• The Korean Journal of Pain
• /
• 제33권1호
• /
• pp.73-80
• /
• 2020

Background: The aim of this study was to evaluate radiation exposure to the eye and thyroid in pain physicians during the fluoroscopy-guided cervical epidural block (CEB). Methods: Two pain physicians (a fellow and a professor) who regularly performed C-arm fluoroscopy-guided CEBs were included. Seven dosimeters were used to measure radiation exposure, five of which were placed on the physician (forehead, inside and outside of the thyroid protector, and inside and outside of the lead apron) and two were used as controls. Patient age, sex, height, and weight were noted, as were radiation exposure time, absorbed radiation dose, and distance from the X-ray field center to the physician. Results: One hundred CEB procedures using C-arm fluoroscopy were performed on comparable patients. Only the distance from the X-ray field center to the physician was significantly different between the two physicians (fellow: 37.5 ± 2.1 cm, professor: 41.2 ± 3.6 cm, P = 0.03). The use of lead-based protection effectively decreased the absorbed radiation dose by up to 35%. Conclusions: Although there was no difference in radiation exposure between the professor and the fellow, there was a difference in the distance from the X-ray field during the CEBs. Further, radiation exposure can be minimized if proper protection (thyroid protector, leaded apron, and eyewear) is used, even if the distance between the X-ray beam and the pain physician is small. Damage from frequent, low-dose radiation exposure is not yet fully understood. Therefore, safety measures, including lead-based protection, should always be enforced.

• Nuclear Engineering and Technology
• /
• 제13권3호
• /
• pp.161-167
• /
• 1981

자주달개비(Tradescantia) BNL clone 4430을 본 연구소 감마농장(${\gamma}$-field)에 거리별로 배치하고 ${\gamma}$-선을 3.6mR/day~182R/day의 선량율로 완조사시켜, 이 식물의 수술털에 나타나는 분홍색 체세포돌연변이를 대상으로 돌연변이의 출현율을 조사하는 한편 화기에 미치는 형태변화를 조사하였다. 분홍색 체세포돌연변이율은 22.2R/day의 선량율에서 수술털 1,000개당 85.81$\pm$6.45개로 가장 높았고, 이보다 높은 선량율에서는 오히려 변이율이 감소하여 포화선량효과를 초래하였다. 또한 3.6mR/day의 낮은 선량율체서도 이 체세포돌연변이율이 자연돌연변이율보다 증가하였음을 볼 수 있었으며 비교적 낮은 선량율 조사에서는 꽃, 수술, 수술털등의 형태적 변화가 없이 돌연 변이율만의 증가를 볼수가 있어 감마농장내에서 과수나 화목등 영년식물에 저선량의 완조사를 통해 체세포돌연변이의 유기가 가능할것으로 보이며, 한편 이 식물의 특성을 이용하여 저위 방사선에 의한 유전적변화를 탐지하는데에도 적절한 수단이 될 것 같다.

• Toxicological Research
• /
• 제33권4호
• /
• pp.305-313
• /
• 2017

Accumulating epidemiological evidence indicates that exposure to fine air pollution particles (APPs) is associated with a variety of adverse health effects. However, the exact physiochemical properties and biological toxicities of fine APPs are still not well characterized. We collected four types of fine particle (FP) (diesel exhaust particles [DEPs], natural organic combustion [NOC] ash, synthetic organic combustion [SOC] ash, and yellow sand dust [YSD]) and investigated their physicochemical properties and in vitro biological toxicity. DEPs were almost entirely composed of ultrafine particles (UFPs), while the NOC, SOC, and YSD particles were a mixture of UFPs and FPs. The main elements in the DEPs, NOC ash, SOC ash, and YSD were black carbon, silicon, black carbon, and silicon, respectively. DEPs exhibited dose-dependent mutagenicity even at a low dose in Salmonella typhimurium TA 98 and 100 strains in an Ames test for genotoxicity. However, NOC, SOC, and YSD particles did not show any mutagenicity at high doses. The neutral red uptake assay to test cell viability revealed that DEPs showed dose-dependent potent cytotoxicity even at a low concentration. The toxicity of DEPs was relatively higher than that of NOC, SOC, and YSD particles. Therefore, these results indicate that among the four FPs, DEPs showed the highest in vitro biological toxicity. Additional comprehensive research studies such as chemical analysis and in vivo acute and chronic inhalation toxicity tests are necessary to determine and clarify the effects of this air contaminant on human health.

• 한국수산과학회지
• /
• 제35권5호
• /
• pp.534-541
• /
• 2002

살충제, 살균제 그리고 antifouling 약품 등으로써의 triorganotin의 사용은 지난 30년간 놀라울 정도로 증가해왔다. 이 보고에서는 미세조류 Skeletonema costatum의 성장에 미치는 여러 triorganotin (TBTO, TBTF, CTPT, TBTCI)들의 급성 및 만성 독성효과를 조사하기 위하여, 단기 및 장기 독성실험을 각각 수행하였다. 단기 독성실험에서, 여러 triorganotin들의 S. costatum에 대한 성장저해 효과는 처리농도에 비례하여 증가하였으며, 이 성장저해는 시간 경과에 따라 회복되었다. 그러나 여러 triorganotin의 독성의 성장저해 효과가 접종한 S. costatum의 세포밀도에 따라 다름을 보였다. 접종 세포농도가 높을수록 triorganotin의 독성효과는 감소하였다. 이러한 결과는 triorganotin의 S. costatum에 의한 분해에 의한 것이라고 판단된다. 장기 독성실험에서는 단기 독성실험에서와는 달리 1 $\mu$g/L의 triorganotin의 농도에서도 S. costatum이 사멸하였다. 이러한 사실은 낮은 밀도의 식물성 플랑크톤이 존재하는 해수에서 지속적으로 존재하는 triorganotin의 독성은 훨씬 더 강하게 나타날 수 있음을 보여준다.

• Journal of Preventive Medicine and Public Health
• /
• 제27권3호
• /
• pp.487-504
• /
• 1994

A cross-sectional study was performed to evaluate the effects of chronic low-dose solvent on neurobehavioral performance of 118 male car painters. A control group of 113 workers matched for age was selected from different sections of the factory. The mean age and the mean duration of employment were 33 years and 6.7 years in both groups. Mean years of education were 11.4 years in car painters and 11.8 years in controls. Each worker completed a medical and occupational questionnaire and four tests of Swedish performance evaluation system. These included simple reaction time, symbol digit, digit span and finger tapping speed. Althougth the mean duration of employment was 6.7 years, comparison of mean performance showed a significantly poorer performance on simple reaction time (p<0.05), symbol digit(p<0.01) and digit span(p<0.05) in car painters. In univariate analysis, age and educational level contributed to poorer performance on symbol digit and digit span. Smoking appeared to slow finger tapping speed in car painters. Performance of four tests of car painters exposed to high level of solvent was poorer than that of car painters exposed to low level. In multiple regression models, controlling for age, alcohol, smoking and shift work, solvent exposure was found to be associated with performance of simple reaction time, symbol digit and digit span and exposure to high level of solvent was related to poorer performance of symbol digit and digit span.

• 한국환경과학회지
• /
• 제19권4호
• /
• pp.527-532
• /
• 2010

Exposure to lead, particularly at chronic low-dose levels, is still a major public health concern. The present study is aimed to evaluate the blood lead levels in populations resident in some abandoned mine areas of Chungbuk, Korea. Eight hundreds and sixty-six subjects who reside in abandoned mine area located in Chungbuk, Korea, were enrolled this study. We evaluated the blood lead level according to the age, gender, and working history in mines. For statistical analysis, SPSS ver 12.0 was used. The geometric mean blood lead levels was $2.93\;{\mu}g/{\ell}$ and nobody showed levels over the guidelines of WHO. Ex-smokers and current-smokers showed significantly higher blood lead levels compared to that of non-smokers. The blood lead levels in individuals with a history of working in a mine was higher than those in individuals without such histories. The populations resident in some Chungbuk abadoned mine area showed low levels of lead in blood. This suggest that lead poisoning might not be induced by abandoned mine in Chungbuk, Korea.

• Toxicological Research
• /
• 제18권1호
• /
• pp.23-29
• /
• 2002

Disodium disulphite, the HPV chemical, was assigned to Korea in order to implement OECD SIDS program in 1999. It was produced about 3,200 ton/year in 1998. This report evaluates the toxic potency of disodium disulphite based on the environmental and mammalian effects as well as human exposure. Oral $LD_{50}$ in rats is 1,540 mg/kg b.w. and effects was observed to the stomach, liver and the GI track that was filled with blood. For repeated dose toxicity, the predominant effect was the induction of stomach lesion due to local irritation. The no observed adverse effect lever for local (stomach irritation) was about 217 mg/kg bw/day. There is no evidence that disodium disulphite is genotoxic in vivo. No reproductive or developmental toxicty of disodium disulphite was observed for the period up to 2 yr and over three generation. In humans, urticaria and asthma with itching, edema, rhinitis, and nasal congestion were reported. Disodium disulphite is unlikely to induce respiratory sensitization but may enhance symptom of asthma in sensitive individuals. This chemical would be mainly transported to water compartment when released to environmental compartments since it is highly water soluble (470 g/l at 20). Low K oc (2.447) indicates disodium disulphite is so mobile in soil that it may not stay in the terrestrial compartment. The chemical has been tested in a limited number of aquatic species. hem acute toxicity test to fish, 96 hr-$LC_{50}$ was > 100 mg/1. For algae, 72 hr-$XC_{50}$ was 48.1 mg/1. For daphnid, the acute toxicity value of 48 hr-$EC_{50}$ was 88.76 mg/1, and chronic value of 21day-NOEC was > 10 mg/1. Therefore, PNEC of 0.1 mg/l for the aquatic organism was obtained from the chronic value of daphnid using the assessment factor of 100. Based on these data the disodium disulphite was recommended as low priority for further post-SIDS work in OECD.

• Environmental Analysis Health and Toxicology
• /
• 제25권2호
• /
• pp.161-168
• /
• 2010

The observed the toxic effect of WSF (Water Soluble Fraction) on development time, development rate, attachment rate, survival rate and growth of the larva during the early stage of the Pacific oyster, Crassostrea gigas. The time required early juvenile from the fertilized eggs exposed to crude oil (WSF) was about 13 hours in control group. But that of the crude oil dose group takes 12 hours, with shorter compared to control group. Development and attachment rate of the oyster significantly higher in 0.4 and 0.8 mg/L WSF compared to control group (P<0.05) but significantly lower more than 1.6 mg/L WSF (P<0.05). Survival rate of the oyster larva significantly higher in 0.4 and 0.8 mg/L WSF compared to control group (P<0.05) but significantly lower more than 2.4 mg/L WSF (P<0.05). Survival rate of spot showed no significantly difference compared to control group (P>0.05). Shell growth of the oyster were significantly lower more than 1.6 mg/L WSF compared control group (P<0.05). The effect concentration of crude oil showed that more 0.4 mg/L in development and attachment rate and more 1.6 mg/L in growth. Also, chronic exposure of crude oil even effect also in low concentration.

• 한국발생생물학회지:발생과생식
• /
• 제27권4호
• /
• pp.213-220
• /
• 2023

Previously, we showed that a chronic-low-dose nonylphenol (NP) exposure resulted in histological changes with sexually dimorphic pattern in rat adrenal glands. We hypothesized that such structural changes are closely related to the hormonal secretory patterns. To test this hypothesis, we developed the short-term adrenal incubation method, and measured the levels of catecholamines and cortical steroids using the high-performance liquid chromatography with electrochemical detection (HPLC-ECD) and specific enzyme-linked immunosorbent assay, respectively. The norepinephrine (NE) levels in media from NP-treated female adrenal, except 100 pM NP, were significantly increased [control (CTL) vs 1 nM NP, p<0.001; vs 10 nM NP, p<0.05; vs 100 nM NP, p<0.001; vs 1 µM NP, p<0.01]. The NE secretion from male adrenal was higher when treated with 100 nM and 1 µM NP (CTL vs 100 nM NP, p<0.05; vs 1 µM NP, p<0.05, respectively). The aldosterone level in the female adrenal media treated with 100 pM NP was significantly decreased, on the other hand, that of media treated with 10 nM NP was significantly increased (CTL vs 100 pM NP, p<0.05; vs 10 nM NP, p<0.01). In male adrenal media, the aldosterone levels of 10 nM, 100 nM and 1 µM NP-treated media were significantly declined (CTL vs 10 nM NP, p<0.001; vs 100 nM NP, p<0.001; vs 1 µM NP, p<0.001). These results showed the NP treatment altered secretory pattern of aldosterone from adrenals of both sexes, showing sexual dimorphism. It may be helpful for understanding possible adrenal pathophysiology, and endocrine disrupting chemicals-related sexually dimorphic phenomena in adrenals.

• Journal of Preventive Medicine and Public Health
• /
• 제31권3호
• /
• pp.424-439
• /
• 1998

1995년 8월부터 12월 사이에 미량의 카드뮴에 오염된 것으로 밝혀진 폐광 인근 지역에 거주하고 있는 지역주민 184명(남자: 82명, 여자: 102명)을 대상으로 카드뮴에 의한 만성적인 폭로와 신기능장애를 평가하기 위하여 요중 카드뮴과 NAG활성도, $\beta_2MG$배설량 및 총단백질량을 정량하여 비교 분석하였다. 이때 특별히 카드뮴에 폭로된 적이 없는 일반주민 160명(남자 : 64명, 여자 : 96명)을 대조군으로 선정하였다. 남자의 경우 폭로군의 요중 평균 카드뮴농도는 $2.56{\mu}g/\ell,\;2.80{\mu}g/g$ creatinine 및 $2.50{\mu}g/S.G.$, 대조군은 $1.19{\mu}g/\ell,\;1.36{\mu}g/g$ creatinine 및 $1.17{\mu}g/S.G.$ 였고, 여자에서는 폭로군 $2.69{\mu}g/\ell,\;3.94{\mu}g/g$ creatinine 및 $2.63{\mu}g/S.G.$, 대조군 $1.27{\mu}g/\ell,\;1.97{\mu}g/g$ creatinine 및 $1.25{\mu}g/S.G.$로서 폭로군이 대조군에 비해 남 여 모두에서 유의하게 높았다. 연령에 따른 요중 평균 카드뮴 농도는 남자의 경우 $20\sim39$세군에서는 폭로군과 대조군간에 차이가 없었으나, $40\sim59$세군과 60세 이상군에서는 폭로군이 유의하게 높았다. 여자에서는 폭로군이 대조군에 비해 모든 연령층에서 유의하게 높았다. 또한, 폭로군에 있어서 조사대상 지역에 거주한 기간이 길수록 그리고 이 지역에서 생산된 쌀과 채소류를 섭취하는 사람들의 요중 카드뮴 농도가 높게 나타나, 폐광 인근 지역주민들이 미량이지만 상대적으로 많은 양의 카드뮴에 만성적으로 폭로되고 있는 것으로 추정되었다. 폭로군과 대조군의 요중 평균 NAG활성도, $\beta_2-MG$ 배설량 및 총단백질량은 두 군간에 유의한 차이가 없었다. 그러나, 폭로군에서 요중 NAG활성도와 총단백질량은 요중 카드뮴량과 통계적으로 유의한 정상관이 있었으나 $\beta_2-MG$ 배설량은 유의하지 않았다. 또한 2.0 미만군, 2.0이상 10.0미만군, 10.0이상군으로 구분한 요중 카드뮴 농도수준에 따른 분석시 요중 카드뮴 2.0미만군에 비해 10.0이상군의 NAG활성도, $\beta_2-MG$배설량 및 총단백량이 유의하게 증가되었으며, NAG활성도는 2.0이상 10.0미만군에서도 유의하게 증가되었다. 즉, 폭로군에서 요중 카드뮴 농도에 따른 요중 NAG활성도의 증가가 $\beta_2-MG$배설량의 증가에 비해 상대적으로 민감하게 나타나, 향후 카드뮴 폭로군에 대한 색출검사시 $\beta_2-MG$배설량과 함께 NAG활성도를 조사함으로써 조기진단적 가치가 높을 것으로 사료된다.