• Journal of Environmental Science International
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• v.1 no.1
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• pp.1.1-11
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• 1992

To find heavy metal-specific effects on the photosynthetic apparatus of higher plants, we investigated effects of $CuCl_2$, HgCl_2$ and $ZnCl_2$ on electron transport activity and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings. Effects on some related processes such as germination, growth and photosynthetic pigments of the test plants were also studied. Germination and growth rate were inhibited in a concentration-dependent manner by these metals. Mercury was shown to be the most potent inhibitor of germination, growth and biosynthesis of photosynthetic pigments of barley plants. In the inhibition of electron transport activity, quantum yield of PS II, and chlorophyll fluorescence induction kinetics of chloroplasts isolated from barley seedlings, mercury chloride showed more pronounced effects than other two metals. Contrary to the effects of other two metals, mercury chloride increased variable fluorescence significantly and abolished qE in the fluorescence induction kinetics from broken chloroplasts of barley seedlings. This increase in variable fluorescence is due to the inhibition of the electron transport chain after PS ll and the following dark reactions. The inhibition of qE could be attributed to the interruption of pH formation and do-epoxidation of violaxathin to zeaxanthin in thylakoids by mercury. This unique effect of mercury on chlorophyll fluorescence induction pattern could be used as a good indicator for testing the presence and/or the concentration of mercury in the samples contaminated with heavy metals.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.1
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• pp.62-67
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• 1993

This study aims at investigating the relationships between the urinary mercury concentration and blood zinc-protoportphyrin, serum cholinestrase activity, making 149 workers exposed to mercury vapor and 68 workers who were not exposed to mercury among the workers in a flurorescent lamp manufactureing factory an object of this investigation. The results are as follows ; 1. In an exposed group the number of those whose urinary mercury concentration showed over $100{\mu}g/l$ was 21 persons (14.3%) among 147 workers. The average urinary mercury concentration was $52.1{\pm}46.1{\mu}g/l$($1.8-361.2{\mu}g/l$), which proved to be higher than the average concentration in a control group. 2. In an exposed group, the average concentration of blood zinc-protoporphyrin was $27.8{\pm}12.5{\mu}g/dl$($12.2-101.5{\mu}g/dl$), which proved to be somewhat higher than the average concentration in a control group. But it did not show a significant difference. 3. In an exposed group, the average concentration of serum cholinesterase activity showed $1936.7{\pm}341.0IU/l$(1,120,0-2,8750IU/l), which proved to be lower than the average concentration in a control group. 4. The relational coefficient between urinary mercury concentration and blool zinc-protoporphyrin, serum cholinesterase activity of the whole workers exposed to mercury showed little difference. While the relational coefficient between the urinary mercury concentration and blood zinc-protoporphyrin of the workers whose urinary mercury concentration showed over $100{\mu}g/l$ was relatively high, which was 0.62.

• Journal of Environmental Policy
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• v.14 no.1
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• pp.135-158
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• 2015

An efficient management system of mercury-containing waste was designed by reviewing the management and treatment of spent fluorescent lamp in Korea and foreign countries. According to Waste Management Act in Korea, mercury-containing wastes from households are classified as municipal solid wastes even though mercury-containing wastes pose hazardous risks. In general, hence, mercury-containing wastes from households are not being managed properly because those wastes from households were not classified as specific wastes (or hazardous wastes). Some mercury-containing wastes are managed as a mandatory target item in waste charge system and Extended Producer Responsibility (EPR) system under Act on Promotion for Saving and Recycling of Resources. An efficient management plan of mercury-containing wastes can be derived with an improved collection system, designating disposal sites and advanced treatment facilities for spent fluorescent lamps. Finally, the role of each agent involved from collection to disposal of mercury-containing wastes was suggested to establish the efficient management system for mercury-containing waste.

• Journal of Environmental Health Sciences
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• v.35 no.4
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• pp.287-294
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• 2009

This study analysed the mercury concentration in the hair of 62 students (male : 21, female : 41) of D university in Najusi, Jeon-Nam area. Also, questionnaire, which developed by NIES, were completed by the students. According to the questionnaire, most of the students had a higher intake of meat than that of fish. Also, among the students, there were many smokes and many had dental treatment with amalgam. Based on the gender, female showed 1.024 ${\mu}g/g$ and male showed 0.882 ${\mu}g/g$ of the mercury concentration. This means that female students had higher level of mercury in their hair, but it was not a significant statistic difference. Comparing by the intake frequency of meat, processed food stuffs, protein foods, it shows the more they at the higher mercury concentration was observed. According to the intake frequency of fish, when the number of times they intake increased, the mercury concentration was higher. Under one time was 0.857 ${\mu}g/g$ and twice or more times were 1.152 ${\mu}g/g$, which showed a significant statistical difference (p<0.05). Depending on the Life style, the mercury concentration in the hair was high with workout, outdoor activities, and direct smoking. The mercury concentration in the hair showed no difference for whether they received amalgam treatment but the personal dietary habit and the Living condition affects strongly on the mercury concentration level.

• Journal of Environmental Health Sciences
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• v.44 no.1
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• pp.24-30
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• 2018

Objectives: Based on the amount of amalgam, the duration of exposure, and the water pH, this study aims to investigate the change patterns in the mercury concentrations in water after amalgams have been introduced into sewage water. It is expected that the study results will be useful in improving the system for regulating the amount of mercury that is introduced into the environment. Methods: During the study, a glass test-tube with a cap was washed and disinfected using the glass laboratory device washing method. Then, 1, 2, 3, and 4 tabs were placed into a 10 mL pH 4 solution and 10 mL pH 7 distilled water. Each specimen was prepared in duplicate. The mean of the two mercury concentrations was used as the representative value, and the mercury concentration was measured using a mercury measurement device (DMA-80, Milestone, Italy) a total of eight times at one-week intervals. Results: The results show that the lower was the pH, the higher was the amount of amalgam. Also the longer was the duration, the more significant was the increase of mercury concentration in the water. Conclusions: Dental clinics are collected separately from dental clinics that used them. Given this, dental clinics in Korea must have the necessary facilities to separately collect mercury at their level. In addition, proper disposal systems and social attention to the proper management of dental wastes are required to prevent environmental pollution from mercury.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.21 no.2
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• pp.90-98
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• 2011

Objectives: The aim of this study was to evaluate the level of urinary mercury and analyze which factors would affect urinary mercury concentration among dental hygienists in dental clinics. Methods: This study conducted by questionnaire and detection of urinary mercury concentration of 268 dental hygienists working in dental clinics from July to August of 2009. Data collected from two hundred and thirty-five dental hygienists were analyzed by the geometric mean (GM). Analytical results of urine samples with less than 0.3 g creatinine/L and greater than 3g creatinine/L were excluded from statistical analysis. Results: Urinary mercury concentration of 235 dental hygienists showed the geometric distribution. The arithmetic and geometric means of urinary mercury concentration were $0.996{\mu}g/g$ creatinine and $0.755{\mu}g/g$ creatinine, respectively. From multiple regression analysis, the number of amalgam filling, the consumption frequency of raw fish and the number of amalgam handling in current workplace was revealed as increasing factors of urinary mercury concentration. Conclusions: The level of urinary mercury in dental hygienists was higher than in general Korean population. The number of amalgam filling, the consumption frequency of raw fish and the number of amalgam handling in current workplace was revealed as increasing factors of urinary mercury concentration. Therefore using resin materials instead of amalgam in dental clinics is highly desirable.

• Journal of Yeungnam Medical Science
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• v.40 no.4
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• pp.373-380
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• 2023

Background: The association between dental amalgam fillings and urine mercury concentrations was investigated in this study to assess the health risks associated with dental amalgams. Methods: This cross-sectional study included 99 women in their 20s who visited the dental clinic in Daegu, Korea. The 99 participants were composed of 68 subjects who had dental amalgam fillings (exposure group) and 31 subjects who did not have dental amalgam fillings (nonexposure group). Oral examinations were conducted by a single dental hygienist, sociodemographic features were investigated as confounding variables, and urine mercury concentrations were measured using an automatic mercury analyzer. Results: The mean±standard deviation of the urine mercury concentrations of the exposure and nonexposure groups were 1.50±1.78 ㎍/g creatinine and 0.53±0.63 ㎍/g creatinine, respectively. The exposure group showed significantly higher levels than the nonexposure group (p<0.01). The urine mercury concentration significantly increased with an increase in the number of teeth filled with amalgam, cavity surfaces involved, and number of defective amalgam fillings, and according to the latest exposure time (p<0.001). In the multiple regression analysis of amalgam-related factors and urine mercury concentrations after correction for confounding factors, the urine mercury concentration in the group with six or more amalgam-filled teeth, 11 or more cavity surfaces, and two or more defective amalgams was significantly higher than that in the nonexposure group (p<0.001). Conclusion: According to this study, exposure to dental amalgams was confirmed to significantly affect urine mercury concentrations.

• 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.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.411-418
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• 2004

Mercury, one of the most diffused and hazardous organ-specific environmental contaminants, exists in a wide variety of physical and chemical states. The murcury with the nature which evaporates easily can cause an acute or chronic mercury poisoning to workers at mercury-handling workplaces. Although many studies indicate that mercury induces a deleterious damage, little has been reported from the investigations of mercury effects at surrounding levels in living things. The purpose of this study was to evaluate the biological effects of mercury chloride and ionizing radiation. Prepubertal male F344 rats were administered mercury chloride in drinking water throughout the experimental period or were given wholebody irradiation with a dose of 6.5 Gy. The amount changed of body weight during the experimental period showed a 4.9% rise in the mercury-treated group and 14.4% decline in the irradiated group compared with the level of the control group. The results of hematological analysis (red blood cells, white blood cells, hemoglobin, and hematocrit) indicated the differential effects of mercury chloride and ionizing radiation. However the concentration of cortisol as assessed by radioimmunoassay increased in both of the groups. Relative expressions of mRNA related to mitochondrion-mediated apoptosis were investigated using semiquantitative reverse transcription polymerase chain reaction on gonad and urinary organs of the experimental groups. While the expression of Bcl-2 mRNA exhibited different patterns depending on the organs or the experimental groups, both of the experimental groups showed a conspicuous expressions of Bax mRNA. In conclusion, the target organ of mercury chloride seems to be a urinary organ and the pattern of damage induced by mercury chloride differs from that by ionizing radiation.

• Journal of environmental and Sanitary engineering
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• v.15 no.3
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• pp.8-14
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• 2000

This paper was conducted to examine the level of total and organic mercury in the scalp hair by the consumption pattern of fish. The scalp hair samples were collected from the occipital part of 101 in coastal, 106 in rural. The total and organic mercury contents of adult scalp hair increased with age up to the forties and slightly decreased in the fifties. (p<0.01) The mercury contents of the persons who were favorite dishes of fish were most high, and who prefer fish were 2 times higher than those of the persons who prefer vegetables and broiled. The contents of total and organic mercury in scalp hair showed a increasing tendency with the intake frequency of raw and cooked fish. (p<0.01) The total and organic mercury contents in the raw fishes were over 2 times higher than those in the boiled fishes.