process.


Assuntos
Sedimentos Geológicos/microbiologia , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Adsorção , Benzo(a)pireno/química , Benzo(a)pireno/metabolismo , Biodegradação Ambiental , Sedimentos Geológicos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Poluentes do Solo/química
15.
Huan Jing Ke Xue ; 28(12): 2750-7, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18290432

RESUMO

Three sediment cores were collected from the Daliao River system in May 2006. The physico-chemical characteristics and heavy metal contents of sediment cores were analyzed. The vertical profiles of metals in pore water were measured by diffusive gradient in thin films (DGT) and centrifugal methods separately. The sequence of the concentrations of Cd, Co, Cr and Cu in sediment is Cr > Cu > Co > Cd. The concentrations measured by DGT were lower than that measured by centrifugal method. The average ratios of DGT measured concentrations (cDGT) to the concentrations measured by centrifugal method of Cd, Co, Cr and Cu were 0.389, 0.328, 0.863 and 0.403, respectively. This suggested that the release rates of these metals from solid phase to solution followed the sequence of Cr > Cu > Cd > Co. The fluxes of Cd, Co Cr and Cu were 1.12 x 10(-7) - 3.28 x 10(-7) nmol/(cm2 x s), 2.48 x 10(-7) - 10.40 x 10(-7) nmol/(cm2 x s), 8.80 x 10(-6) - 12.65 x 10(-6) nmol/(cm2 x s) and 6.14 x 10(-6) - 13.93 x 10(-6) nmol/(cm2 x s), respectively. The result showed that the release of Cd and Cu was mainly influenced by organic matter (OM), while Fe oxides, Mn oxides and OM were major factors controlling the transfer of Cr. The redox potential may be the major factor influencing the release of Co element.


Assuntos
Monitoramento Ambiental/métodos , Água Doce/análise , Sedimentos Geológicos/análise , Metais Pesados/análise , Poluentes Químicos da Água/análise , Difusão , Monitoramento Ambiental/instrumentação , Sedimentos Geológicos/química , Oxirredução , Porosidade
16.
Huan Jing Ke Xue ; 27(9): 1738-43, 2006 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-17117625

RESUMO

Samples of water, suspended particulate matter (SPM) and sediment in the Yellow River was analyzed. The total concentration of PAHs in the main river varies from 179 ng/L to 369 ng/L (sigma 15PAHs) in water, from 54 microg/kg to 155 microg/kg (sigma 13PAHs) in SPM dry weight, and from 31 microg/kg to 133 microg/kg (sigma 13PAHs) dry weight in sediment. The levels of PAHs in water of tributaries are higher than those in the corresponding sites in the main river, and concentrations of benzo(a)pyrene in most of the stations sampled are above drinking water standard. In SPM, PAHs of 3 to 6 benzene rings are mainly correlated to the content of total organic carbon (TOC) in different sites of the main river, while only 4 to 6 rings PAHs in sediment of main river are correlated to TOC for the influence of Mengzhou Canal, whose concentration of 3-ring PAHs are quite high. The distribution of PAHs in all media sampled in the main river indicates that PAHs are mainly transported from water into SPM between Mengzhou and Jiaogong Bridge, while in the reach between Jiaogong bridge and Huayuankou a great reduce of PAHs in SPM is mainly due to the diluting effect in the interchanging process between sediment and SPM. Source analysis also reveals that PAHs are mainly originating from coal burning, although in some tributaries PAH inputs could come from combustion of petroleum.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Rios/química , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental , Sedimentos Geológicos/química , Resíduos Industriais
17.
Chemosphere ; 65(3): 365-74, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16580044

RESUMO

Samples of water, suspended particulate matter (SPM) and sediment were collected from mid- and down-stream of the Yellow River. The distribution and concentration of 10 nitroaromatic compounds and polychlorinated biphenyls (PCBs) were extensively studied. The total concentration of 10 nitrobenzenes (SigmaNBs) varied from 0.269 to 9.052 microg l(-1) in water, from 2.916 to 164.4 microg kg(-1) dry weight in SPM, and from 0.954 to 14.72 microg kg(-1) dry weight in sediment. PCBs associated with the sediments, measured as the summed responses of Aroclor 1242, 1248, 1254, 1260 (in comparison to those of a standard 1:1:1:1 mixture), were found to be in the range of non-detectable to 5.98 microg kg(-1). In the samples collected, various PCB congeners showed similar distribution characteristics with congeners containing 3-5 chlorine atoms accounting for more than 96.4% of total PCB. In most of the samples, PCB concentrations occurred in the order: TetraCB > TriCB > PentaCB. Levels of SigmaNBs in the Yellow River were relatively low in comparison with values reported from other river and marine systems, and PCB levels were comparatively low. Relative to the PCBs, SigmaNBs showed significantly more difference among the various stations, presumably due to the influence of different pollution sources. No obvious correlation was observed between the pollutant concentrations and either the TOC or the grain size of the sediments.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/química , Nitrobenzenos/análise , Bifenilos Policlorados/análise , Rios/química , Poluentes Químicos da Água/análise , China , Tamanho da Partícula
18.
Artigo em Inglês | MEDLINE | ID: mdl-12046654

RESUMO

The protein-binding forms of cadmium in polluted rice and wheat seeds and their stability were investigated using the methods of Sephadex chromatography. Three absorption peaks (F-I, F-II and F-III) were identified in Tris-HCl extraction of rice and wheat on Sephadex G 75. The Cd in the protein extracts from rice and wheat seeds was distributed mainly in the fractions of F-I and F-III. The apparent molecular weights of Cd-binding proteins for F-I and F-III were 54.5 and 5.5 KD, respectively. The components of amino acid for the protein bound with heavy metals were different. There were high contents of glutamic acid, cysteine, valine, isoleucine, leucine and tyrosine in the protein extracts of rice and wheat. After cooking, the Cd-binding proteins were destroyed. High molecular weight protein-binding form (54.5 KD) was broken into low molecular weight complex (5.5 KD) or tiny peptide chain. Simultaneously, Cd bound with protein was released, or mainly bound with protein of smaller molecular size. Enzyme treatment (pepsin and trypsin) also caused a destruction of Cd binding protein and a change in the distribution of Cd in the eluent. The concentrations of Cd in the elution of first and third peak decreased markedly, and the Cd distribution was observed in the elution after third peak (F-III).


Assuntos
Cádmio/química , Contaminação de Alimentos , Metalotioneína/química , Oryza/química , Triticum/química , Disponibilidade Biológica , Cádmio/análise , Culinária , Monitoramento Ambiental , Humanos , Peso Molecular , Sementes
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