• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.3 no.1
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• pp.78-90
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• 1993

This study was designed obtain and early detection the workers exposed to excessive copper dust and also to present biological exposure index. The exposed group consisted of 62 male workers at the metallurgy workplaces. To evaluate the degree of individual exposure the copper dust, each personal air sampling was collected. Biological exposures in the exposed group was quantified for the blood and urine copper levels using flameless atomic absorption spectrophotometer. The control group consisted of 70 male adults with the history of nonexposure to copper by the inhalation occupationally. The average concentration of copper in blood and urine of the exposed group was $49.44{\pm}8.90(29.05-80.63){\mu}g/dl$, $39.99{\pm}11.04(29.62-80.63){\mu}g/l$ respectively. The average concentration of air borne copper was $0.48{\pm}0.31(0.03-1.18)mg/m^3$. The average concentration of blood and urine copper in the control group was $42.93{\pm}5.84(25.05-57.85){\mu}g/dl$, $33.02{\pm}13.38(12.00-82.05){\mu}g/l$ respectively. The difference observed in the average concentration of blood and urine copper of the exposed and control groups was statistically significant seperately (blood copper, p<0.05 ; urine copper, p<0.05). The relationship between the individual exposure concentration of air borne copper and the concentration of the blood and urine copper was statistically significant, respectively (blood copper, r=0.54, p<0.05 ; urine copper, r=0.37, p<0.05). The relationship between the working duration and the concentration of blood and urine was not statistically significant respectively (blood copper, r=0.14 ; urine copper, r=0.12). The relationship between the age and the concentration of blood and urine copper was statistically not significant respectively (blood copper, r=013 ; urine copper, r=-0.06). The relationship between blood and urine copper concentration in the exposed group was statistically significant (r=0.62, p<0.05), and the relationship between blood and urine copper concentration in the control group was also statistically significant (r=0.39, p<0.05).

• Journal of Embryo Transfer
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• v.19 no.1
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• pp.35-42
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• 2004

The purpose of this study was to evaluate the effects of Cytochalasin B treatment on the survivability The different concentration and exposed times of CB of porcine embryos frozen by vitrification were observed. The results were summarized as follows ; 1. The survivability rates of the porcine embryos treated CB(60.5%) were significantly higher than non-treated(32.8%)(p＜0.1). However the recovered with normal morphology rates(84.2%) were no significantly different than non-treated(81.9%). 2. We observed by different concentration of CB treatment, the group of CB treated with 7.5 $\mu\textrm{g}$/$m\ell$ were significantly showed a higher of normal morphology(44/45; 98%) and viability rate(33/45;73%) than other groups(morphology: 65∼70%, viability: 15∼74%)(p<0.05). While the control was lower as 70% of morphology and 38% of viability. 3. We examined exposed time of in-vitro CB treated embryos, the group of more than 20 minutes exposed were significantly were observed a higher rates of normal morphology and viability(p<0.05). And the group of 13 minutes, 14,000 rpm centrifuged(64%) were significantly higher than non-centrifuged(36%). Survivability of porcine embryos were improved in CB treated group. It suggested that 7.5 $\mu\textrm{g}$/$m\ell$ concentration of CB treatment, 20 minutes exposed times and 13 minutes, 14000 rpm centrifuged prior to vitrification improve normal morphology and survivability rates.

• Environmental Analysis Health and Toxicology
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• v.17 no.4
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• pp.357-362
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• 2002

Tests for the toxicity of tributyltin (TBT) were conducted on mysid collected from Dadepo beach, Pusan, Korea. The toxic effects of tributyltin on the survival, growth and oxygen consumption of the mysid, Neomysis awatschensis have been evaluated. Mysids were exposed to several concentrations of TBT (0, 0.56, 1.15, 3.07 and 6.12 $\mu\textrm{g}$/L) for 6 weeks. Survival rate was decreased with increases in concentration and exposure time and the reduction of more than 40％ occurred at TBT concentration greater than 1.15 $\mu\textrm{g}$/L after 6 weeks. Growth rate was significantly decreased at concentrations greater than 1.15 $\mu\textrm{g}$/L. Oxygen consumption rate was also decreased in a concentration-dependent way and significantly decreased to 39,47 and 69％ of the control at 1.15, 3.07 and 6.12 $\mu\textrm{g}$/L, respectively. These results indicate that the contamination of aquatic environment by TBT has the potential to significantly reduce coastal and estuaries recruitment of mysids.

• Safety and Health at Work
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• v.9 no.3
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• pp.356-359
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• 2018

This case report attempts to present a case of acute toxic hepatitis in fire extinguisher manufacturing workers exposed to 2,2-dichloro-1,1,1-trifluoro-ethane (HCFC-123) in August 2017 in Korea. Twenty-two-year-old male workers were exposed to HCFC-123 for 1.5 hours one day and for 2.5 hours the other day, after which one worker died, and the other recovered after treatment. The workers were diagnosed with acute toxicity of hepatitis. However, exposure levels of HCFC-123 were not known with no work environment measurement done. Therefore, this study was conducted to estimate the exposure concentration of HCFC-123 via a job simulation experiment. In the simulation, the HCFC-123 exposure concentration was measured with the same working practice and working time as with the workers aforementioned. As a result, the workers who infused HCFC-123 into storage tanks were estimated to be exposed to HCFC-123 at a concentration of $20.65{\pm}10.81ppm$, and a mean concentration of area samples within a working radius were estimated as $70.30{\pm}18.10ppm$. Valve assembly workers working on valves of a fire extinguisher filled with HCFC-123 were exposed to HCFC-123 at concentrations of $91.65{\pm}4.03ppm$ and $115.55{\pm}7.28ppm$, respectively, in the simulation, and area samples simulated within the working radius were also found to be high with concentrations of $122.75{\pm}91.15ppm$ and $126.80{\pm}60.25ppm$, respectively. Nitrogen gas packing workers, who did not handle HCFC-123 directly, were exposed to the agent at a concentration of $71.80{\pm}8.49ppm$. These results suggest that exposure to HCFC-123 at high concentrations for 1.5-2.5 hours caused acute toxic hepatitis in two workers.

• Journal of Nutrition and Health
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• v.32 no.4
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• pp.353-368
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• 1999

This study was performed to investigate the effects of Korean native plant diets on lipid and cadmium (Cd) metabolisms and also antioxidative enzyme activities in rats. Seventy male Sprague-Dawley rats weighing 210.3$\pm$2.7g were blocked into ten groups according to body weight. Rats were raised for four weeks with diets containing 0 or 0.04%(w/w) cadmium chloride and 5%(w/w) plant powder-Ssook(Artemisia princeps var. orientalis HARA), Chamchwi(Aster scaber THUNB), Gomchwi(Lingularia fischeri TUBCZ). or Solbeerum (Portulaca oleracea LINNE). Food intake, weight gain, food efficiency ratio, and weights of liver, kidney, spleen and epididymal fat were significantly lower in Cd-exposed groups, food efficiency ratio, and weights of liver, kidney, spleen and epididymal fat were significanlty lower in Cd-exposed groups. Plasma total lipid level, liver total lipid, cholesterol and triglycerde concentrations, and fecal total lipid, cholesterol and triglyceride excretions were decreased by Cd administration. Total lipid and triglyceride concentration in plasma and liver were lower in Chamchwi groups together with increased fecal total lipid and triglyceride excretions. Cholesterol concentration in plasma and liver were lower in Gomchwi groups with increased fecal cholesterol excretions. Activities of red-blood-cell superoxide dismutase(SOD), and liver catalase, SOD and glutathione peroxidase (GSH-px) were decreased significantly by Cd administration. Thiobarbituric acid reactive substance(TBARS) concentrations of plasma and liver were increased by Cd administration. Thiobarbituric acid reactive substance(TBARS) concentration of plasma and liver were increased by Cd administration. Administration of plant diets decreased plasma and liver catalase, SOD and GSH-px activities in Cd-free diet groups and increased them in Cd-administered groups. Plasma and liver TBARS concentrations were decreased in animals fed plant diets, with Chamchwi showing the most effective antioxidative capacity. The concentration of Cd accumulated in blood and tissue decreased in Cd-exposed groups fed plant diets. Liver Cd concentration were lower in the Chamchwi and Gomchwi groups, and kidney Cd levels were lower in the Ssook and Chamchwi groups. Among them, Chamchwi was the most effective in Cd detoxification. In conclusion, Chamchwi and Gomchwi were effective in lowering tissue lipid levels, with Chamchwi having the greatest antioxidative and detoxifying effects.

• Journal of Preventive Medicine and Public Health
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• v.28 no.2 s.50
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• pp.406-420
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• 1995

To study the health hazards and exposure status of manganese among female manganese workers, authors conducted airborne, blood and urine manganese concentration measurements, questionnaire and neurological examinations on 80 manganese-handling productive female workers(exposed group) in a manganese manufacturing facto in Pohang city and 127 productive female workers not handling manganese(control group) in other factories in the Pohang city. The results are; 1. Geometric mean concentrations of manganese in air and urine were $0.98mg/m^3\;and\;4.12{\mu}g/l$ and arithmetic mean concentration of manganese in blood was $6.94{\mu}g/dl$ in exposed group, significantly higher than those of control group(p<0.05). However, clinical and laboratory findings in exposed group were not statistically different from those of control group. 2. As age increase, positive rates of clinical symptoms also increased in the exposed group. However, in older aged group, the positive rates of symptoms and signs were statistically different from those of control group. We observed the same tendency in the positive rates of the neurological examinations. 3. There was statistically significant correlation between airborne and urine manganese concentrations(r=0.61, p<0.01) while there was no statistically significant correlation between airborne and blood manganese concentrations(r=0.29, p>0.05). The results suggest that urine manganese concentration was the best appropriate biomarker to estimate the exposure to manganese in respect to clinical symptoms and signs. In the analysis of correlation between urine and airborne manganese concentrations, it is required to adjust the present permissible exposure level(PEL) of airborne manganese.

• The Korean Journal of Food And Nutrition
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• v.27 no.5
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• pp.845-850
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• 2014

In the present study, the effects of extracts from Korean plants on the DNA damage response in HaCaT cells exposed to ultraviolet B (UVB) were investigated. The activity of cells treated for 24 hr with ethanol extracts from Vaccinium spp. (VS), and Vitis vinifera L (VV) alone was similar to that of the non-treated control, but gradually decreased at concentrations above $200{\mu}g/mL$. However, when post-incubation of UVB-exposed cells was carried out for 24 hr in medium containing VS or VV extracts, the cell activity increased in a concentration-dependent manner compared with that in the normal growth medium. The cell viability of UVB-exposed cells also increased when post-incubated in medium containing VS or VV extracts, in a concentration-dependent manner. Nuclear fragmentation analysis showed that post-incubation with VS or VV extracts decreased the UVB-induced apoptosis by about 10 and 13%, respectively, of that in cells post-incubated in growth medium. After 24 hr of post-incubation in medium containing VS or VV extracts, the level of CPD and 8-OHdG decreased in time- and concentration-dependent manners. Overall these results suggest that VS and VV extracts assist the survival of UVB-exposed cells, in accordance with the respective decrease in the levels of UVB-induced DNA damage.

• Journal of People, Plants, and Environment
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• v.22 no.2
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• pp.127-143
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• 2019

This study investigates the color stimuli of two varieties of foliage plants by extracting electroencephalogram, electrocardiogram and physiology activity data from 30 participants in their 50s or older. Changes in the physiological activity of subjects against six color stimuli were examined. The stimulus to real green plants 'Silver Queen' was set as the control group, and was compared with other groups including the stimulus to real 'Angel' plants and four stimuli to artificial colors (two color images and color schemes of the same green and red plants). Compared to the five groups, the relative theta power spectrum (RT) and the ratio of alpha to high beta (RAHB) increased in the subjects exposed to real green plants. This result demonstrates that the green plant ('Silver Queen') increases the stability, relaxation, and internal concentration of subjects in a proper state of awakening. The result of this experiment showed a statistically significant difference in the level of RT when subjects were exposed to the groups of real green and red plants. This finding indicates that the green plant increases internal concentration more than the red plant. RT and the relative low beta power spectrum (RLB) in the groups of natural colors were higher than the groups of artificial colors when subjects focused their mind on the two types of real plants. However, the level of relative mid beta power spectrum (RMB), ratio of SMR to theta (RST), ratio of mid beta to theta (RMT), relative high beta power spectrum (RHB), and spectral edge frequency 95% were higher when subjects were exposed to the photos and colors scheme of plants than when they were exposed to real plants. The subjects experienced more "comfortable" emotions when they were looking at plants with green colors. Overall, it is recommended to use the natural colors of real plants in places where which stability and relaxation are required. On the contrary, the artificial colors of plants such as their photos and color schemes are useful in places where a high level of concentration is required in a short period of time.

• Nutrition Research and Practice
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• v.3 no.1
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• pp.15-22
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• 2009

This study was performed to investigate the effect of chlorella on cadmium (Cd) toxicity in Cd-administered rats. Sixty male Sprague-Dawley rats (14 week-old) were blocked into 6 groups. Cadmium chloride was given at levels of 0 or 325 mg (Cd: 0, 160 ppm), and chlorella powder at levels of 0, 3 and 5%. Cadmium was accumulated in blood and tissues (liver, kidney and small intestine) in the Cd-exposed groups, while the accumulation of Cd was decreased in the Cd-exposed chlorella groups. Fecal and urinary Cd excretions were remarkably increased in Cd-exposed chlorella groups. Thus, cadmium retention ratio and absorption rate were decreased in the Cd exposed chlorella groups. Urinary and serum creatinine, and creatinine clearance were not changed in experimental animals. In addition, metallothionein (MT) synthesis in tissues was increased by Cd administration. The Cd-exposed chlorella groups indicated lower MT concentration compared to the Cd-exposed groups. Moreover, glomerular filtration rate (GFR) was not changed by dietary chI orella and Cd administration. According to the results above, this study could suggest that Cd toxicity can be alleviated by increasing Cd excretion through feces. Therefore, when exposed to Cd, chlorella is an appropriate source which counteracts heavy metal poisoning, to decrease the damage of tissues by decreasing cadmium absorption.

• Journal of fish pathology
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• v.14 no.1
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• pp.37-45
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• 2001

This study was carried out to determine the effects of various iron concentrations on the hemochemical changes of olive flounder, Paralichthys olivaceus exposed for 50 days. The flounder exposed to iron concentration 0.97 mg/$\ell$ started to increase significantly in serum iron and magnesium concentrations after 20 days. The low concentration of serum calcium concentration was observed at 30 days of the experiment in iron concentration 0.97 mg/$\ell$. Serum total protein, albumin and glucose concentrations initiated to decrease from 30 days at the iron concentrations of 0.97 mg/$\ell$ or up. Total cholesterol concentration was increased significantly after 40 days at iron concentration 0.97 mg/$\ell$. A significant increment of GOT, GPT and LDH activities in the flounder serum was noticed after 40 days at iron concentrations over 0.97 mg/$\ell$ without significant changes of Al-P. These results indicate that flounder can be affected by iron in terms of inorganic elements, organic substances and enzyme activity in serum when they were exposed to the iron concentrations 0.97 mg/$\ell$ or higher for 30 days.