[Objective] This study aimed to understand the status of heavy metal contamination in edible fungi, thereby providing some scientific basis for the safety of edible fungi. [Method] The heavy metal contamination status...[Objective] This study aimed to understand the status of heavy metal contamination in edible fungi, thereby providing some scientific basis for the safety of edible fungi. [Method] The heavy metal contamination status in four kinds of edible fungi, i.e., shitake mushroom, mushroom, agaric and needle mushroom, from Guiyang City and Tongren City, Guizhou Province was evaluated by flame atomic absorption spectrophotometry. [Result] Cu, Mn, Cr and Ni were detected in the four kinds of edible fungi from Guiyang and Tongren; the Cr contents in the four kinds of edible fungi from Guiyang and Tongren all exceeded the national standard, and the Cu contents all met the national standard; The Ni contents in agaric and needle mushroom from Guiyang, and the Ni contents in the four kinds of edible fungi from Tongren, all exceeded the national standard; the enrichment capacity of the four kinds of edible fungi for the four kinds of heavy metal elements ranked as Cu＇s Mn＇s Cr＇s Ni＇s; among the four kinds of edible fungi, mushroom showed the strongest enrichment capacity for the four kinds of heavy metal elements. [Conclusion] The heavy metal contamination in the four kinds of edible fungi was all severe in Guiyang and Tongren, especially in Tongren. There has been currently no national standard for Mn content in edible fungi, which needs to be developed as soon as possible.展开更多
The bioavailability of five divalent cationic heavy metals （Pb, Cd, Cu, Zn and Ni） in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals （SEMs...The bioavailability of five divalent cationic heavy metals （Pb, Cd, Cu, Zn and Ni） in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals （SEMs） to acid volatile sulfide （AVS）. Atomic absorption spectrometry （AAS） and X-ray powder diffraction （XRD） were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g （dry weight）. The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake.展开更多
The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. （Plantagra）, plant materials after pyrolisis （cha...The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. （Plantagra）, plant materials after pyrolisis （charcoal） and composts are compared. Humus systems are characterized by Kononova-Belchikova＇s method, and heavy metals content was measured by atomic absorption spectroscopy （AAS）. Humic acids from the International Humic Substances Society （IHSS） collection are the standards for humus substances quality of compared products. Data obtained for leonardite indicate that the studied substances from factory, Izmir, Turkey contain humic acids over 94%. Compared to the standard, heavy metals content in these materials demonstrate high amounts. Organic carbon content in the composts is very low compared to the leonardite materials and IHSS collection, where the heavy metals content is lower. Biotransformed lignite is characterized with lower content of organic carbon, but humic acids are with high degree of humification. Results obtained show that the fourth studied humus systems may be used in agriculture on base of the high humic acids content. It is recommended to measure heavy metals content before applying the materials in agriculture.展开更多
Photocatalytic reduction of Cr（VI） by TiO2 suspension has been studied with the purpose of removing the toxic and carcinogenic Cr（VI） ions from water. The photocatalytic reduction was carried out in batch reactor,...Photocatalytic reduction of Cr（VI） by TiO2 suspension has been studied with the purpose of removing the toxic and carcinogenic Cr（VI） ions from water. The photocatalytic reduction was carried out in batch reactor, in which the influences of the presence ofmalonic and oxalic acids as well as of iron and lead ions on the degree of the reduction have been systematically evaluated. The results of the research indicated that the presence of malonic and oxalic acids with increasing concentration can improve the photoreduction. The increase in the Cr（V1） photoreduction is due to OH radical capturing by the organic acids so that it prevents the recombination of the OH radical and the free electron, and therefore can provide enough electron supply for Cr（VI） photoreduction. The effectiveness of Cr（VI） photoreduction is also enhanced by the addition of increasing concentration of both Fe（Ⅲ） and Pb（Ⅱ） ions through synergic effect. It is also found that the degree of the photopreduction is strongly influenced by solution acidity and the most effective Cr（VI） photoreduction is obtained at lower pH than 5, either in the absence or presence of the organic acids and the heavy metal ions.展开更多
During the 17th Century, Parral City in the Chihuahua State in Mexico was one of the most important miner zones in the whole world. After more than three centuries important amounts of residuals, known as tailings, wi...During the 17th Century, Parral City in the Chihuahua State in Mexico was one of the most important miner zones in the whole world. After more than three centuries important amounts of residuals, known as tailings, with high contents of heavy metals were generated. These residuals are a potential risk for the environment and human health. Given to that, it decided to carry out the analysis of the concentrations of cadmium, lead, chromium, zinc and arsenics, in topsoil samples susceptible of airborne transport and accumulation in risky zones （populated areas）. A 120 kin： area was selected, this include Parral City and its surroundings. From this area 30 samples were obtained. For this purpose, Atomic Absorption Spectroscopy technique was used, expecting high concentrations of heavy metals, above the permit limits, since several studies carried out in the same region, as in San Francisco del Oro Chihuahua, show that the concentrations of all the elements sampled, in topsoil, were above the limits. The analysis in the space distribution of the heavy metal detected will allow us to set the points with the highest susceptibility to the accumulation of those pollutants and to propose mitigation measures and control.展开更多
A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2...A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2009. Samples were collected once a week based on the pig production cycle, namely gestation, farrowing, weaning and fattening. Analysis of nutrients and heavy metals were determined by means of Inductively Coupled Plasma Atomic Emission Spectroscopy （ICP）. Total Nitrogen （TN） was determined by the Kjeldahl method. The main results showed that pig manures were characterized by high nutrients and heavy metals contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manure management system. Further, piggery wastewaters were characterized by very low concentrations of nutrients and heavy metals as result of their dilution with flushing water mainly used for cleaning the pigsties. Manure and wastewaters samples from weaning pigs contained the highest concentrations of nutrients and heavy metals that could be due to high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manures in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manures but the use of flushing water should be reduced as it can lead to further environmental pollution.展开更多
In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen, sediment samples were collected, treated and analyzed for cadmium, chromium, cobalt, copper, mangan...In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen, sediment samples were collected, treated and analyzed for cadmium, chromium, cobalt, copper, manganese, nickel, lead, iron, zinc and vanadium by the atomic absorption spectrometric analysis. The result is that cadmium, cobalt and lead concentrations were high and other elements are low or the same as natural background. It is concluded that the high cadmium, cobalt and lead levels in coral reefs sediments will have negative effects on marine life of the sites, so further researches are needed to characterize the sources fate, biogeochemical processes and impacts of these trace elements on coral reefs and marine of the region.展开更多
The increasing global concern over the public health impacts attributed to environmental pollution led us to investigate and compare the deposition of some heavy metals in mosses from an urban area, Aramoko Ekiti and ...The increasing global concern over the public health impacts attributed to environmental pollution led us to investigate and compare the deposition of some heavy metals in mosses from an urban area, Aramoko Ekiti and a rural area, Are Ekiti. Both towns are located in the SouthWest, Nigeria. Moss samples were collected at different sites in the two towns. These samples were then digested in acid and analysed for Cd, Cr, Ni, Pb and Cu, using a flame atomic absorption spectrometer. The results of the study show variations in the concentrations of the heavy metals among the different sites in each town as well as between the two towns. Apart from cd which was suspected to have originated from natural sources in the investigated samples, the relatively higher concentrations of the other metals in Aramoko-Ekiti suggests an important anthropogenic source which we suspect to be automobiles since there are little or no industrial or mining activities within the town. Furthermore, the relatively higher concentrations of the metals exhibited by moss samples collected around locations prone to higher traffic situations in the two towns such as roadsides, filling stations and garages stresses the significance of traffic density in heavy metal pollution of the environment. These places （filling stations and garages） should be sited far away from residential areas. Also, residences should be sited at considerably far distances from major roads. These will prevent the bioaccumulation of the heavy metals in residents. Though, the results show that Aramoko-Ekiti is more polluted with the heavy metals than Are-Ekiti, the concentration of the heavy metals were still within the permissible limits. Given the results of this work and similar ones, there is need to evaluate the pollution status of the environment from time to time especially the urban areas and high traffic areas.展开更多
In this paper, we describe the synthesis of a novel copper ion hapten using the copper mercaptide of penicillenic acid （CMPA） derived from penicillin. Results from tests with immune rabbits indicate that： （i） A n...In this paper, we describe the synthesis of a novel copper ion hapten using the copper mercaptide of penicillenic acid （CMPA） derived from penicillin. Results from tests with immune rabbits indicate that： （i） A new antigen synthesized with CMPA has good stability and is safe for immunizing animals with no toxic phenomena being found in animal experiments; （ii） the immunogenic antigen （CMPA-BSA） can stimulate the immune system to produce specific antibodies with high titrations, up to 150000; and （iii） antibodies in antisera showed higher affinity to OVA-GSH-CuC1 than OVA-GSH, which indicates that the antibodies have specific affinity towards copper ions. These results confirm that the novel hapten and relevant antigen for copper ion have been successfully synthesized, giving progress towards an immunoassay for copper ions in environmental and food samples.展开更多
基金Supported by Project of Guizhou Provincial Department of Science and Technology[QKHJ(2011)2164]~~
文摘[Objective] This study aimed to understand the status of heavy metal contamination in edible fungi, thereby providing some scientific basis for the safety of edible fungi. [Method] The heavy metal contamination status in four kinds of edible fungi, i.e., shitake mushroom, mushroom, agaric and needle mushroom, from Guiyang City and Tongren City, Guizhou Province was evaluated by flame atomic absorption spectrophotometry. [Result] Cu, Mn, Cr and Ni were detected in the four kinds of edible fungi from Guiyang and Tongren; the Cr contents in the four kinds of edible fungi from Guiyang and Tongren all exceeded the national standard, and the Cu contents all met the national standard; The Ni contents in agaric and needle mushroom from Guiyang, and the Ni contents in the four kinds of edible fungi from Tongren, all exceeded the national standard; the enrichment capacity of the four kinds of edible fungi for the four kinds of heavy metal elements ranked as Cu＇s Mn＇s Cr＇s Ni＇s; among the four kinds of edible fungi, mushroom showed the strongest enrichment capacity for the four kinds of heavy metal elements. [Conclusion] The heavy metal contamination in the four kinds of edible fungi was all severe in Guiyang and Tongren, especially in Tongren. There has been currently no national standard for Mn content in edible fungi, which needs to be developed as soon as possible.
基金Supported by the National Natural Science Foundation of China(No.20967003)the Project of the Government of Guiyang City(No.[2010]5-2)
文摘The bioavailability of five divalent cationic heavy metals （Pb, Cd, Cu, Zn and Ni） in 10 superficial sediment samples from Baihua Lake was assessed based on the molar ratio of simultaneously extracted metals （SEMs） to acid volatile sulfide （AVS）. Atomic absorption spectrometry （AAS） and X-ray powder diffraction （XRD） were used to determine the heavy metal concentrations and examine the mineralogy of the crystalline phases, respectively. The AVS loadings in sediments from Baihua Lake ranged from 64.30 to 350.08 ~rnol/g （dry weight）. The corresponding SEM levels for the sampling sites varied from 1.770 to 14.660 vrnol/g. The molar ratio of SEMs to AVS ranged from 0.014 to 0.084 with a mean value of 0.034. The XRD analysis also confirmed the presence of some metal sulfides in sediments from Baihua Lake. The SEMs/AVS ratios for all sampling sites were significantly lower than 1.0, indicating that AVS in the sediments was sufficient to bind the five heavy metals; thus, these heavy metals are currently not significantly bioavailable to benthic organisms. Comparing the SEMs results to published guideline values for metal toxicity to benthic organisms in sediments, however, suggests that Zn and Ni pose a risk at some sampling locations in Baihua Lake.
文摘The aim of the study was to characterize humus system of natural and artificial products. Humus systems from leonardite, lignite biotransformed with Trichoderma sp. （Plantagra）, plant materials after pyrolisis （charcoal） and composts are compared. Humus systems are characterized by Kononova-Belchikova＇s method, and heavy metals content was measured by atomic absorption spectroscopy （AAS）. Humic acids from the International Humic Substances Society （IHSS） collection are the standards for humus substances quality of compared products. Data obtained for leonardite indicate that the studied substances from factory, Izmir, Turkey contain humic acids over 94%. Compared to the standard, heavy metals content in these materials demonstrate high amounts. Organic carbon content in the composts is very low compared to the leonardite materials and IHSS collection, where the heavy metals content is lower. Biotransformed lignite is characterized with lower content of organic carbon, but humic acids are with high degree of humification. Results obtained show that the fourth studied humus systems may be used in agriculture on base of the high humic acids content. It is recommended to measure heavy metals content before applying the materials in agriculture.
文摘Photocatalytic reduction of Cr（VI） by TiO2 suspension has been studied with the purpose of removing the toxic and carcinogenic Cr（VI） ions from water. The photocatalytic reduction was carried out in batch reactor, in which the influences of the presence ofmalonic and oxalic acids as well as of iron and lead ions on the degree of the reduction have been systematically evaluated. The results of the research indicated that the presence of malonic and oxalic acids with increasing concentration can improve the photoreduction. The increase in the Cr（V1） photoreduction is due to OH radical capturing by the organic acids so that it prevents the recombination of the OH radical and the free electron, and therefore can provide enough electron supply for Cr（VI） photoreduction. The effectiveness of Cr（VI） photoreduction is also enhanced by the addition of increasing concentration of both Fe（Ⅲ） and Pb（Ⅱ） ions through synergic effect. It is also found that the degree of the photopreduction is strongly influenced by solution acidity and the most effective Cr（VI） photoreduction is obtained at lower pH than 5, either in the absence or presence of the organic acids and the heavy metal ions.
文摘During the 17th Century, Parral City in the Chihuahua State in Mexico was one of the most important miner zones in the whole world. After more than three centuries important amounts of residuals, known as tailings, with high contents of heavy metals were generated. These residuals are a potential risk for the environment and human health. Given to that, it decided to carry out the analysis of the concentrations of cadmium, lead, chromium, zinc and arsenics, in topsoil samples susceptible of airborne transport and accumulation in risky zones （populated areas）. A 120 kin： area was selected, this include Parral City and its surroundings. From this area 30 samples were obtained. For this purpose, Atomic Absorption Spectroscopy technique was used, expecting high concentrations of heavy metals, above the permit limits, since several studies carried out in the same region, as in San Francisco del Oro Chihuahua, show that the concentrations of all the elements sampled, in topsoil, were above the limits. The analysis in the space distribution of the heavy metal detected will allow us to set the points with the highest susceptibility to the accumulation of those pollutants and to propose mitigation measures and control.
文摘A large scale pig farm located in the North West of Beijing that applies the gan qing fen manure management system was selected and a continuous sampling of manures and wastewaters was performed from June to October 2009. Samples were collected once a week based on the pig production cycle, namely gestation, farrowing, weaning and fattening. Analysis of nutrients and heavy metals were determined by means of Inductively Coupled Plasma Atomic Emission Spectroscopy （ICP）. Total Nitrogen （TN） was determined by the Kjeldahl method. The main results showed that pig manures were characterized by high nutrients and heavy metals contents that might be due to the solid fraction separation from the liquid fraction under the gan qing fen manure management system. Further, piggery wastewaters were characterized by very low concentrations of nutrients and heavy metals as result of their dilution with flushing water mainly used for cleaning the pigsties. Manure and wastewaters samples from weaning pigs contained the highest concentrations of nutrients and heavy metals that could be due to high supplementation rates of these minerals in the weaner diets. In general, it seems that the manual daily collection of pig manures in the gan qing fen system is an efficient practice in order to maintain nutrient contents in pig manures but the use of flushing water should be reduced as it can lead to further environmental pollution.
文摘In order to determine and assess the concentrations of trace elements in coral reefs sediments from Red Sea of Yemen, sediment samples were collected, treated and analyzed for cadmium, chromium, cobalt, copper, manganese, nickel, lead, iron, zinc and vanadium by the atomic absorption spectrometric analysis. The result is that cadmium, cobalt and lead concentrations were high and other elements are low or the same as natural background. It is concluded that the high cadmium, cobalt and lead levels in coral reefs sediments will have negative effects on marine life of the sites, so further researches are needed to characterize the sources fate, biogeochemical processes and impacts of these trace elements on coral reefs and marine of the region.
文摘The increasing global concern over the public health impacts attributed to environmental pollution led us to investigate and compare the deposition of some heavy metals in mosses from an urban area, Aramoko Ekiti and a rural area, Are Ekiti. Both towns are located in the SouthWest, Nigeria. Moss samples were collected at different sites in the two towns. These samples were then digested in acid and analysed for Cd, Cr, Ni, Pb and Cu, using a flame atomic absorption spectrometer. The results of the study show variations in the concentrations of the heavy metals among the different sites in each town as well as between the two towns. Apart from cd which was suspected to have originated from natural sources in the investigated samples, the relatively higher concentrations of the other metals in Aramoko-Ekiti suggests an important anthropogenic source which we suspect to be automobiles since there are little or no industrial or mining activities within the town. Furthermore, the relatively higher concentrations of the metals exhibited by moss samples collected around locations prone to higher traffic situations in the two towns such as roadsides, filling stations and garages stresses the significance of traffic density in heavy metal pollution of the environment. These places （filling stations and garages） should be sited far away from residential areas. Also, residences should be sited at considerably far distances from major roads. These will prevent the bioaccumulation of the heavy metals in residents. Though, the results show that Aramoko-Ekiti is more polluted with the heavy metals than Are-Ekiti, the concentration of the heavy metals were still within the permissible limits. Given the results of this work and similar ones, there is need to evaluate the pollution status of the environment from time to time especially the urban areas and high traffic areas.
基金supported by the National Natural Science Foundation of China (Grant No. 30821005)National High Technology Research and Development Program of China (Grant No. 2007AA10Z401)
文摘In this paper, we describe the synthesis of a novel copper ion hapten using the copper mercaptide of penicillenic acid （CMPA） derived from penicillin. Results from tests with immune rabbits indicate that： （i） A new antigen synthesized with CMPA has good stability and is safe for immunizing animals with no toxic phenomena being found in animal experiments; （ii） the immunogenic antigen （CMPA-BSA） can stimulate the immune system to produce specific antibodies with high titrations, up to 150000; and （iii） antibodies in antisera showed higher affinity to OVA-GSH-CuC1 than OVA-GSH, which indicates that the antibodies have specific affinity towards copper ions. These results confirm that the novel hapten and relevant antigen for copper ion have been successfully synthesized, giving progress towards an immunoassay for copper ions in environmental and food samples.
