• Journal of Food Hygiene and Safety
• /
• v.34 no.4
• /
• pp.325-333
• /
• 2019

The present study was carried out to identify the distribution characteristics of heavy metals in ginseng and wood-cultivated ginseng reduction of dietary exposure. Samples of ginseng and wood-cultivated ginseng were collected from 14 and 5 regions across Korea, respectively. Lead (Pb), cadmium (Cd) and arsenic (Ar) were detected by ICP-MS after microwave digestion, whereas aluminum (Al) was determined using ICP. Cultivated ginseng peels were 16.2% of whole root, while the peels and fine roots amounted to 21.8% and 16.8% of whole wood-cultivated ginseng, respectively. Taking into account the weight and concentration of the heavy metals by root part, their distribution ratios were calculated and compared. The cultivated ginseng peels contained 40.3% Pb, 25.9% Cd, 47.6% As, and 89.9% Al. Meanwhile, heavy metals consisting of 27.2% Pb, 28.2% Cd, 48.3% As, and 56.8% Al were distributed in the peels of the wood-cultivated ginseng. There was no significant difference between the peels and fine roots of the wood-cultivated ginseng with respect to the distribution proportion of heavy metals, except for Al. These results indicate that the level of dietary exposure to heavy metals could be reduced by peeling ginseng and wood-cultivated ginseng prior to consumption.

• Journal of Food Hygiene and Safety
• /
• v.33 no.6
• /
• pp.453-459
• /
• 2018

This study was performed to investigate the contamination levels of heavy metals (such as lead, cadmium, arsenic and mercury) and aflatoxin (such as $B_1$, $B_2$, $G_1$ and $G_2$) in commercial herbs for food and medicine. The concentrations of the heavy metals were measured by the ICP-MS and a mercury analyzer. The aflatoxins were analyzed by a HPLC-florescence coupled with photochemical derivatization. The detection ranges of the lead, cadmium, arsenic and mercury were found to be 0.006~4.088 mg/kg, 0.002~2.150 mg/kg, ND~0.610 mg/kg and ND~0.0139 mg/kg respectively. Among the total samples, the 3 samples (2.6%) were not suitable for the specification of cadmium by the MFDS (Ministry of Food and Drug Safety). The 13 samples of the total 117 samples were aflatoxin positive (11.1%). The amount of aflatoxin $G_1$ was $0.7834{\mu}g/kg$ in the Puerariae Radix and aflatoxin $G_2$ were $0.3517{\mu}g/kg$, $0.4881{\mu}g/kg$ in two samples of the Glycyrrhizae Radix et Rhizoma, respectively. The aflatoxins $B_2$ and $G_1$ were simultaneously detected in the 10 Angelicae Gigantis Radix. The detection ranges of aflatoxins $B_2$ and $G_1$ were $0.2324{\sim}1.0358{\mu}g/kg$ and $0.7552{\sim}1.6545{\mu}g/kg$ respectively in Angelicae Gigantis Radix. The results of the current study suggest that continuous monitoring is needed for the proactive management of commercial herbs for food and medicine safety.

• Economic and Environmental Geology
• /
• v.50 no.3
• /
• pp.215-224
• /
• 2017

Arsenic (As) is known to be the most toxic element and frequently detected in groundwater environment. Inorganic As exists as arsenite [As(III)] and arsenate [As(V)] in reduced and oxidized environments, respectively. It has been reported that the toxicity of arsenite is much higher than that of arsenate and furthermore arsenite shows relatively higher mobility in aqueous environments. For this reason, there have been numerous researches on the process for oxidation of arsenite to arsenate to reduce the toxicity of arsenic. In particular, photooxidation has been considered to be simple, economical, and efficient to attain such goal. This study was conducted to evaluate the applicability of naturally-occurring goethite as a photocatalyst to substitute for $TiO_2$ which has been mostly used in the photooxidation processes so far. In addition, the effects of several factors on the overall performance of arsenite photocatalytic oxidation process were evaluated. The results show that the efficiency of the process was affected by total concentration of dissolved cations rather than by the kind of those cations and also the relatively higher pH conditions seemed to be more favorable to the process. In the case of coexistence of arsenite and arsenate, the removal tendency by adsorption onto goethite appeared to be different between arsenite and arsenate due to their different affinities with goethite, but any effect on the photocatalytic oxidation of arsenite was not observed. In terms of effect of humic acid on the process, it is likely that the higher concentration of humic acid reduced the overall performance of the arsenite photocatalytic oxidation as a result of competing interaction of activated oxygen species, such as hydroxyl and superoxide radicals, with arsenite and humic acid. In addition, it is revealed that the injection of oxygen gas improved the process because oxygen contributes to arsenite oxidation as an electron acceptor. Based on the results of the study, consequently, the photocatalytic oxidation of aqueous arsenite using goethite seems to be greatly feasible with the optimization of process.

• Journal of Korean Society of Environmental Engineers
• /
• v.39 no.1
• /
• pp.9-18
• /
• 2017

Arsenic (As) has been considered as the most toxic one among various hazardous materials and As contamination can be caused naturally and anthropogenically. Major forms of arsenic in groundwater are arsenite [(As(III)] and/or arsenate [(As(V)], depending on redox condition: arsenite and arsenate are predominant in reduced and oxidized environments, respectively. Because arsenite is much more toxic and mobile than arsenate, there have been a number of studies on the reduction of its toxicity through oxidation of As(III) to As(V). This study was initiated to develop photocatalytic oxidation process for treatment of groundwater contaminated with arsenite. The performance of two types of light sources (UV lamp and UV LED) was compared and the feasibility of goethite as a photocatalyst was evaluated. The highest removal efficiency of the process was achieved at a goethite dose of 0.05 g/L. Based on the comparison of oxidation efficiencies of arsenite between two light sources, the apparent performance of UV LED was inferior to that of UV lamp. However, when the results were appraised on the basis of their emitting UV irradiation, the higher performance was achieved by UV LED than by UV lamp. This study demonstrates that environmentally friendly process of goethite-catalytic photo-oxidation without any addition of foreign catalyst is feasible for the reduction of arsenite in groundwater containing naturally-occurring goethite. In addition, this study confirms that UV LED can be used in the photo-oxidation of arsenite as an alternative light source of UV lamp to remedy the drawbacks of UV lamp, such as long stabilization time, high electrical power consumption, short lifespan, and high heat output requiring large cooling facilities.

• Economic and Environmental Geology
• /
• v.36 no.3
• /
• pp.177-189
• /
• 2003

The main purposes of this study are to utilize mineralogical studies such as optical microscope, XRD and SEM/EDS analyses to characterize the oxidation of sulfide minerals and the mechanisms controlling the movement of dissolved metals from waste rocks at the abandoned Seobo mine. Mineralogical research of the waste rocks confirms the presence of anglesite, covellite, goethite, native sulfur and nsutite as secondary minerals, suggesting that these phases control the dissolved concentrations of As, Cu, Fe, Mn, Pb and Zn. The dissolved metals are precipitated, adsorbed and/or coprecipitated with(or within) Fe(Mn)-hydroxides and Mn(Fe)-hydroxides. The main phases of secondary mineral, Fe-hydroxide, can be classified as amorphous or poorly crystalline and more crystallized phases(e.g. goethite) by crystallinity. Amorphous or poorly crystalline Fe-hydroxide has relatively high As contents(9-24 wt.%). This poorly crystalline Fe-hydroxide changes toward more crystallized phase(e.g. goethite) which contains relatively low As(0.6-7.7 wt.%). These results are mainly due to the progressive release of As with the crystallization evolution of the As-trapping poorly crystalline Fe-hydroxides. It is also attributed to the differences of specific surface areas between the poorly crystalline Fe-hydroxides and well crystallized phases. The dissolved metals from waste rocks at Seobo mine area are naturally attenuated by a series of precipitation(as Fe, Mn, Cu, Pb), coprecipitation(Fe, Mn) and adsorption(As, Cu, Pb, An) reactions. The results of mineralogical researches permit to assess the environmental impacts of mine waste rocks in the areas, and can be used as a useful data to lay available mine restoration plan.

• Journal of Soil and Groundwater Environment
• /
• v.14 no.6
• /
• pp.78-86
• /
• 2009

Applicability of CaO and steel slag as stabilizers in the treatment of field and paddy soils near Pungjeong mine contaminated with arsenic and cationic heavy metals was investigated from batch and column experiments. Immobilization of heavy metals was evaluated by TCLP dissolution test. Immobility of heavy metal ions was less than 15% when steel slag alone was used. This result suggests that $Fe_2O_3$ and $SiO_2$, known as the major component of steel slag, have little effect for the immobilization of heavy metal ions due to acidity of TCLP solution. Immobilization of cationic heavy metals was little affected by the ratio of CaO and steel slag while arsenic removal was increased as the ratio of steel slag to CaO increased. In the column test, concentrations of both arsenic and cationic heavy metals in effluents were below the water discharge guideline over the entire reaction period. This result can be explained by the immobilization of cationic heavy metals from the increased pH in soil solution as well as by the formation of insoluble $Ca_3(AsO_4)_2$. From this work, it is possible to suggest that arsenic and cationic heavy metals can be concurrently stabilized by application of both CaO and steel slag.

• Radiation Oncology Journal
• /
• v.29 no.1
• /
• pp.28-35
• /
• 2011

Purpose: Recently, the use of radiosurgery as a local therapy in patients with early stage non-small cell lung cancer has become favored over surgical resection. To evaluate the efficacy of radiosurgery, we analyzed the results of stereotactic body radiosurgery in patients with primary or recurrent non-small cell lung cancer. Materials and Methods: We reviewed medical records retrospectively of total 24 patients (28 lesions) with non-small cell lung cancer (NSCLC) who received stereotactic body radiosurgery (SBRT) at Inha University Hospital. Among the 24 patients, 19 had primary NSCLC and five exhibited recurrent disease, with three at previously treated areas. Four patients with primary NSCLC received SBRT after conventional radiation therapy as a boost treatment. The initial stages were IA in 7, IB in 3, IIA in 2, IIB in 2, IIIA in 3, IIIB in 1, and IV in 6. The T stages at SBRT were T1 lesion in 13, T2 lesion in 12, and T3 lesion in 3. 6MV X-ray treatment was used for SBRT, and the prescribed dose was 15~60 Gy (median: 50 Gy) for PTV1 in 3~5 fractions. Median follow up time was 469 days. Results: The median GTV was 22.9 mL (range, 0.7 to 108.7 mL) and median PTV1 was 65.4 mL (range, 5.3 to 184.8 mL). The response rate at 3 months was complete response (CR) in 14 lesions, partial response (PR) in 11 lesions, and stable disease (SD) in 3 lesions, whereas the response rate at the time of the last follow up was CR in 13 lesions, PR in 9 lesions, SD in 2 lesions, and progressive disease (PD) in 4 lesions. Of the 10 patients in stage 1, one patient died due to pneumonia, and local failure was identified in one patient. Of the 10 patients in stages III-IV, three patients died, local and loco-regional failure was identified in one patient, and regional failure in 2 patients. Total local control rate was 85.8% (4/28). Local recurrence was recorded in three out of the eight lesions that received below biologically equivalent dose 100 $Gy_{10}$. Among 20 lesions that received above 100 $Gy_{10}$, only one lesion failed locally. There was a higher recurrence rate in patients with centrally located tumors and T2 or above staged tumors. Conclusion: SBRT using a CyberKnife was proven to be an effective treatment modality for early stage patients with NSCLC based on high local control rate without severe complications. SBRT above total 100 $Gy_{10}$ for peripheral T1 stage patients with NSCLC is recommended.

• Tuberculosis and Respiratory Diseases
• /
• v.53 no.3
• /
• pp.253-264
• /
• 2002

Background : It has been reported that the expression of protein which influences on the cell cycle is significantly involved in the development, progress, treatment response, and survival of cancer, and also that the degree of expression of p27 and CDK4 is related to the prognosis. Recent research has revealed that uteroglobin, tumor suppressor gene, is related to cell cycle. This study is focused on the relations between expression of proteins related to cell cycle and clinical index of and survival of NSCLC. Methods : We examined immunohistochemically specimens of 110 surgically resected NSCLCs for expression of p27, CDK, Uteroglobin. Tissue array slide were obtained from 110 surgically resected NSCLCs. Immunohistochemical staining was performed by immuno-peroxidase technique using avidin-biotinylated horseradish peroxidase complex. Results : In 110 patients with resected NSCLCs, the ratio of male to female was 87:13, the median age was $56.43{\pm}9.41$ yrs. The positive staining of p27 was detected in 75% of the cases. A non-statistically significant trend toward increased p27 expression was observed in smoker and squamous cell cancer. The positive staining of CDK4 was detected in 89%, which was the highest expression of protein among 3 types. The survival ratio of CDK4 negative staining group was higher than that of positive staining group, which was significant diffrernce(P<0.05). There was no association between p27 or uteroglobin expression and survival. Conclusion : The expression degree of CDK4 is related to the prognosis. This findings suggests that the measurement of CDK4 may be useful in identifying patient at high risk for disease recurrence and survival.

• Journal of Korean Society of Environmental Engineers
• /
• v.28 no.7
• /
• pp.731-737
• /
• 2006

Four well-characterized soils collected from A- and B-horizon in the Department of Energy Oak Ridge Reservation in USA, mainly distributed with Inceptisol(Inc) and Ultisol(Ult) soils, were used in this work. The bioaccessibility of arsenic as well as oxidation phenomena of As(III) was investigated with soils spiked with As(III) and As(V) using a physiologically based extraction test(PBET) at pH 1.5 and 1:100 soil to solution ratio. Also effect of aging time on the bioaccessibility of arsenic was investigated over the 6 months. After 48 hours(fresh) contacting As(V) solution with soils, all soils rapidly and strongly sequestrated As(V), especially Ult-B. However, little sequestration was observed after 3-months. When As(III) was spiked on the same soils, a great portion of As(III) was oxidized to As(V) after 48 hrs, especially Inc-A and Ult-A soils, which is strongly related with Mn content in soils. By using As(III)-spiked soils, much reduced bioaccessibility as total arsenic was observed from Inc-B and Ult-B soils over the 6 months aging time compared to that from Inc-A and Ult-A soils. This result can be explained by the continuous sequestration of As(V), produced from oxidation of As(III), onto Inc-B and Ult-B soils having much amount of iron. The trend of As(III) sequestration over six months aging time was quite similar with that of As(V) sequestration.

• Economic and Environmental Geology
• /
• v.42 no.5
• /
• pp.487-494
• /
• 2009

The purpose of this study was to investigate the feasibility of As(V) reduction by aqueous Fe(II), and subsequent As(III) immobilization by the precipitation of As(III) incorporated magnetite-like material [i.e., co-precipitation of As(III) with Fe(II) and Fe(III)]. Experimental results showed that homogeneous As(V) reduction did not occur by dissolved Fe(II) at various pH values although the thermodynamic calculation was in favor of the redox reaction between As(V) and Fe(II) under the given chemical conditions. Similarly, no heterogeneous reduction of sorbed As(V) by sorbed Fe(II) was observed using synthetic iron (oxy)hydroxide (Goethite, ${\alpha}$-FeOOH) at pH 7. Experimental results for the effect of As(V) on the oxidation of Fe(II) by dissolved oxygen showed that As(V) inhibited the oxidation of Fe(II). These results indicate that As(V) could be stable in the presence of Fe(II) under the anoxic or subsurface environments.