• Journal of Korean Society for Atmospheric Environment
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• v.26 no.3
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• pp.245-252
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• 2010

For the purpose of evaluating to remove elemental mercury using SCR (Selective Catalytic Reduction) catalysts, the result of the concentration variation of elemental mercury in lab experiment and field measurement was compared. The effect of the elemental mercury oxidation on commercial catalysts was studied in simulated gas. Three species of SCR catalyst, $V_2O_5-TiO_2$ type, were selected. The elemental mercury reduced 30% without HCl gas in SCR operating condition. But the width of reduction increased 60% at 20 ppm HCl gas. According to the result of field measurement, reduction rate of elemental mercury at SCR outlet showed 60%. The total mercury concentration decreased about 20%. The results were similar to the lab test. The results of chemical analysis of test sample showed increase of mercury concentration but surface change was not observed.

• The Journal of the Korean dental association
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• v.23 no.2 s.189
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• pp.161-164
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• 1985

This study was carried out for the purpose of evaluating the blood mercury concentration of dentists in Korea. Samples of blood were collected from 35 dentists during daily practice in November, 1984. The mercury level in the blood was measured by mercury analyses system (Sugiyama-Gen Environmental Science Co. LTD) The result obtained from this study ws the mean of total blood mercury level of dentists was 41.62 μg/100ml and the range 17.3μg/100ml~133.3μg/100ml.

• Composites Research
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• v.31 no.2
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• pp.76-81
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• 2018

In this study, the elemental mercury removal behaviors of silver-plated porous carbons materials were investigated. The pore structures and total pore volumes of the hybrid materials were analyzed by $N_2$ adsorption/desorption analysis at 77 K. The pore structures and surface morphologies of the hybrid materials were characterized by XRD and SEM, respectively. The elemental mercury adsorption capacities of all silver-plated porous carbons hybrid materials were higher than those of the as-received samples, despite the fact that the specific surface areas and total pore volumes decreased with increasing metal loading time. It was found that silver nanoparticles showed excellent elemental mercury removal behaviors in carbonaceous hybrid materials.

• Proceedings of the Korean Environmental Health Society Conference
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• 2005.12a
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• pp.4-15
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• 2005

Methylmercury (MeHg) is an environmental pollutant with neurotoxic effects on the central nervous system. The major exposure route of MeHg to humans is via consumption of fish and shellfish which accumulate the chemical through the food web in an aquatic environment. Hair mercury level is an excellent marker for MeHg exposure. We have been conducting a survey on hair mercury contents among general populations from 14 districts to estimate the current Japanese MeHg exposure level. Total mercury levels of all hair samples collected (12923 in total) were analyzed by the oxygen combustion-gold amalgamation method using an atomic absorption mercury detector. Multiple regression analysis revealed that mercury levels were significantly correlated with several covariates, such as sex, age, the amount of daily intake of total fish/shellfish, a preference for certain fish such as tuna or bonito, and artificial waving. The geometric means for the population without artificial waving were 2.47 and 1.65 ${\mu}g/g$ for males (n = 5623) and females (n = 3470), respectively. Hair mercury levels varied with age, and the variations were more significant in males. Since the difference between sexes was not evident at younger ages, some hormonal control might also be involved in the mercury uptake by human hair. The average mercury levels in our hair samples varied among the sampling districts. Tuna is a major carnivorous fish with high mercury accumulations that is often consumed in Japan. The amount of fish consumption and the preference rate far tuna would appear to be responsible far the regional variation in hair mercury levels in Japan. Recently, a provisional tolerable weekly intake (PTWI) of MeHg was revised by 61st JECFA to 1.6 ${\mu}g/kg/week$, which was about half that of the Japanese standard, and corresponded to a hair level of 2.2 ppm. The distribution of hair mercury levels in Japanese populations in the present study indicated that 25% of the Japanese females of child-bearing age were estimated to be exposed to MeHg over the PTWI level. This would reflect the high Japanese consumption of marine products. However, not only mercury contamination, but also the nutritional benefit may have to be considered when discussing the risk involved in the current level of fish and shellfish consumption in Japan.

• Environmental Engineering Research
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• v.10 no.6
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• pp.306-315
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• 2005

Total gas phase mercury (TGM) concentrations and event wet-only precipitation for Hg were collected for nine months (from April, 2002 to Dec., 2002) at Sterling, NY on the shoreline of Lake Ontario. TGM concentrations measured in this study ($3.02{\pm}2.14\;ng/m^3$) were in somewhat high range compared to other background sites. Using simplified quantitative transport bias analysis (SQTBA) possible sources affecting high Hg concentration in Sterling was identified, and they are coal-fired power plants located in southern NY and Pennsylvania. Wet deposition measured at Mercury Deposition Network (MDN) sites including Pt. Petre and Egbert, ON were compared with data obtained at the Sterling to estimate the total mercury wet deposition flux to Lake Ontario. The wet deposition flux was calculated to be the highest at the Sterling site ($7.94\;{\mu}g/m^2$ from April, 2002 to Dec. 2002) and the lowest at the Egbert ($3.92\;{\mu}g/m^2$), due to the both the difference in precipitation depth and Hg concentration in the precipitation. The deposition measured at the Sterling site is similar to Lake Michigan deposition of $6-14\;{\mu}g/m^2$ (converted for ninth months) measured for Lake Michigan Mass Balance Study (LMMBS).

• Journal of Preventive Medicine and Public Health
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• v.17 no.1
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• pp.217-221
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• 1984

In order to estimate interfering effects of mercury and lead on biochemical oxygen demand (BOD), BOD in 18 effluent samples were measured under three different concentrations of mercury and lead. The results obtained were as follows: 1. Biochemical oxygen demand(BOD) was decreased under the presence of mercury and lead, with parallel correlation of mercury concentration. 2. High correlations were noted between original BOD concentration and decreasing amount of BOD when concentrations of mercury or lead were increased. 3. When the lead concentration was high, the close correlation was observed between total organic carbon(TOC) and decreasing amount of BOD. 4. There was a negative correlation between TOC/BOD ratio and decreasing amount of BOD when the mercury concentrations were high.

• Journal of Korean Society for Atmospheric Environment
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• v.11 no.E
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• pp.55-62
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• 1995

The distribution of airborne mercury was investigated from several districts of Seoul, five other major cities and two rural areas during the period April, 1994 to March, 1995. The method used in this study involves absorption of gaseous mercury on CHromosorb$^R$ A coated with gold and detection by cold vapor atomic absorption spectroscopy. The atmospheric mercury concentrations in Seoul ranged from N.D. to 120.17 ng m$^3$ (mean 27.01 $\pm 9.42 ng m^{-3}, N=139$), while those in rural areas ranged from 1.72 to 8.24 ng $m^{-3} (mean 4.57 \pm 3.07 ng m^{-3}, N=5$). The spatial distribution characteristics of mercury distribution in urban air were examined by comparing mercury levels as a function of the distance from the urban center. Temporal distribution trends of airborne mercury were also studied using the monthly mean mercury data of various districts in Seoul. The atmospheric mercury concentration around Mokdong wastes incinerator in Seoul were also investigated.

• Carbon letters
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• v.15 no.4
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• pp.295-298
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• 2014

In this work, nanoporous carbons (NPCs) were prepared by the self-assembly of polymeric carbon precursors and block copolymer template in the presence of tetraethyl orthosilicate and colloidal silica. The NPCs' pore structures and total pore volumes were analyzed by reference to $N_2$/77 K adsorption isotherms. The porosity and elemental mercury adsorption of NPCs were increased by activation with carbon dioxide. It could be resulted that elemental mercury adsorption ability of NPCs depended on their specific surface area and micropore fraction.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.6
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• pp.693-703
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• 2008

The important source of the mercury in water-column is the influx of atmosphere mercury, via dry and wet deposition. In this study, wet deposition of mercury was estimated to be $14.56{\mu}g/m^2$ during 15 months at the Lake Soyang, which is a little higher than those observed in the several rural US Mercury Deposition Network (MDN) sites with similar precipitation depth. The mercury concentration in precipitation did not show a positive correlation with atmospheric RGM (reactive gaseous mercury) concentration, while maintaining good correlation with atmospheric $PM_{2.5}$ at Soyang Dam. This result suggests that the contribution of particulate Hg to the total Hg wet deposition should be more significant than that of RGM. In this study, both precipitation depth and precipitation type affected the amount of wet deposition and the concurrent mercury levels in precipitation. There was generally an inverse relationship between precipitation depth and Hg concentration in precipitation. Precipitation type was another factor that exerted controls on the Hg concentration in precipitation. As a result, the highest concentration of Hg was observed in snow, followed by in mixture (snow+rain) and in rain.

• Korean Journal of Community Nutrition
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• v.28 no.3
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• pp.192-205
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• 2023

Objectives: Previous studies have evaluated the association between mercury exposure and obesity but have yielded mixed conclusions. The aim of this study was to systematically review and summarize scientific evidence regarding the association between mercury exposure and obesity in the human population. Methods: We conducted a systematic search of PubMed, Web of Science, Scopus, and Science Direct for articles related to mercury exposure and obesity. Meta-analyses of the highest and lowest categories of mercury levels were evaluated using a random effects model. Begg's test was used to detect publication bias. Results: A total of 9 articles were included. The pooled random effects odds ratio (OR) for mercury exposure and obesity of all 9 studies was 1.66 (95% confidence interval [CI]: 1.16-2.38). This positive association was evident in adults (OR: 1.61, 95% CI: 1.02-2.54) and among studies with Asian populations (OR: 2.00, 95% CI: 1.53-2.59), but not among those with North America/African populations (OR: 0.90, 95% CI: 0.50-1.65). Conclusions: The present meta-analysis identified a positive association between mercury exposure and obesity. These findings suggest that toxic environmental metals such as mercury may be an important risk factor for obesity along with dietary habits and lifestyles.