Antibiotics have been used in animal feeding for long history.In recent years,much attention has been received for their negative effects on animal and human being as well.Technology has been focused on alternatives o...Antibiotics have been used in animal feeding for long history.In recent years,much attention has been received for their negative effects on animal and human being as well.Technology has been focused on alternatives of antibotics,such as probiotics,oligosaccharides,acidifiers,Chinese herds,chemical drugs,and other environmental measures.Their mechanism,effects,related factors and their prospect in the future were discussed in this paper.展开更多
Plant biosurfactants were used for the first time to remove As and co-existing metals from brownfield soils. Tannic acid （TA）, a polyphenol, and saponin （SAP）, a glycoside were tested. The soil washing experiments...Plant biosurfactants were used for the first time to remove As and co-existing metals from brownfield soils. Tannic acid （TA）, a polyphenol, and saponin （SAP）, a glycoside were tested. The soil washing experiments were performed in batch conditions at constant biosurfactant concentration （3%）. Both biosurfactants differed in natural pH, surface tension, critical micelle concentration and content of functional groups. After a single washing, TA （pH 3.44） more efficiently mobilized As than SAP （pH 5.44）. When both biosurfactants were used at the same pH （SAP adjusted to 3.44）, arsenic mobilization was improved by triple washing. The process efficiency for TA and SAP was similar, and depending on the soil sample, ranged between 50%-64%. Arsenic mobilization by TA and SAP resulted mainly from decomposition of Fe arsenates, followed by Fe3＋ complexation with biosurfactants. Arsenic was efficiently released from reducible and partially from residual fractions. In all soils, As（V） was almost completely removed, whereas content of As（III） was decreased by 37%-73%. SAP and TA might be used potentially to remove As from contaminated soils.展开更多
p-Arsanilic acid（p-ASA） is widely used in China as livestock and poultry feed additive for promoting animal growth.The use of organoarsenics poses a potential threat to the environment because it is mostly excreted ...p-Arsanilic acid（p-ASA） is widely used in China as livestock and poultry feed additive for promoting animal growth.The use of organoarsenics poses a potential threat to the environment because it is mostly excreted by animals in its original form and can be transformed by UV–Vis light excitation.This work examined the initial rate and efficiency of p-ASA phototransformation under UV-C disinfection lamp.Several factors influencing p-ASA phototransformation,namely,p H,initial concentration,temperature,as well as the presence of Na Cl,NH4＋,and humic acid,were investigated.Quenching experiments and LC–MS were performed to investigate the mechanism of p-ASA phototransformation.Results show that p-ASA was decomposed to inorganic arsenic（including As（Ⅲ） and As（V））and aromatic products by UV-C light through direct photolysis and indirect oxidation.The oxidation efficency of p-ASA by direct photosis was about 32%,and those by HOU and1O2 were 19% and 49%,respectively.Cleavage of the arsenic–benzene bond through direct photolysis,HOU oxidation or1O2 oxidation results in simultaneous formation of inorganic As（Ⅲ）,As（IV）,and As（V）.Inorganic As（Ⅲ） is oxidized to As（IV） and then to As（V） by1O2 or HOU.As（IV） can undergo dismutation or simply react with oxygen to produce As（V） as well.Reactions of the organic moieties of p-ASA produce aniline,aminophenol and azobenzene derivatives as main products.The photoconvertible property of p-ASA implies that UV disinfection of wastewaters from poultry and swine farms containing p-ASA poses a potential threat to the ecosystem,especially agricultural environments.展开更多
<strong>Objective:</strong> Metals including arsenic, lead, mercury, and cadmium are toxic and can increase cardiovascular disease risk. High-sensitivity C-reactive protein (hs-CRP) is a biomarker for infl...<strong>Objective:</strong> Metals including arsenic, lead, mercury, and cadmium are toxic and can increase cardiovascular disease risk. High-sensitivity C-reactive protein (hs-CRP) is a biomarker for inflammation and cardiovascular risk. This study will evaluate the association between urinary speciated arsenic, cadmium, lead, and mercury and blood values of hs-CRP in the United States adult population. <strong>Methods:</strong> A cross-sectional study using the 2015-2016 NHANES dataset, conducting multivariate linear regressions to analyze selected urinary metals and links with serum hs-CRP. <strong>Results: </strong>The sample consisted of 780 adults. In adjusted models, arsenocholine was found to be protective of inflammation, whereas aresnous acid, which is an inorganic, toxic type of arsenic acid, was positively associated with hs-CRP (<em>b</em> = 2.53). <strong>Conclusion: </strong>Urinary arsenous acid is a significant predictor of hs-CRP which is a biomarker for CVD.展开更多
Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic（As） and cadmium（Cd） in Brazilian upland rice growing in soils polluted with both A...Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic（As） and cadmium（Cd） in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3–16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from 0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid（from 11.3% to 61.7%） made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal（loid）s in the grain of rice grown in soils polluted with both As and Cd.展开更多
Insights from the adverse effect of humic acid （HA） on arsenate removal with hydrous ferric oxide （HFO） coprecipitation can further our understanding of the fate of As（V） in water treatment process. The motivati...Insights from the adverse effect of humic acid （HA） on arsenate removal with hydrous ferric oxide （HFO） coprecipitation can further our understanding of the fate of As（V） in water treatment process. The motivation of our study is to explore the competitive adsorption mechanisms of humic acid and As（V） on HFO on the molecular scale. Multiple complementary techniques were used including macroscopic adsorption experiments, surface enhanced Raman scattering （SERS）, extended X-ray absorption fine structure （EXAFS） spectroscopy, flow-cell attenuated total reflectance Fourier transform infrared （ATR-FTIR） measurement, and charge distribution multisite complexation （CD- MUSIC） modeling. The As（V） removal efficiency was reduced from over 95% to about 10% with the increasing HA concentration to 25 times of As（V） mass concentration. The SERS analysis excluded the HA-As（V） complex formation. The EXAFS results indicate that As（V） formed bidentate binuclear surface complexes in the presence of HA as evidenced by an As-Fe distance of 3.26--3.31 ,~. The in situ ATR-FTIR measurements show that As（V） replaces surface hydroxyl groups and forms inner- sphere complex. High concentrations of HA may physically block the surface sites and inhibit the As（V） access. The adsorption of As（V） and HA decreased the point of zero charge of HFO from 7.8 to 5.8 and 6.3, respectively. The CD-MUSIC model described the zeta potential curves and adsorption edges of As（V） and HA reasonably well.展开更多
ZHANG Ting-dong, a medical professor from the First Affiliated Hospital of Harbin Medical University, was honored with the Outstanding Achievement in Life Science Award for the first application of arsenous acid in th...ZHANG Ting-dong, a medical professor from the First Affiliated Hospital of Harbin Medical University, was honored with the Outstanding Achievement in Life Science Award for the first application of arsenous acid in the treatment of leukemiaon September 9,展开更多
文摘Antibiotics have been used in animal feeding for long history.In recent years,much attention has been received for their negative effects on animal and human being as well.Technology has been focused on alternatives of antibotics,such as probiotics,oligosaccharides,acidifiers,Chinese herds,chemical drugs,and other environmental measures.Their mechanism,effects,related factors and their prospect in the future were discussed in this paper.
基金supported by the Faculty of Environmental Sciences,University of Warmia and Mazury in Olsztyn,Poland(No.GW/2013/24)
文摘Plant biosurfactants were used for the first time to remove As and co-existing metals from brownfield soils. Tannic acid （TA）, a polyphenol, and saponin （SAP）, a glycoside were tested. The soil washing experiments were performed in batch conditions at constant biosurfactant concentration （3%）. Both biosurfactants differed in natural pH, surface tension, critical micelle concentration and content of functional groups. After a single washing, TA （pH 3.44） more efficiently mobilized As than SAP （pH 5.44）. When both biosurfactants were used at the same pH （SAP adjusted to 3.44）, arsenic mobilization was improved by triple washing. The process efficiency for TA and SAP was similar, and depending on the soil sample, ranged between 50%-64%. Arsenic mobilization by TA and SAP resulted mainly from decomposition of Fe arsenates, followed by Fe3＋ complexation with biosurfactants. Arsenic was efficiently released from reducible and partially from residual fractions. In all soils, As（V） was almost completely removed, whereas content of As（III） was decreased by 37%-73%. SAP and TA might be used potentially to remove As from contaminated soils.
基金supported by the National Natural Science Foundation of China(Nos 51508423 and 21477090)
文摘p-Arsanilic acid（p-ASA） is widely used in China as livestock and poultry feed additive for promoting animal growth.The use of organoarsenics poses a potential threat to the environment because it is mostly excreted by animals in its original form and can be transformed by UV–Vis light excitation.This work examined the initial rate and efficiency of p-ASA phototransformation under UV-C disinfection lamp.Several factors influencing p-ASA phototransformation,namely,p H,initial concentration,temperature,as well as the presence of Na Cl,NH4＋,and humic acid,were investigated.Quenching experiments and LC–MS were performed to investigate the mechanism of p-ASA phototransformation.Results show that p-ASA was decomposed to inorganic arsenic（including As（Ⅲ） and As（V））and aromatic products by UV-C light through direct photolysis and indirect oxidation.The oxidation efficency of p-ASA by direct photosis was about 32%,and those by HOU and1O2 were 19% and 49%,respectively.Cleavage of the arsenic–benzene bond through direct photolysis,HOU oxidation or1O2 oxidation results in simultaneous formation of inorganic As（Ⅲ）,As（IV）,and As（V）.Inorganic As（Ⅲ） is oxidized to As（IV） and then to As（V） by1O2 or HOU.As（IV） can undergo dismutation or simply react with oxygen to produce As（V） as well.Reactions of the organic moieties of p-ASA produce aniline,aminophenol and azobenzene derivatives as main products.The photoconvertible property of p-ASA implies that UV disinfection of wastewaters from poultry and swine farms containing p-ASA poses a potential threat to the ecosystem,especially agricultural environments.
文摘<strong>Objective:</strong> Metals including arsenic, lead, mercury, and cadmium are toxic and can increase cardiovascular disease risk. High-sensitivity C-reactive protein (hs-CRP) is a biomarker for inflammation and cardiovascular risk. This study will evaluate the association between urinary speciated arsenic, cadmium, lead, and mercury and blood values of hs-CRP in the United States adult population. <strong>Methods:</strong> A cross-sectional study using the 2015-2016 NHANES dataset, conducting multivariate linear regressions to analyze selected urinary metals and links with serum hs-CRP. <strong>Results: </strong>The sample consisted of 780 adults. In adjusted models, arsenocholine was found to be protective of inflammation, whereas aresnous acid, which is an inorganic, toxic type of arsenic acid, was positively associated with hs-CRP (<em>b</em> = 2.53). <strong>Conclusion: </strong>Urinary arsenous acid is a significant predictor of hs-CRP which is a biomarker for CVD.
基金supported by the National Natural Science Foundation of China (Nos. 41201300 and 41325003)the High Technology Research Development Program of the People's Republic of China (No. 2012AA06A204)
文摘Pot and field experiments were conducted to investigate the effects of water regimes on the speciation and accumulation of arsenic（As） and cadmium（Cd） in Brazilian upland rice growing in soils polluted with both As and Cd. In the pot experiment constant and intermittent flooding treatments gave 3–16 times higher As concentrations in soil solution than did aerobic conditions but Cd showed the opposite trend. Compared to arsenate, there were more marked changes in the arsenite concentrations in the soil solution as water management shifted, and therefore arsenite concentrations dominated the As speciation and bioavailability in the soil. In the field experiment As concentrations in the rice grains increased from 0.14 to 0.21 mg/kg while Cd concentrations decreased from 0.21 to 0.02 mg/kg with increasing irrigation ranging from aerobic to constantly flooding conditions. Among the various water regimes the conventional irrigation treatment produced the highest rice grain yield of 6.29 tons/ha. The As speciation analysis reveals that the accumulation of dimethylarsinic acid（from 11.3% to 61.7%） made a greater contribution to the increase in total As in brown rice in the intermittent and constant flooding treatments compared to the intermittent-aerobic treatment. Thus, water management exerted opposite effects on Cd and As speciation and bioavailability in the soil and consequently on their accumulation in the upland rice. Special care is required when irrigation regime methods are employed to mitigate the accumulation of metal（loid）s in the grain of rice grown in soils polluted with both As and Cd.
基金supported by the National Natural Science Foundation of China (No. 41373123, 41023005, 21321004)Research Center for EcoEnvironmental Sciences, Chinese Academy of Sciences (No. YSW2013A01)
文摘Insights from the adverse effect of humic acid （HA） on arsenate removal with hydrous ferric oxide （HFO） coprecipitation can further our understanding of the fate of As（V） in water treatment process. The motivation of our study is to explore the competitive adsorption mechanisms of humic acid and As（V） on HFO on the molecular scale. Multiple complementary techniques were used including macroscopic adsorption experiments, surface enhanced Raman scattering （SERS）, extended X-ray absorption fine structure （EXAFS） spectroscopy, flow-cell attenuated total reflectance Fourier transform infrared （ATR-FTIR） measurement, and charge distribution multisite complexation （CD- MUSIC） modeling. The As（V） removal efficiency was reduced from over 95% to about 10% with the increasing HA concentration to 25 times of As（V） mass concentration. The SERS analysis excluded the HA-As（V） complex formation. The EXAFS results indicate that As（V） formed bidentate binuclear surface complexes in the presence of HA as evidenced by an As-Fe distance of 3.26--3.31 ,~. The in situ ATR-FTIR measurements show that As（V） replaces surface hydroxyl groups and forms inner- sphere complex. High concentrations of HA may physically block the surface sites and inhibit the As（V） access. The adsorption of As（V） and HA decreased the point of zero charge of HFO from 7.8 to 5.8 and 6.3, respectively. The CD-MUSIC model described the zeta potential curves and adsorption edges of As（V） and HA reasonably well.
文摘ZHANG Ting-dong, a medical professor from the First Affiliated Hospital of Harbin Medical University, was honored with the Outstanding Achievement in Life Science Award for the first application of arsenous acid in the treatment of leukemiaon September 9,
