The cancer risk and the non-cancer hazard index for inhabitants exposed to As, Cd, Cu and Zn in t... more The cancer risk and the non-cancer hazard index for inhabitants exposed to As, Cd, Cu and Zn in the soils and stream waters of the abandoned Songcheon Au-Ag mine area were evaluated. Mean concentrations of As, Cd, Cu, Pb and Zn in agricultural soils were 230, 2.5, 120, 160, and 164 mg kg )1 , respectively. Mean concentrations of As, Cd and Zn of the water in the stream where drinking water was drawn was 246 lg L )1 , 161 lg L )1 and 3899 lg L )1 , respectively. These levels are significantly higher than the permissible levels for drinking water quality recommended by Korea and WHO. The resulting human health risks to farmers who inhabited the surrounding areas due to drinking water were summarized as follows: (1) the non-cancer health hazard indices showed that the toxic risk due to As and Cd in drinking water were 10 and 4 times, respectively, greater than those induced by the safe average daily dosages of the respective chemicals.
The Okchon black shale in Korea provides an important example of natural geological materials con... more The Okchon black shale in Korea provides an important example of natural geological materials containing toxic elements; the Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won and Chu-Bu areas are underlain by these black shales and slates of the Guryongsan Formation. This formation is part of the Okchon Group which is found in the central part of Korea. Geochemical surveys were undertaken in these five study areas in the Okchon Zone in order to examine the level of enrichment and dispersion patterns of potentially toxic elements in rocks and soils. After appropriate preparation, samples were analysed by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectrometry for a range of elements. Arsenic, Cu, Mo, V, U and Zn are highly enriched in the Okchon black shales and their mean concentrations are significantly higher than those in black slates. These elements are closely associated with one another from a geochemical viewpoint and may be enriched simultaneously. Mean concentrations of As, Mo and U in soils derived from black shales occurring in the Duk-Pyung and Chu-Bu areas are higher than the permissible level suggested by , and the enrichment index decreases in the order of Duk-Pyung b Chu-Bu b Chung-Joo b Geum-Kwan I-Won areas. Uranium-bearing minerals such as uraninite and brannerite have been identified in black shales from the Chung-Joo area by electron probe micro-analysis. Uraninite grains are closely associated with monazite and pyrite with a grain size ranging from 2"m to 10"m whereas brannerite grains occur as a euhedral form 50 "m in diameter.
The Okchon black shale in Korea provides a typical example of natural geological materials enrich... more The Okchon black shale in Korea provides a typical example of natural geological materials enriched with potentially toxic elements. The Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won, Bo-Eun and Chu-Bu areas are underlain by these black shales and slates of the Guryongsan Formation or the Changri Formation, which are parts of the Okchon Group in the central part of the southern Korean Peninsula. In order to investigate the enrichment levels and dispersion patterns of potentially toxic elements in the rock-soil-plant system, environmental geochemical surveys were undertaken in the above six study areas in the Okchon Zone. After appropriate preparation, rock and soil samples were analyzed for potentially toxic elements by instrumental neutron activation analysis (INAA) and inductively coupled plasma atomic emission spectrometry (ICP-AES), and plant samples by atomic absorption spectrometry (AAS). In particular, Ba, Cd, Mo, V and U in Okchon black shales are highly enriched, and their mean concentrations are significantly higher than those in black slates. These elements are geochemically associated, and might be enriched simultaneously. The highest mean concentrations of 42.0 µg g 1 As, 2100 µg g 1 Ba, 10.9 µg g 1 Cd, 213 µg g 1 Mo, 83 µg g 1 U, 938 µg g 1 V and 394 µg g 1 Zn are found in black shales from the Duk-Pyung area. Mean concentrations of As, Mo and U in soils overlying black shales occurring in the Duk-Pyung area (30 µg g 1 As, 24 µg g 1 Mo and 50 µg g 1 U) and Chu-Bu area (39 µg g 1 As, 15 µg g 1 Mo and 27 µg g 1 U) are higher than the permissible level. Enrichment index values of the six study areas decrease in the order of Duk-Pyung > Chu-Bu > Bo-Eun > Chung-Joo > Geum-Kwan D I-Won areas. Relationships between trace element concentrations in soils and plants are significantly correlated, and the biological absorption coefficients (BAC) in plants are in the order of Cd > Zn D Cu > Pb, which suggests that Cd is more bioavailable to plants than the other elements. Cadmium concentrations in plant species decrease in the order of chinese cabbage > red pepper > soybean D sesame > rice stalk > corn > rice grain. From the result of sequential extraction analysis of soils, relatively high proportions of Cu, Pb and Zn are present as residual fractions, and that of Cd as non-residual fractions. Cadmium occurs predominantly as exchangeable=water-acid soluble phase in soils, and this is in agreement with the findings of high Cd concentrations in plants.
6 b S Supporting Information 23 24 ' INTRODUCTION 25 Surface-enhanced Raman scattering (SERS) is ... more 6 b S Supporting Information 23 24 ' INTRODUCTION 25 Surface-enhanced Raman scattering (SERS) is a promising 26 technique for the simultaneous detection of multiplex target 27 molecules. In contrast to the broad and relatively featureless spectra 28 of fluorescence labels, SERS labels produce signals with very 29 narrow bandwidth and fingerprint-like information for analytes, 30 which give them a high multiplexing capacity. Other advantages 31 of SERS include lack of photobleaching and self-quenching, as well 32 as the use of a single excitation source for multiple species. 1À3 In 33 particular, SERS nano tags are playing an increasingly important 34 role in bioassays and biomedical diagnostics, including for detec-35 tion of DNA and RNA, 4À6 proteins, 3,7À9 viral pathogens, 10 and 36 cellular imaging. 11À16 Specific nanostructures that can provide a 37 high level of electromagnetic field enhancement are a prerequisite 38 in order to obtain stable spectroscopic signatures and sensitive 39 detection. 17 With the exception of the commonly used Ag and Au 40 nanoparticles, various nanostructures have been used to prepare 41 SERS tags, such as Au nanorods, 18 nanoshells, 19À21 hollow gold 42 nanosphere, 22À24 AuÀAg nanocages, 25 and Au nanostars. 26 43 Most of the SERS nano tags developed to date have taken 44 advantage of the high sensitivity offered by SERS and the specificity 45 offered by surface probing molecules. However, a common draw-46 back of these approaches is that the tags are not isolated from the 47 environment and thus are easily influenced by surrounding con-48 ditions. For instance, signals from cell components, in addition to 49 SERS signals generated by reporter molecules, have been ob-50 served from unprotected SERS tags used for pH sensing in living 51 cells. 27 Therefore, it is necessary to prepare SERS nanoparticle 52 tags with protective shells, which can prevent desorption of 53 Raman reporters and adsorption of external species. To this end, 54 several approaches have been developed to prepare polymer-or 55 silica-encapsulated nanoparticle SERS tags. Polymer-encapsu-56 lated nanoparticle SERS tags have been prepared by using thiol-57 modified polyethylene glycol as a stabilizer and protective 58 shell. 9,14 Likewise, metal nanoparticles developed from polystyr-59 ene-block-poly(acrylic acid) (PS 154 -b-PAA 60 ), an amphiphilic di-60 block copolymer, through self-assembly have also been reported. 28 61 However, due to its optical transparency, easy surface functio-62 nalization, and biocompatibility, silica has been considered a 63 good coating material for the synthesis of SERS nano tags. 64 Mulvaney and co-workers 29 were the first to prepare "glass-65 ABSTRACT: The use of silica shells offers many advantages in 8 surface-enhanced Raman scattering (SERS)-based biological 9 sensing applications due to their optical transparency, remark-10
To investigate the dispersion patterns and the characteristics of heavy metal contamination due t... more To investigate the dispersion patterns and the characteristics of heavy metal contamination due to urbanisation and industrialisation, soils and dusts collected from the Seoul area were analysed for Cu, Pb, Zn and Cd. The metal concentrations in most soils and dusts are higher than the world averages. The pollution index ((Σ Metal concentrations in soils/Permissible level for metal)÷(Number of metals)) of soils and dusts is > 1 in most of the Seoul area, a result that concurs with the industrialisation and urbanisation index of the Seoul area. The soils are contaminated with Cu, Zn, Cd and particularly Pb. This suggests that the contamination of the soils in the Seoul area are mainly caused by vehicular emissions. The pollution index of soil is the highest in the Kuro area where Cu and Zn contamination in soils are due to the indigenous brass and bronze factories. From the discriminant analysis, the Seoul area may be partitioned into control, traffic and industrialized areas by the metal concentrations in the order of Zn > Cu > Pb.
The cancer risk and the non-cancer hazard index for inhabitants exposed to As, Cd, Cu and Zn in t... more The cancer risk and the non-cancer hazard index for inhabitants exposed to As, Cd, Cu and Zn in the soils and stream waters of the abandoned Songcheon Au-Ag mine area were evaluated. Mean concentrations of As, Cd, Cu, Pb and Zn in agricultural soils were 230, 2.5, 120, 160, and 164 mg kg )1 , respectively. Mean concentrations of As, Cd and Zn of the water in the stream where drinking water was drawn was 246 lg L )1 , 161 lg L )1 and 3899 lg L )1 , respectively. These levels are significantly higher than the permissible levels for drinking water quality recommended by Korea and WHO. The resulting human health risks to farmers who inhabited the surrounding areas due to drinking water were summarized as follows: (1) the non-cancer health hazard indices showed that the toxic risk due to As and Cd in drinking water were 10 and 4 times, respectively, greater than those induced by the safe average daily dosages of the respective chemicals.
The Okchon black shale in Korea provides an important example of natural geological materials con... more The Okchon black shale in Korea provides an important example of natural geological materials containing toxic elements; the Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won and Chu-Bu areas are underlain by these black shales and slates of the Guryongsan Formation. This formation is part of the Okchon Group which is found in the central part of Korea. Geochemical surveys were undertaken in these five study areas in the Okchon Zone in order to examine the level of enrichment and dispersion patterns of potentially toxic elements in rocks and soils. After appropriate preparation, samples were analysed by instrumental neutron activation analysis and inductively coupled plasma atomic emission spectrometry for a range of elements. Arsenic, Cu, Mo, V, U and Zn are highly enriched in the Okchon black shales and their mean concentrations are significantly higher than those in black slates. These elements are closely associated with one another from a geochemical viewpoint and may be enriched simultaneously. Mean concentrations of As, Mo and U in soils derived from black shales occurring in the Duk-Pyung and Chu-Bu areas are higher than the permissible level suggested by , and the enrichment index decreases in the order of Duk-Pyung b Chu-Bu b Chung-Joo b Geum-Kwan I-Won areas. Uranium-bearing minerals such as uraninite and brannerite have been identified in black shales from the Chung-Joo area by electron probe micro-analysis. Uraninite grains are closely associated with monazite and pyrite with a grain size ranging from 2"m to 10"m whereas brannerite grains occur as a euhedral form 50 "m in diameter.
The Okchon black shale in Korea provides a typical example of natural geological materials enrich... more The Okchon black shale in Korea provides a typical example of natural geological materials enriched with potentially toxic elements. The Chung-Joo, Duk-Pyung, Geum-Kwan, I-Won, Bo-Eun and Chu-Bu areas are underlain by these black shales and slates of the Guryongsan Formation or the Changri Formation, which are parts of the Okchon Group in the central part of the southern Korean Peninsula. In order to investigate the enrichment levels and dispersion patterns of potentially toxic elements in the rock-soil-plant system, environmental geochemical surveys were undertaken in the above six study areas in the Okchon Zone. After appropriate preparation, rock and soil samples were analyzed for potentially toxic elements by instrumental neutron activation analysis (INAA) and inductively coupled plasma atomic emission spectrometry (ICP-AES), and plant samples by atomic absorption spectrometry (AAS). In particular, Ba, Cd, Mo, V and U in Okchon black shales are highly enriched, and their mean concentrations are significantly higher than those in black slates. These elements are geochemically associated, and might be enriched simultaneously. The highest mean concentrations of 42.0 µg g 1 As, 2100 µg g 1 Ba, 10.9 µg g 1 Cd, 213 µg g 1 Mo, 83 µg g 1 U, 938 µg g 1 V and 394 µg g 1 Zn are found in black shales from the Duk-Pyung area. Mean concentrations of As, Mo and U in soils overlying black shales occurring in the Duk-Pyung area (30 µg g 1 As, 24 µg g 1 Mo and 50 µg g 1 U) and Chu-Bu area (39 µg g 1 As, 15 µg g 1 Mo and 27 µg g 1 U) are higher than the permissible level. Enrichment index values of the six study areas decrease in the order of Duk-Pyung > Chu-Bu > Bo-Eun > Chung-Joo > Geum-Kwan D I-Won areas. Relationships between trace element concentrations in soils and plants are significantly correlated, and the biological absorption coefficients (BAC) in plants are in the order of Cd > Zn D Cu > Pb, which suggests that Cd is more bioavailable to plants than the other elements. Cadmium concentrations in plant species decrease in the order of chinese cabbage > red pepper > soybean D sesame > rice stalk > corn > rice grain. From the result of sequential extraction analysis of soils, relatively high proportions of Cu, Pb and Zn are present as residual fractions, and that of Cd as non-residual fractions. Cadmium occurs predominantly as exchangeable=water-acid soluble phase in soils, and this is in agreement with the findings of high Cd concentrations in plants.
6 b S Supporting Information 23 24 ' INTRODUCTION 25 Surface-enhanced Raman scattering (SERS) is ... more 6 b S Supporting Information 23 24 ' INTRODUCTION 25 Surface-enhanced Raman scattering (SERS) is a promising 26 technique for the simultaneous detection of multiplex target 27 molecules. In contrast to the broad and relatively featureless spectra 28 of fluorescence labels, SERS labels produce signals with very 29 narrow bandwidth and fingerprint-like information for analytes, 30 which give them a high multiplexing capacity. Other advantages 31 of SERS include lack of photobleaching and self-quenching, as well 32 as the use of a single excitation source for multiple species. 1À3 In 33 particular, SERS nano tags are playing an increasingly important 34 role in bioassays and biomedical diagnostics, including for detec-35 tion of DNA and RNA, 4À6 proteins, 3,7À9 viral pathogens, 10 and 36 cellular imaging. 11À16 Specific nanostructures that can provide a 37 high level of electromagnetic field enhancement are a prerequisite 38 in order to obtain stable spectroscopic signatures and sensitive 39 detection. 17 With the exception of the commonly used Ag and Au 40 nanoparticles, various nanostructures have been used to prepare 41 SERS tags, such as Au nanorods, 18 nanoshells, 19À21 hollow gold 42 nanosphere, 22À24 AuÀAg nanocages, 25 and Au nanostars. 26 43 Most of the SERS nano tags developed to date have taken 44 advantage of the high sensitivity offered by SERS and the specificity 45 offered by surface probing molecules. However, a common draw-46 back of these approaches is that the tags are not isolated from the 47 environment and thus are easily influenced by surrounding con-48 ditions. For instance, signals from cell components, in addition to 49 SERS signals generated by reporter molecules, have been ob-50 served from unprotected SERS tags used for pH sensing in living 51 cells. 27 Therefore, it is necessary to prepare SERS nanoparticle 52 tags with protective shells, which can prevent desorption of 53 Raman reporters and adsorption of external species. To this end, 54 several approaches have been developed to prepare polymer-or 55 silica-encapsulated nanoparticle SERS tags. Polymer-encapsu-56 lated nanoparticle SERS tags have been prepared by using thiol-57 modified polyethylene glycol as a stabilizer and protective 58 shell. 9,14 Likewise, metal nanoparticles developed from polystyr-59 ene-block-poly(acrylic acid) (PS 154 -b-PAA 60 ), an amphiphilic di-60 block copolymer, through self-assembly have also been reported. 28 61 However, due to its optical transparency, easy surface functio-62 nalization, and biocompatibility, silica has been considered a 63 good coating material for the synthesis of SERS nano tags. 64 Mulvaney and co-workers 29 were the first to prepare "glass-65 ABSTRACT: The use of silica shells offers many advantages in 8 surface-enhanced Raman scattering (SERS)-based biological 9 sensing applications due to their optical transparency, remark-10
To investigate the dispersion patterns and the characteristics of heavy metal contamination due t... more To investigate the dispersion patterns and the characteristics of heavy metal contamination due to urbanisation and industrialisation, soils and dusts collected from the Seoul area were analysed for Cu, Pb, Zn and Cd. The metal concentrations in most soils and dusts are higher than the world averages. The pollution index ((Σ Metal concentrations in soils/Permissible level for metal)÷(Number of metals)) of soils and dusts is > 1 in most of the Seoul area, a result that concurs with the industrialisation and urbanisation index of the Seoul area. The soils are contaminated with Cu, Zn, Cd and particularly Pb. This suggests that the contamination of the soils in the Seoul area are mainly caused by vehicular emissions. The pollution index of soil is the highest in the Kuro area where Cu and Zn contamination in soils are due to the indigenous brass and bronze factories. From the discriminant analysis, the Seoul area may be partitioned into control, traffic and industrialized areas by the metal concentrations in the order of Zn > Cu > Pb.
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