• The Korean Journal of Malacology
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• v.31 no.2
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• pp.151-158
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• 2015

This study was conducted to find out the changes of survival, respiration and organ structure of Tegillarca granosa exposed to copper (Cu). Experimental period was four weeks. Experimental groups were composed of one control condition and three copper exposure conditions (0.125, 0.250 and 0.500 mg/L). The results of the study confirmed that copper induces reduction of survival rate and respiration rate and histopathology of organ structure of the bivalve. In the copper concentration of 0.500 mg/L, mortality was 66.7% after Cu exposure of 4 weeks. Respiration rate was observed exposure groups lower than control decline by 18%. Histological analysis of organ system illustrated degeneration of epithelial layer and connective tissue layer of the mantle. Also, histological degenerations as epithelial atrophy and disappearance of lateral cilia are recognized in the gill and it was observed expansion of hemolymph sinus, disruption of epithelial layer, acidification of mucous and degeneration of muscle fiber bundles in the foot. In the digestive diverticulum, it was showed atrophy and destruction of basophilic cell and epithelial cell in the digestive tubules.

• Journal of Applied Biological Chemistry
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• v.57 no.1
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• pp.73-81
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• 2014

The present study was carried out to assess exposure and risk to thiophanate-methyl wettable powder for agricultural worker during mixing/loading and application with power sprayer in green pepper, cucumber and apple fields. Dermal exposure was measured with patches, gloves, socks and masks, while inhalation exposure was evaluated with personal air pump and solid sorbent. Those methods were full validated before experiment. During mixing/loading, dermal exposure amount in green pepper, cucumber and apple fields was $24.0{\pm}6.7$, $4.5{\pm}1.5$ and $18.5{\pm}0.6mg$, corresponding to mean 0.007, 0.001 and 0.005% of prepared active ingredient, respectively. The major exposed part for mixer/loader was hands (78-92%). Dermal exposure amount for applicator in green pepper, cucumber and apple fields was $84.9{\pm}14.0$, $34.0{\pm}20.8$ and $30.7{\pm}9.1mg$, corresponding to mean 0.024, 0.016 and 0.013% of applied active ingredient, respectively. The main body parts of exposure in apple field were hands, while thighs and shins in other fields. Inhalation exposure amount in green pepper, cucumber and apple fields was $1.5{\pm}2.2$, $52.7{\pm}48.9$ and $4.0{\pm}4.9{\mu}g$ during mixing/loading and $0.2{\pm}0.1$, $23.2{\pm}12.4$ and $0.4{\pm}0.6{\mu}g$ for applicator, respectively. These results were suggested that main factors affecting dermal exposure were contact frequency to the plants, foliage density, hygienic behavior, work type, and working environment, while inhalation exposure was affected mainly by working environment, especially wind. In risk assessment, margin of safety for thiophanate-methyl in all cases was over 1. However, during application in green pepper field, margin of safety was close to 1.

• 월간산업보건
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• s.273
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• pp.40-43
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• 2011

Perchloromethyl mercaptan에 대한 직업적 노출기준으로 TLV-TWA 0.1 ppm(0.76 mg/$m^3$)으로 권고한다. TLV-TWA 0.1 ppm(0.76 mg/$m^3$) 은 눈과 코의 자극 그리고 불쾌한 냄새로 인한 불편함의 가능성을 최소화하는 수준이다. Perchloromethyl mercaptan에 대한 동물 노출 실험연구와 근로자들의 노출연구 자료는 매우 제한적이다. 사고로 확인되지 않은 농도에 근로자들이 노출된 경우, 발견된 증상과 징후는 눈, 목, 가슴에 심한 자극과 기침, 눈물, 호흡곤란, 메스꺼움, 구토, 빈맥, 청색증, 경련 그리고 폐부종에 의한 사망이다. Perchloromethyl mercaptan을 활용하는 생산설비에서 TLV-TWA 0.1 ppm 이하 농도의 증기에 노출되었을 때 질병을 유발하였다는 보고는 없었다. 피부흡수, 발암성 그리고 TLV-STEL을 권고하기 위한 유용한 자료는 충분하지 않다.

• Journal of Soil and Groundwater Environment
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• v.9 no.1
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• pp.12-27
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• 2004

The contamination pattern of indoor air was simulated when groundwater dissolving benzene was used for household activities. Indoor exposure scenario consisted of inhalation, ingestion, and dermal absorption. Physiologically based pharmacokinetic (PBPK) model was used to analyze how benzene exposed to human body was distributed in internal organs. Main exposure pathways contributing total internal dose were inhalation and ingestion while the contribution of dermal absorption was very small. Man showed higher exposure rate than woman due to his higher breath rate. For a short-term exposure, benzene concentration in venous blood of SPT, RPT and liver changed rapidly while slowly did in venous blood of adipose tissue at a low concentration. For a long-term exposure, woman accumulated about 2.1 times higher than man. Most of benzene exposed to human body was removed by exhalation and metabolism at lung and liver, respectively. For inhalation and ingestion, the benzene removals by exhalation were 69.8 and 48.4%, respectively. Relative importance of removal mechanism was different according to the inflow displacement of benzene. The results obtained from this study would help understand exposure, distribution, and removal phenomena and make plans for the reduction of the health risk associated with the contaminated groundwater by various organic compounds.

• Proceedings of the KIEE Conference
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• 2008.04a
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• pp.139-140
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• 2008

휴대폰 전자파로 인해 두통, 불면증, 단기간의 기억력 소실 등의 신경 생리학적 증상을 호소하는 휴대론 전자파 과민증 (EHS, Electromagnetic Hypersensitivity) 환자들이 늘어나고 있다. 그러나 휴대폰 전자파 과민반응의 원인이 막연한 불안감 때문인지 혹은 전자파 노출로 인한 증상 인지에 대하여 확실하게 규명이 되지 않고 있다. GSM 방식의 휴대폰의 경우 전자파 노출 시 EHS 군을 대상으로 혈압, 맥박수 변화 등의 과민 반응에 대한 연구들이 수행되었으나 일반인과 EHS 군의 실험-대조군 연구로 생체신호, 자각증상 및 전자파 인지 여부에 대한 복합석인 연구와 CDMA 휴대폰 EHS 연구는 거의 없는 실정이다. 본 연구예서는 일반인 6명과 EHS 6명을 대상으로 30분간 300mW의 CDMA 휴대폰 전자파에 노출시 교감신경의 흥분을 나타내는 맥박, 호흡수, HRV(heart rate variability의 변화를 측정하였다. 그 결과, 일반인과 EHS 군 모두 전자파 노출여부에 따라 맥박, 호흡수, HRV의 변화가 없었다.

• The Korean Journal of Pesticide Science
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• v.16 no.4
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• pp.343-349
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• 2012

Exposure and risk assessments were conducted to evaluate the relative safety of mixing/loading work of indoxacarb between wettable powder (WP) and water dispersible granule (WG). Hand exposure was monitored using cotton gloves while inhalation exposure was measured using personal air monitor. Method validation for the exposure monitoring was established successfully through several experiments. Limit of determination and limit of quantitation were 0.25 and 1 ng, respectively. $R^2$ of calibration curve linearity was more than 0.9999 and reproducibility was 0.7-6. Recovery of indoxacarb from gloves, solid sorbent and glass fiber filter at three different levels was 81.5-108.8%. Trapping efficiency and breakthrough tests gave 981.5-108.8% of recovery. During mixing/loading procedure, hand exposure amount (75 percentile of 30 repetitions) for indoxacarb WP was 6 folds (459.8 mg/kg a.i) than that of WG (81.4 mg/kg a.i). This result indicates that WG has less drift than WP thanks to its granular type of formulation. Inhalation amount was $10^{-8}-10^{-7}%$ of spray mixture prepared and $10^{-4}-10^{-3}%$ of hand exposure. In inhalation case, no significant differences were observed between two formulations. Margin of safety was calculated for risk assessment using male Korean average body weight and acceptable operator exposure level as the important exposure factors. Mixing/loading procedures for both of the formulations were considered to be of least risk because calculated MOS values were more than 1.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2002.11a
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• pp.77-78
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• 2002

원자력시설이나 원자력발전소에서 사고가 발생하여 대기로 방출된 방사능물질은 두 가지 주요경로를 통해 인체노출이 일어난다 첫째는 지역내 대기중에 존재하는 방사성물질이 인체의 호흡이나 피부 등을 통해 체내로 흡입되는 직접적인 노출 (Direct Exposures)이고 다른 하나는 방사능물질이 대기로부터 주변의 토양에 침적하고 이러한 토양에서 재배된 오염된 농작물들 (쌀, 보리, 밀, 또는 과일, 채소)을 인간이 섭취하거나, 방사능물질에 오염된 목초로 키운 축산물(소, 돼지, 닭 등)과 이들로 생산하는 제품들(우유, 고기, 달걀 등)을 인간이 섭취함으로써 이루어지는 보다 간접적인 인체노출(Indirect Exposures)이 있을 수 있다. (중략)

• 월간산업보건
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• s.382
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• pp.11-14
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• 2020

눈, 피부 및 점막 자극의 가능성을 최소화하기 위해 옥시 염화인(phosphorus oxychloride)의 직업적 노출기준 TLV-TWA를 0.1ppm(0.63 mg/㎥)으로 권고하였다. 옥시 염화인 독성의 징후 및 증상으로는 두통, 현기증, 식욕 부진, 메스꺼움, 흉통 및 호흡 곤란이 있고 심한 급성 또는 반복 만성 노출에 의해서는 기관지 폐렴, 폐부종 그리고 신장 손상을 유발한다. 옥시 염화인은 물 또는 습한 공기에서 분해되어 염화수소와 인산을 형성한다. 피부, 감작제(SEN), 발암성 표기와 TLV-STEL을 권고하기에 충분한 자료가 없다.

• Journal of agricultural medicine and community health
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• v.29 no.2
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• pp.303-314
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• 2004

Objectives: This study was carried out to assess exposure levels of organic dusts and ammonia in poultry farms in Korea. Methods: A total of six poultry farms were investigated. The farms were located in Namwon, Chonlabuk-do and in Kae-San, Chungchongbuk-do. This study consisted of a questionnaire and measuring organic dusts and ammonia. The questionnaire included the characteristics of the farms, work patterns and the tasks of the poultry farms. Results and Conclusions: The farmers raised the chickens 45 times a year and the average number of years in the poultry farm were eight years ranging from 2 to 12 years. They worked for seven days per week and the average hours spent caring the chickens are 6.3 hours per day. The duration of staying in the confinement buildings was 3.3 hours per day. The work time in summer was longest. The feed and the water supply systems were automatic and the control of ventilation windows used "winch curtain" was semiautomatic. They used mechanical ventilation system in winter and used dilution ventilation system in the other seasons. The geometric mean concentration of total and respirable dust sampled in the poultry confinement buildings was 4.0 mg/$m^3$and 0.9 mg/$m^3$ respectively. The ratio of respirable to total dusts range from 9 to 49 percent. There was no sample exceeding the criteria 10 mg/$m^3$ for total dust and 3 mg/$m^3$ for respirable dust in farms. The criteria have been recommended by Korean Ministry of Labor and American Conference of Governmental Industrial Hygienist. The personal respirable dusts measured during a circle work averaged geometric mean concentration 1.4 mg/$m^3$ Two personal samples were exceeded the threshold 3 mg/$m^3$. There was a positive relation between an index and the personal samples of respirable dusts($R^2$=0.98). The index is calculated by multipling the total number of chickens in the farm by the age of the chickens and then dividing by the volume of the confinement building. The geometric mean concentration of area and personal ammonia samples was 23.3 ppm and 22.2 ppm, respectively. Some of the ammonia samples, both area and personal samples, exceeded the short term exposure limit value 35 ppm.

• The Korean Journal of Malacology
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• v.29 no.2
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• pp.129-137
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• 2013

This study was conducted to find out the changes of survivorship, respiration and organ structure of Mactra veneriformis exposed to copper (Cu). Experimental period was four weeks. Experimental groups were composed of one control condition and three copper exposure conditions (0.025, 0.050 and 0.100 mg/L). The results of the study confirmed that copper induces reduction of survival rate and respiration rate and histopathology of organ structure of the bivalve. In the copper concentration of 0.100 mg/L, mortality was 100% after Cu exposure of 3 weeks. Respiration rate was observed exposure groups lower than control decline by 75%. Histological analysis of organ system illustrated expansion of hemolymph sinus, disappearance of epidermal layer and degeneration of connective tissue layer of the mantle. Also, histological degenerations as epithelial necrosis and hyperplasia of mucous cells are recognized in the gill and it was observed expansion of hemolymph sinus, disruption of epithelial layer, decrease of mucous cell and degeneration of connective tissue layer in the foot. In the digestive diverticulum, it was showed atrophy of basophilic cell and degeneration of epithelial cell in the digestive tubules, and as the concentration of copper increased the accumulation of lipofuscin increased.