Park, Hee Lyun;Lee, Nae Woo;Kim, Sung Bin;Pisaniello, Dino L.
Journal of Korean Society of Occupational and Environmental Hygiene
/
v.10
no.2
/
pp.68-77
/
2000
This study was performed to evaluate tannin exposure by wooddusts for workers in furniture factories and to investigate the relationship between tannin exposure and sino-nasal cancer risk. In order to explore possible cytological changes leading to nasal cancer, we have examined 50 male furniture workers and 50 matched controls using brush cytology. The results we have obtained in this study were as follows: 1. The tannin contents of woods used in woodworking factories have been measured and varied from 0.43 to 8.72 mg tannic acid equivalent per gram wood, for reconstituted softwood and turpentine (Syncarpia glomuliferia) respectively. 2. Airborne tannins in wooddusts were also determined by area and personal exposure. The values of mean exposures for both methods are ranged from 3.1 to $5.0{\mu}g/m^3$ and from 4.6 to $14.5{\mu}g/m^3$ in furniture manufactures. 3. Over nasal cytology scores 2, the scores of study group were slightly more than control group and this kind of metaplasias seemed to be occurred over $2mg/m^3$ wooddust and $6{\mu}g/m^3$ tannin exposure. Keratinising squamous metaplasia was investigated at nasal cytology score 3 and $10{\mu}g/m^3$ tannin exposure. The nasal cytology score 4 was seemed to be atypical squamous metaplasia. 4. To find out contributing factors to nasal cytology change, odds ratio that is one of fundmental biostatistics was applied. Actually the relationship between wooddust, tannin concentration and metaplasia were not meaningful, but the relationship between working experence more than 15 years and metaplasia was calculated as 1.83. This reveals that significant clinical abnormalities could be influenced from the years of woodworking experiences. However further research is required to evaluate the significance of the data, for the purposes of sino-nasal risk assessment, standard setting to prevent nasal cancer occurrences and possibility of changing workplace.
Proceedings of the Korean Environmental Health Society Conference
/
2002.04a
/
pp.40.1-43
/
2002
The purpose of this study was to evaluate a new sampling and analytical method for the determination of hexavalent chromium, Cr(VI) in mist from field plating operation. The Procedures of this new method (Shin & Paik's Method) are as the following: Airborne hexavalent chromium is collected on polyvinyl chloride (PVC) filter according to the National Institute for Occupational Safety and Health (NIOSH) Method 7600, and the filter sample is placed in a screw-capped vial and soaked with 2% NaOH/3% Na₂CO₃ solution immediately after sampling. The Cr(VI) sample is analyzed by ion chromatography/visible spectrophotometry (IC/VS) according to the U.S. Environmental Protection Agency (EPA) Method 218.6. The airborne Cr(VI) concentrations measured by this method were compared with those determined by three reference methods: One (NIOSH/EPA Method) consisted of sampling airborne Cr(VI) on PVC filters and storing the sample filters in screw-capped vials according to the NIOSH method, and analyzing Cr(VI) in samples using IC/VS according to the EPA method. The second method (Impinger Method/NaHCO₃) consisted of absorbing airborne Cr(VI) into 0.02 MN/sub a/Hco₃ solution in midget impinger, and analyzing the Cr(VI) in samples using IC/VS. The third method was the OSHA Method Id-215. Using these four different methods, four replicates of air samples were collected at an electroplating process and analyzed simultaneously. Two-way ANOVA and Paired t-test were used to test difference among values determined by the methods. There was no significant difference and a strong correlation (r/sup 2/=0.99) between Cr(VI) concentrations measured by the shin & Paik's Method and an impinger method (p>0.05). However, Cr(VI) concentrations determined by Shin & Paik's Method were Significantly different form those by the NIOSH/EPA Method (p<0.05) or the OSHA method (p<0.05). The Cr(VI) concentrations of Shin & Paik's Method were Significantly higher than those of the NIOSH/EPA Method or the OSHA method. We concluded that the Shin & Paik's Method could prevent Cr(VI) losses caused by reduction and give more reliable results of airborne Cr(VI) concentrations in work environments.
Hong, Ji Hyun;Lee, Jae Myung;Kang, Min Jong;Kim, Dong Gyu;Jung, Ki-Suck;Jang, Kee-Tark;Park, Hye-Rim;Lee, In Jae
Tuberculosis and Respiratory Diseases
/
v.52
no.4
/
pp.419-424
/
2002
A 44 year old man was admitted complaining fo exertional dyspnea. The patient denied any occupational history of hard metal exposure. Chest radiography showed an increased interstitial marking at the peripheral portion of both lower lung fields. The spirometric values were within the normal ranges. However, the diffusion capacity of the lungs was lower. In the bronchial lavage fluid, the characteristic multinucleated giant cells were noticed, and the macrophage compartment was 96% and the neutrophils were 4%. High-resolution CT scan revealed ground glass opacities with emphysematous lung changes at the peripheral portion of the whole lung. An open lung biopsy confirmed the presence of numerous multinucleated giant cells (define GIP) with an associated interstitial fibrosis throughout the lung. The radiographic abnormailities and symptoms subsequently improved following treatment with oral corticosteroids.
This study aimed to investigate the influence of shoe heel height and muscle fatigue on static and dynamic balance in young women. Thirty women who were used to wearing high heels volunteered to participate in this study. The shoe heel heights were 0 cm and 7 cm. And ankle plantar flexor fatigue was experimentally induced. Static and dynamic balance were measured using the one leg standing test (OLST) and the star excursion balance test (SEBT) in anterior, posteromedial, and posterolateral directions, respectively. Values in the OLST (shoe heel height 0 cm, $28.83{\pm}3.24$ sec to $26.12{\pm}6.13$ sec; and 7 cm, $24.75{\pm}7.09$ sec to $16.86{\pm}9.32$ sec) and the SEBT in anterior (shoe heel height 0 cm, $71.02{\pm}4.57%$ to $69.50{\pm}3.66%$; and 7 cm, $64.17{\pm}3.53%$ to $59.61{\pm}4.06%$) and posteromedial (shoe heel height 0 cm, $92.01{\pm}5.61%$ to $90.38{\pm}7.10%$; and 7 cm, $83.09{\pm}7.29%$ to $76.83{\pm}9.28%$) directions were significantly reduced when fatigue-inducing exercise was performed (p<.05). Furthermore, within these parameters, there were significant interaction effects between shoe heel height and fatigue condition (p<.05). These findings suggest that shoe heel height and muscle fatigue contribute to some changes in static and dynamic balance in young women, probably leading to negative effects on physical function during a variety of activities of daily living.
Kim, Eunhye;Moon, Joon-Kwan;Lee, Hyeri;Kim, Suhee;Hwang, Yon-Jin;Kim, Byung-Joon;Lee, Jinbeum;Lee, Dong-Hyuk;Kim, Jeong-Han
Horticultural Science & Technology
/
v.31
no.2
/
pp.239-245
/
2013
Occupational exposure and risk assessment were conducted to evaluate the safety of operators when insecticide acetamiprid was applied to apple orchard using a speed sprayer. Dermal patches, cotton gloves, socks, and masks were used to monitor the dermal exposure, and personal air pump with solid sorbent was used to measure the potential inhalation exposure. In validation to analytical methods, the limit of detection and limit of quantitation were 0.25 ng and 1 ng, respectively. Good reproducibility (coefficient variation < 4%), linearity (coefficient determination > 0.999), and recovery (85.3-118.2%) were obtained. Trapping efficiency of solid sorbent was 96.4% while breakthrough did not occur. Only hand exposure was measured on the gloves during mixing/loading to give $33-1,132{\mu}g$. Exposure amount of operator 3 among 4 workers was noticeably high. The total volumes of spray liquid for operators were $535-1,235mL{\cdot}h^{-1}$, corresponding to 0.03-0.08% of the applied spray solution. Highest contaminated parts of body were thighs, chest, and lower legs. The inhalation exposure ratio to the total application amount was significantly low. However, wind seemed to affect the inhalation exposure of operator. For risk assessment, margin of safety was calculated by the application of cloth and dermal penetration rate to obtain values of much larger than 1 in all cases. Therefore, health risk of operators during treatment of acetamiprid in apple orchard could be of least possibility.
Journal of Korean Society of Occupational and Environmental Hygiene
/
v.1
no.2
/
pp.221-237
/
1991
This study was conducted to evaluate the accuracy and the precision of asbestos counting data produced by the Division of Industrial Health, School of Public Health, Seoul National Universitys (SNU). The study was performed from July 18 to October 4, 1991, and the results are summarized as follows. 1. Intracounter Relative Standard Deviations (Sr) in the category of 5-50.5 fibers as total fibers counted ranged from 0.27 to 0.37, which were greater than 0.10-0.17 which were reported by the NIOSH. The reasons are supposed to be as follows. First, inexperience of counters in asbestos fiber counting was considered to be a main reason. Second, poor quality of samples due to sampling and mounting error increased variation of counting. Third, fiber density of many samples were less than $100fibers/mm^2$. But Intracounter Relative Standard Deviations (Sr) in samples with >50.5 fibers ranged from 0.l6 to 0.20, approaching the value 01 NIOSH. 2. Intralaboratory Relative Standard Deviations (Sr) in categories of 5-20.5, >20.5-50.5 and >50.5 fibers were 0.54, 0.37 and 0.26, respectively. Intralaboratory Sr in samples with fiber density greater than $100fibers/mm^2$ was 0.26. This was similar to the values reported by other foreign experienced laboratories. 3. Comparing results of three counters, Counter C, a beginner, overestimated asbestos fiber concentrations. 4. Since our SNU laboratory has participated in two quality control programs, IOMA-F.R.I.C.A., U.K. and NIOSH PAT Program, U.S.A., this laboratory has been evaluated as " Rating 1" and "Proficient" laboratory, by IOM and NIOSH, respectively.
Journal of Korean Society of Occupational and Environmental Hygiene
/
v.3
no.2
/
pp.227-239
/
1993
The author selected 77 dust emissing processes from 71 types of industries which placed in Sasang Industrial Complex in Pusan. The level of total dust was measured as areal concentration and personal exposure concentration by low volume air sampler and personal air sampler, respectively. Collected samples were classified into 5 groups (chemicals and rubber product, metal product, sawmills and wood, foundries and others). Respirable particulate and total dust of areal and personal exposure were analyzed. The results were as follows; 1. All of the respirable dust concentration and total dust of areal and personal concentration were log-normally distributed. 2. Geometric mean of respirable particulate of personal exposure concentration measured $0.55mg/m^3$ in the first group, $0.86mg/m^3$ in the second group, $0.39mg/m^3$ in the third group, $0.81mg/m^3$ in the forth group and $0.52mg/m^3$ in the fifith group. The exceed rates over TLV (thehold limit values) of total dust were 31.3% in the first group, 31.3% in the second group, 70% in the third group, 80% in the forth group and 13.3% in the fifth group. 3. There were singnificant difference between areal and personal exposure concentration and personal exposure concentration was higher than that of area. 4. In the case of high ratio of respirable particulate to total dust, pneumoconiosis incidence was high even though the workshop was opened and emissing dust concentration was low. These findings suggest that it is desirable to measure respirable particulate in environmental assessment of dust emissing workshops.
The purpose of this study was to serve as a basis for the development of dental technology and for creating a condition that dental technicians could work with pride and right values, by examining what problems there were in their health care, what they thought about them, and how the problems could be solved, The findings of this study were as below: 1. The most serious and harmful element in dental technology workshop was a dust(57.5%) and a noise(33.3%). 2. Approximately 99.0% of the dental technicians investigated made a complain of air pollution caused by noise. Their opinion on a possible measure to remove noise air pollution was that the noise-generating machine should be replaced(64.1%) or that it should be isolated(28.8%). 3. 76.0% complained air pollution cause by dust deteriorates their working efficiency. As a way to eliminate it, they suggested a dust chamber(35.3%) or an air cleaner(27.5%) should be installde. 4. About 80% made a complain of gas air pollution. The most common related symptom was a headache(56.9%). They thought that gas-generating machine should be isolated(39.9%) or that an air purifier should be prepared(33.3%). 5. The largest impact of heat and light on their body was weakening their eyesight(56.9%). 47.1% got burn once though four times, and 34.3% did five times or more. The way to prevent them was to install an automatic casting machine(66.0%) or use protective glasses(28.1%). 6. Approximately 47.7% were considering a change of occupation, and the most common reason was heavy work(23.5%), followed by poor prospect(21.6%) and working environment(19.0%) in the order named. 7. 88.9% responded they were likely to have an occupational disease. Their idea about the proper frequency of regular health examination was once a year(53.6%), or once per every six months(41.8%). 8. The field they were most interested in was health care(39.2%), followed by academic research activities(31.4%). This fact indicated it's most urgently required to improve their working environment.
The purpose of this study was to evaluate a new sampling and analytical method for the determination of airborne hexavalent chromium, Cr(Ⅵ), in a field plating operation. The procedures of this new method (Shin & Paik's Method) are as the following: Airborne hexavalent chromium is collected on polyvinyl chloride (PVC) filter according to the National Institute iota Occupational Safety and Health (NIOSH) Method 7600, and the filler sample is placed in a screw-capped vial and soaked with 2% NaOH/3% Na₂CO₃ solution immediately after sampling. The Cr(Ⅵ) sample is analyzed by ion chromatography/visible spectrophotometry (IC/VS) according to the U.S. Environmental Protection Agency (EPA) Method 218.6. The airborne Cr(Ⅵ) concentrations measured by this method were compared with those determined by three reference methods: One (NIOSH/EPA Method) consisted of sampling airborne Cr(Ⅵ) on PVC filters and storing the sample filters in strew-capped vials according to the NIOSH method, and analyzing Cr(Ⅵ) in samples using IC/VS according to the EPA method. The second method (Impinger Method/NaHCO₃) consisted of absorbing airborne Cr(Ⅵ) into 0.02 M NaHCO₃ solution in midget impinger, and analyzing the Cr(Ⅵ) in samples using IC/VS. The third method was the OSHA Method ID-215. Using these four different methods, lour replicates of air samples were collected at an electroplating process and analyzed simultaneously. Two-way ANOVA and paired t-test were used to test difference among values determined by the methods. There was no significant difference and a strong correlation (r²:0.99) between Cr(Ⅵ) concentrations measured by the Shin & Paik's Method and an impinger method (p>0.05). However, Cr(Ⅵ) concentrations determined by Shin & Paik's Method were significant1y different from those by the NIOSH/EPA Method (p<0.05) or the OSHA method (p<0.05). The Cr(Ⅵ) concentrations of Shin & Paik's Method were significantly higher than those of the NIOSH/EPA Method or the OSHA method. This result indicated that the Shin & Paik's Method may prevent Cr(Ⅵ) losses caused by reduction and give more reliable results of airborne Cr(Ⅵ) concentrations in work environments.
Acetaminophen (paracetamol), generally used as a pain reducing agent, has good analgesic efficacy in toothaches and headaches, but is of little use in inflammatory and visceral pain. This study was performed to analyze the level of acetaminophen in the Kyongahn river and to investigate the ecological risks of target compounds. Sampling sites were Haesil, Soopyo, Wangsan, Kyongahn, Jiwol, Kwangdong, Paldang and they were analyzed in June and August, 2005. Acute toxicity of acetaminophen wwas evaluated for Daphnia magna. From the ecotoxicological results, environmental risk assessments were performed for acetaminophen residues in Kyongahn river to predict their potential adverse effect. Acetaminophen was detected at Kyonahn river, $0.439{\mu}g/l$). The toxic concentration of acetaminophen calculated with 48-h $LC_{50}$ values as 16.9 mg/l. These results indicated that acetaminophen had no significant ecotoxicological impact on short-term acute exposure.
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