• 한국산업보건학회지
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• 제15권1호
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• pp.27-35
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• 2005

This study was carried out to evaluate the characteristics of petroleum refinery workers' exposure to organic solvents. Exposure assessment was conducted by full shift-based long term personal sampling(TWA-P) and task-based short term personal sampling(STEL-P) strategy. Major organic solvents that workers can be exposed are various, varying from C3~C12, and this study focused on 11 kinds including benzene, considering toxicity and concentration level. In comparison with two sampling results, STEL-P shows a significant(p<0.001) excess of exposure level rather than TWA-P. As the potential risk index for benzene is calculated as 16, benzene should be set the highest priority for control in petroleum refinery industry. The tasks with the highest benzene exposure level were de-watering(AM;99.8 ppm), draining(AM;19.6ppm), sampling(AM;16.2ppm), and manual gauging(AM;15.02ppm). Petroleum refinery workers' exposure pattern to organic solvents differs by tasks performed, and some task has a high risk of temporary extreme exposure. Therefore, traditional 8-hour TWA sampling strategy have possibility of underestimation of exposure level of workers in petroleum refinery.

• Environmental Analysis Health and Toxicology
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• 제18권2호
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• pp.69-76
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• 2003

Effects of ambient nitrite, NO$_2$$\^$-/, at 1, 3, 10 and 30 mg/1, on the changes of plasma nitrite/nitrate and on hepatic drug - metabolizing enzyme activity were examined in the juvenile Israeli carp, Cyprinus carpio. When the fish were exposed to 1 and 3 mg/1 NO$_2$$\^$-/, there was an exposure duration-dependent increase in plasma NO$_2$$\^$-/ over the 96-hr period reaching 6∼7 fold excess the ambient concentration. In the fish exposed to 10 mg/1, a plateau concentration of less than 2-fold of the environment was attained in 12 hr. With 30 mg/1, however, the maximal plasma NO$_2$$\^$-/ was 41.25 mg/1 at 12 hr followed by a gradual decline. There was a concentration-dependent increase in methemoglobin (metHb) level in all NO$_2$$\^$-/ -exposed groups and a significant decrease in hematocrit value in 30 mg/l group after 96-hr exposure. Apart from the blunted increase in plasma NO$_2$$\^$-/ with higher NO$_2$$\^$-/ (10 and 30 mg/1) exposure, the ratio of plasma NO$_3$$\^$-/ to NO$_2$$\^$-/ was signifirantly higher in these groups compared to 1 and 3 mg/1. The imbalance in the plasma NO$_3$$\^$-//NO$_2$$\^$-/ at higher NO$_2$$\^$-/ exposure suggests a possible accelerated conversion of NO$_2$$\^$-/ to NO$_3$$\^$-/. Nitrite exposure did not affect the hepatic drug-metabolic activities in juvenile Israeli carp. All these data indicate that disposition of NO$_2$- differ depending upon exposed concentration and that metHb production may not be the exclusive toxic mechanism in carp.

• Journal of Preventive Medicine and Public Health
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• 제24권2호
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• pp.181-194
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• 1991

This study intended to obtain an useful information on the prevalence of subjective symptoms, and to clarify the interrelationships between blood lead and lead related symptoms in low level lead exposure. The 93 male workers exposed to lead and 56 male nonexposed workers were examined for their blood lead(PBB), Zinc-protoporphy(ZPP), hemoglobin(HB) and personnal history, and completed 15 questionnaires related to symptoms of lead absorption : also measured lead concentration in air (PBA) in the workplace. The results obtained were as follows ; 1. The means of blood lead (PBB), blood ZPP and hemoglobin (HB) among workers exposed to lead were $26.1{\pm}8.8{\mu}g/dl,\;28.3{\pm}26.0{\mu}g/dl$ and $16.2{\pm}1.2g/dl$ : whereas those of nonexposed workers were $18.7{\pm}5.1{\mu}g/dl,\;20.6{\pm}8.7{\mu}g/dl$ and $17.3{\pm}1.1g/dl$. The means of above three indicies between two groups showed significant difference statistically (p<0.05). 2. The means of blood lead (PBB), blood ZPP and hemoglobin of workers exposed .to different lead concentration in air were as follows : When it was below $25{\mu}g/m^3$, the indices were $24.7{\pm}79,\;26.1{\pm}26.8{\mu}g/dl\;and\;16.4{\pm}1.1g/dl$ respectively : These indices were $27.1{\pm}8.5,\;23.9{\pm}10.92{\mu}g/dl\;and\;16.2{\pm}1.3g/dl$ when the lead concentration in air was $25{\sim}50{\mu}g/m^3$ : and they were $3.4{\pm}9.3,\;42.3{\pm}31.3{\mu}g/dl\;and\;15.5{\pm}1.2g/dl$ when the concentration of lead was above $50{\mu}g/m^3$. Although there were statistical difference in blood lead and hemoglobin among three different lead concentration in air, there was no statistical difference of blood ZPP among the three groups with different exposure levels (p>0.05). 3. The most frequent by complained symptom was 'Generalized weakness and fatigue', and fewest symptom was 'Intermittent pains in abdomen' 4. Only two symptoms out of fifteen symptoms checked by themselves revealed significant difference between exposed and nonexposed groups. These were 'Intermittent pains of abdomen' and 'Joint pain or arthralgia' (p<0.05), No positive correlation was found between the levels of blood lead and symptom groups categorized as gastrointestinal, neuromuscular and constitutional symptoms, 5. Blood lead (r=0.3995) and ZPP (r=0.2837) showed statistically significant correlation with mean lead concentration in air, whereas correlations were not demonstrated between blood lead and lead related symptoms or blood ZPP and lead related symptoms. 6. Blood lead (PBB) and ZPP showed association (r=0.2466) and the equation PBB=23.75+0.0842 ZPP was derived. 7. On stepwise multiple regression, using blood lead level as a dependent variable and ZPP, hemoglobin (HB), age, work duration (WD) and symptom prevalence as a independent variables, only ZPP significantly contributed a lot to blood lead level. 8. While the ZPP measurement was found to be a good indicator in evaluating health effect of lead absorption in low level lead exposure, lead related symptoms were not sensitive enough to evaluate of lead absorption in low level exposure.

• 한국산업보건학회지
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• 제17권3호
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• pp.235-244
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• 2007

By comparing the proteins from the workers exposed to styrene with the ones from controls, it may be possible to identify proteins that play a role in the occurrence and progress of occupational disease and thus to study the molecular mechanisms of occupational disease. In order to find the biomarkers for assessing the styrene effects early, before clinical symptoms develop and to understand the mechanisms of adverse health effects, we surveyed 134 employees, among whom 52 workers(30 male and 22 female) were chronically exposed to styrene in 10 glass-reinforced plastic boat manufacturing factories in Korea and 82 controls had never been occupationally exposed to hazardous chemicals including styrene. The age and drinking habits and serum biochemistry such as total protein, BUN and serum creatinine in both groups were significantly different. Exposed workers were divided into three groups according to exposure levels of styrene(G1, below 1/2 TLV; G2, 1/2 TLV to TLV; G3, above TLV). The mean concentration of airborne styrene in G1 group was $10.93{\pm}11.33ppm$, and those of urinary mandelic acid(MA) and phenylglyoxylic acid(PGA) were $0.17{\pm}0.21$ and $0.13{\pm}0.11g/g$ creatinine, respectively. The mean concentration of airborne styrene in G2 and G3 groups were $47.54{\pm}22.43$ and $65.33{\pm}33.47ppm$, respectively, and levels of urinary metabolites such as MA and PGA increased considerably as expected with the increase in exposure level of styrene. The airborne styrene concentration were significantly correlated to the urinary concentration of MA(r=0.784, p=0.000) and PGA(r=0.626, p<0.001). In the 2D electrophoresis, the concentration of five proteins including complement C3 precursor, alpha-1-antitrypsin(AAT), vitamin D binding protein precursor(DBP), alpha-1-B-glycoprotein(A1BG) and inter alpha trypsin inhibitor(ITI) heavy chain-related protein were significantly altered in workers exposed to styrene compared with controls. While expression of complement C3 precursor and AAT increased by exposure to styrene, expression of DBP, A1BG and ITI heavy chain-related protein decreased. These results suggest that the exposure of styrene might affects levels of plasma proteinase, carriers of endogenous substances and immune system. In particular, increasing of AAT with the increase in exposure level of styrene can explain the tissue damage and inflammation by the imbalance of proteinase/antiproteinase and decrease of DBP, A1BG and ITI heavy chain-related protein in workers exposed to styrene is associated with dysfunction and/or declination in immune system and signal transduction

• 동아시아식생활학회지
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• 제7권1호
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• pp.41-46
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• 1997

Diet is generally accepted as one of the important factors in human cancer development. Ethyl carbamate has been associated with cancer for several decades and mainly found in the fermented beverages and foodstuff. The relationship between ethyl carbamate and the human health cannot be ignored especially in the areas where fermented foods consists of regular food consumption. To investigate the ethyl carbamate exposure level in Korean population, commercial fermented food samples were collected form local markets I Seoul area and home-made varieties were collected throughout the country. Following partial purification the concentration of ethyl carbamete was determined by GC/ MS. The concentration of ethyl carbamate ranged to 70 ppb in soysauce, to 10 ppb in soybean paste, and to 5 ppb in vinegars. Korean traditional alcoholic beverages showed small amount of ethyl carbamate. The estimated daily exposure of Korean population was 0~1900ng/day. It would be prudent to put efforts to minimize the formation of ethyl carbamate since the risk from the higher range exposure cannot be ignored.

• Yonsei Medical Journal
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• 제59권9호
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• pp.1123-1130
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• 2018

Purpose: Exposure to indoor radon is associated with lung cancer. This study aimed to estimate the number of lung cancer deaths attributable to indoor radon exposure, its burden of disease, and the effects of radon mitigation in Korea in 2010. Materials and Methods: Lung cancer deaths due to indoor radon exposure were estimated using exposure-response relations reported in previous studies. Years of life lost (YLLs) were calculated to quantify disease burden in relation to premature deaths. Mitigation effects were examined under scenarios in which all homes with indoor radon concentrations above a specified level were remediated below the level. Results: The estimated number of lung cancer deaths attributable to indoor radon exposure ranged from 1946 to 3863, accounting for 12.5-24.7% of 15623 total lung cancer deaths in 2010. YLLs due to premature deaths were estimated at 43140-101855 years (90-212 years per 100000 population). If all homes with radon levels above $148Bq/m^3$ are effectively remediated, 502-732 lung cancer deaths and 10972-18479 YLLs could be prevented. Conclusion: These findings suggest that indoor radon exposure contributes considerably to lung cancer, and that reducing indoor radon concentration would be helpful for decreasing the disease burden from lung cancer deaths.

• 농약과학회지
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• 제18권1호
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• pp.41-47
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• 2014

생체시료를 이용하여 화훼 농작업자와 플로리스트의 유기인계와 피레스로이드 살충제 노출 평가를 하였다. 유기인계는 소변중 DMP, DEP, DMTP, DETP를 피레스로이드계 살충제는 Cis/Trans DCCA, DBCA 그리고 3-PBA를 대상으로 평가 하였다. 연구 결과 DMP는 화훼 농작업자에서 가장 높았으며, 반면 DETP는 소매자에서 유의하게 높았다. 피레스로이드계 살충제의 대사물질은 3-PBA가 화훼 농작업자에서 통계적으로 유의하게 높았다. 화훼 농작업자는 살충제에 고농도로 노출됨을 알 수 있으며, 화훼를 대량으로 취급하는 도매상들도 살충제에 많이 노출됨을 알수 있었다.

• 한국환경보건학회지
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• 제26권4호
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• pp.21-28
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• 2000

Various man-made mineral fibers(MMMF) including refractory ceramic fiber(RCF) have been used widely in industries as insulation materials. The effect of fibrous dust on human health depends on fiber size, concentration (exposure level), and durability in biological system. Therefore, these parameters should be determined to evaluate accurately the potential risk of fibers on human health. The purpose of this study was to characterize the size of airborne fiber and the workers＇ exposure to airborne fibers in refractory ceramic fiber manufacturing and processing factories. Airborne fibers were collected on 25-mm mixed cellulose ester membrane filters at personal breathing zones, and analyzed by A and B counting rules of the National Institute for Occupational Safety and Health(NIOSH) Method # 7400. The average ratios of the fiber density by B rule to the fiber density by A rule was 0.84. This result indicates that the proportion of respirable fibers (<3 ${\mu}{\textrm}{m}$ diameter) in air samples was high. The average diameter and length of airborne fibers were 1.05${\mu}{\textrm}{m}$ and 35${\mu}{\textrm}{m}$, respectively. The average fiber concentrations (GM) of all personal samples was 0.26f/cc, and the average concentration was highest at blanket cutting and packing processes. The fifty seven percent of personal air samples was exceeded the proposed American Conference of Governmental Industrial Hygienists(ACGIH) Threshold Limit Value(TLV), i.e. 0.2 f/cc. It was concluded that the RCF industrial workers had the higher potential health risk due to small fiber diameter, long fiber length, and high exposure level to the airborne fibers.

• Environmental Analysis Health and Toxicology
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• 제17권2호
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• pp.135-140
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• 2002

넙치는 단기간 NaOCl에 대한 노출에 대해 2ppm이하에서는 육안적으로 관찰시 심각한 이상증상이 관찰되지 않았으며, 조피볼락에서는 2.5ppm까지 급성적으로 안전하였다. 넙치와 조피볼락에서의 1시간 LC$_{50}$은 각각 3.24ppm 및 7.58ppm이었다. 조피볼락을 NaOCl로 1시간 노출시키고 혈액학적 및 혈장생화학적 변수를 측정하였을 때 2ppm이상의 농도에서 glucose의 농도가 현저히 상승한 부분을 제외하고는 생화학적 변수에도 이상이 발견되지는 않았다. Glucose는 거의 모든 종류의 stress에 의해서 신속히 증가하는 변수로서 이 시험에서 발견된 증가현상도 NaOCl이 가진 냄새 또는 화학적 자극성에 의한 stress의 결과로 나타난 것으로 추정된다.

• 한국산업보건학회지
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• 제33권4호
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• pp.403-411
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• 2023

Objectives: Formalin is used as an anthelmintic in farms where flounder are raised. In this study, we aim to identify formaldehyde exposure levels for aquaculture industry workers and provide basic data for managing formaldehyde exposure. Methods: Exposure levels of formaldehyde in the air, including formalin spraying operations, were assessed separately for personal and area samples. In addition, considering the formalin administration method, dermal exposure to the hands was estimated when administering the chemical, and dermal exposure to the legs during water tank work was estimated by collecting water in the water tank and evaluating the amount of formaldehyde remaining. Finally, the respiratory exposure level and the estimated dermal exposure level were added to derive the total exposure level and compared with the maximum allowable human dose. Results: As a result of the airborne evaluation, the formaldehyde concentration of the worker (1 person) who performed the formalin spraying and flounder sorting was 33.61 ppb, and the arithmetic mean of formaldehyde concentrations of the workers (3 people) who only performed the flounder sorting was 3.28 ppb (range: 2.25-4.89 ppb). In the case of dermal exposure, when spraying formalin once, the amount was estimated to be 0.33-2.62 mg when wearing protective gear and 3.27-26.12 mg when not wearing it. Conclusions: There was a difference in the formaldehyde exposure level of workers depending on their operation of handling formalin and whether or not protective gear was worn. In particular, because the level of formaldehyde exposure due to dermal exposure can be significant, there is a need to improve formalin administration methods in a way that avoids skin contact as much as possible.