나노 독성의 개념 및 나노입자에 대한 위해성 평가의 필요성

맹승희(Seung Hee Maeng),유일재(Il Je Yu) 한국독성학회 2005 Toxicological Research Vol.21 No.2

Human exposure to nano-sized particles (NSP) has increased over the last century with anthropogenic sources, and the rapid development of nanotechnology becomes an another source of such exposure. Information regarding the safety of nanotechnology and its product, nanoparticles, is urgently needed when assuming exposure through inhalation, oral intake, and penetration across skin is ever increasing as growing nanotechnology rapidly. The recent advancement of biokinetic studies with NSP and newer epidemiologic and toxicologic studies with ultrafine particles can be the basis for the nanotoxicology. Some concepts of nanotoxicology can be known from the results of these results. Specific small size of NSP, when inhaled, facilitates deposition by diffusional mechanism in all regions of the respiratory tract and uptake into cells, transcytosis across epithelial and endothelial cells into the blood and lymph circulation to reach target sites. Translocation along axons and dendrites of neuron makes an access to CNS and ganglia. These biokinetics are dependent on NSP surface chemistry. Risk assessments of NSP include appropriate and relevant doses/concentration selections, the increase effects in the organism and the benefits of possible desirable effects. An interdisciplinary team approach is desirable for nanotoxicology research and an appropriate risk assessment.

Benzidine dihydrochloride에 의한Chinese hamster lung 세포의 적응반응

맹승희(Seung Hee Maeng),정해원(Hai Won Chung),이권섭(Kwon Seob Lee),이용묵(Yong Mook Lee),정호근(Ho Keun Chung),유일재(Il Je Yu) 한국환경성돌연변이발암원학회 2001 한국환경성돌연변이·발암원학회지 Vol.21 No.2

We studied adaptive response in CHL cells by benzidine dihydrochloride, a derivative of benzidine, which was a major mutagenic agent in dye industry. Chromosome aberration analysis was used for the identification of adaptive response to this mutagen. Adaptive and reactive doses were confirmed by cell proliferation<br/> rate curve. Cell proliferation rate curve was obtained from the mitotic indices of cells treated with various concentrations of benzidine dihydrochloride for 24 hours. Marked adaptive responses to benzidine dihydrochloride in the induction of chromosome aberration were observed in CHL cells by pre-treatment with low concentrations of benzidine dihydrochloride (0.0047 mg/ml or 0.0094 mg/ml) for 24 hours following post-treatment with high concentrations (0.0187, 0.0375, 0.075, 0.15 mg/ml) for 24 hours. These adaptive responses were found mostly in the type of chromatid breaks and chromatid exchanges. There is no difference in these results between two adaptive doses, 0.0047 mg/ml and 0.0094 mg/ml. The amount of adaptive response, however, was dependent on post-treatment doses.

흰주의 6가 크롬 흡입폭로에 의한 산화적 손상에 관한 연구

맹승희(Seung Hee Maeng),유일재(Il Je Yu),김현영(Hyeon Yeong Kim),임철홍(Cheol Hong Lim),이용묵(Yong Mook Lee),정호근(Ho Keun Chung),정해원(Hai Won Chung) 한국환경성돌연변이발암원학회 2002 한국환경성돌연변이·발암원학회지 Vol.22 No.4

According to the epidemiological studies in chromium workers, hexavalent chromium is associated with the risk of lung cancer. Cellular oxidative damages by reactive oxygen species produced by hexavalent chromium exposure may play an important role in the carcinogenesis process. We investigated the availabilities of malondialdehyde measurement for the assessments of oxidative damages from chromium exposure with an experimental inhalation study in vivo. Lipid peroxidation, one kind of cellular oxidative damage, was measured in blood plasma of the rats which inhaled the hexavalent chromium mist for 1, 2 and 3 weeks. The concentrations<br/> of malondialdehyde (MDA), the metabolite of lipid peroxidation, in all exposed groups were higher than those of controls with dose-dependant manner. The levels of MDA were also correlated with urine chromium levels of the rats. Therefore, MDA as an indicator of lipid peroxidation could be proper biologic marker for the<br/> assessment of the oxidative damage from chromium exposure, which might be involved in carcinogenesis.

Ames test 결과와 QSAR를 이용한 변이원성예측치와의 비교

양숙영(Sook Young Yang),맹승희(Seung Hee Maeng),이종윤(Jong Yun Lee),이용묵(Yang Mook Lee),정호근(Ho Keun Chung),정해원(Hai Won Chung),유일재(Il Je Yu) 한국환경성돌연변이발암원학회 2000 한국환경성돌연변이·발암원학회지 Vol.20 No.1

Recently there is increasing interest in the use of structure activity relationships for predicting the biological activity of chemicals. The reasons for the interest include the decrease cost and time per chemical as compared with animal or cell system for identifying toxicological effects of chemicals and the reduction in the use of animals for toxicological testing. This study is to test the validity of the mutagenicity data generated from QSAR (Quantitative Structure Activity Relationship) program. Thirty chemicals, which had been evaluated by Ames test during 1997-1999, were assessed with TOPKAT QSAR mutagenicity prediction module. Among 30 chemicals experimented, 28 were negative and 2 were positive for Ames test. On the contrary, 23 chemicals showed the high confidence level indicating high prediction rate in mutagenicity evaluation, and 7 chemicals showed the low to moderate confidence level indicating low prediction in mutagenicity evaluation. Overall mutagenicity prediction rate was 77% (23/30). The prediction rates for non-mutagenic chemicals were 79% (22/28) and mutagenic chemicals were 50% (1/2). QSAR could be a useful tool in providing toxicological data for newly introduced chemicals or in furnishing data for MSDS or in determining the dose in toxicity testing for chemicals with no known toxicological data.

Sprague-Dawley 랫드에서 60일간 용접흄 폭로에 의한 폐기능 변화

성재혁(Jae Hyuk Sung),최병길(Byung-Gil Choi),맹승희(Seung-Hee Maeng),김수진(Soo-Jin Kim),정용현(Young Hyun Chung),한정희(Jeong Hee Han),현진숙(Jin Suk Hyun),송경석(Kyung Seuk Song),조영봉(Yong Bong Cho),조명행(Myung-Haing Cho),유일재 한국독성학회 2004 Toxicological Research Vol.20 No.1

Respiratory effects in full time welders include bronchitis, airway irritation, lung function changes, and lung fibrosis. Welder's pneumoconiosis has been generally determined to be benign<br/> and not associated with respiratory symptoms based on the absence of pulmonary function abnormalities in welders with marked radiographic abnormalities. Accordingly, to investigate pulmonary function changes during 60 days induced by welding-fume exposure, male Sprague-Dawley rats were exposed to manual metal arc-stainless steel (MMA-SS) welding fumes with concentrations of 64.8+0.9 mg/㎥ (low dose) and 107.8±2.6 mg/m3 (high dose) total suspended particulates for 2 hr/day, 5 days/week in an inhalation chamber for 60 days. Pulmonary function was measured every week with whole body plethysmograph compensated (WBP Comp, SFT38116, Buxco Electronics, Sharon, CT). The rats exposed to the high dose of welding fumes exhibited statistically significant (p<0.05-0.01) body weight decrease as compared to the control whereas cell number increase of the bronchoalveolar lavage fluid (BALF) (total cell, macrophage, polymorphonuclear cell and lymphocyte) during the 60 days exposure period. And only tidal volume was significantly decreased in dosedependantly during 60 days of MMA-SS welding fume exposure. This pulmonary function change with inflammatory cell recruitment confirms the lung injury caused by the MMA-SS welding fume exposure.

용접흄 흡입노출 영장류에서 Fpg/Endo 3 FLARE Assay를 이용한 DNA 손상 및 회복

임경택 ( Kyung Taek Rim ),김수진 ( Soo Jin Kim ),정용현 ( Yong Hyun Chung ),김현영 ( Hyeon Yeong Kim ),맹승희 ( Seung Hee Maeng ),유일재 ( Il Je Yu ) 한국산업위생학회 2007 한국산업보건학회지 Vol.17 No.4

근로자 일반 검진과 개인별 종합검진의 일치도

유선미,임민경,고경실,맹승희 대한보건협회 1998 대한보건연구 Vol.24 No.1

산업안전보건법에 근거하여 시행되는 근로자 일반건강진단은 근로자에게 정기적인 건강진단을 실시하여 근로자의 건강을 유지·증진시키기 위한 2차 예방사업이다. 본 연구에서는 일반건강진단의 효과를 평가하기 위하여 검진의 표적 질환 및 검사항목 선정, 검진실시 과정, 검진결과 및 사후관리 체계에 대하여 표적 질환 및 검사항목 선정에 대한 평가에 주목하여 검토하였다. 1996년 충남 소재 반도체 생산업체 생산직 근로자 581명을 대상으로 근로자 일반건강진단과 개인별 종합검진을 시행하고 건강진단 결과와 의무기록상의 의사의 진단을 조사하여 다음과 같은 결과를 얻었다. 1. 일반건강진단의 표적질환군 중에서 한국인의 10대 사인, 공무원 및 사립학교 교직원 의료보험상병자료에서 유병률이 높은 질환에 속하는 것은 호흡기 결핵, 간장질환, 당뇨, 고혈압 등이었다. 2. 일반건강진단은 개인별 종합겁진에 비해 검사 항목이 더 적고, 검진에 소요되는 시간이 길고, 의사의 개별적인 상담을 받을 기회가 적었다. 집단을 대상으로 시행하는 일반건강진단의 사후관리는 2차 검진 결과를 통보하고 난 뒤에는 개인에게 일임하고 있었다. 3. 일반건강진단 결과 유소견자(C)와 일반 질환자(D2) 중에는 소화기 질환이 가장 많았고, 순환기, 호흡기, 비뇨생식기 질환, 호흡기 결핵 순이었으며, 고혈압과 호흡기 결핵을 제외하면 구체적인 진단을 얻을 수 없었다. 개인별 중합검진의 경우 일반검진을 이용해서 얻지 못하면서 임상적으로 중요한 진단으로 십이지장궤양, 위궤양, 위암, 간경변, 폐암, 협심증, 요로감염, 신장암 등이 있었다. 일반건강진단과 종합검진에서 진단이 일치한 경우는 전체의 53.9%였고, kappa index는 0.249(p=0.000)였다. 일반건강진단 결과 가장 많았던 소화기 질환은 개인별 종합검진에서는 지방간, 정상, 간염 건강보균자, 간기능 이상, 알코올성 간염 등으로 구체적인 진단을 받았다 4. 1차 검진 이상자(절차구분 R)에게 시행한 2차 검진은 고지혈증의 경우 검사 이상을 보이는 경우가 많았으나, 간장 질환, 비뇨생식기 질환의 경우는 최종 진단을 결정하는데 크게 기여하지 않았다. 효과적인 일반건강진단을 통해 근로자의 건강증진을 도모하기 위하여 검진의 목표, 표적질환, 검사항목, 검진실시 과정, 결과 추구 관리에 대한 체계적인 연구가 필요하다. Workers' periodic health examination is secondary level preventive service which aims health promotion at work site. This study concerns the target diseases, clinical tests, the result, and the follow-up strategies to explore the effect of periodic health examination. 581 workers in semiconductor-manufacturing factory were selected for this study in 1996. We analysed the result of examination and diagnosis by doctors in hospital medical records. The result is as follows, 1. Target diseases of workers' periodic health examination which belong to 10th common causes of death in Korea and rank as common diseases in medical insurance prevalence were respiratory tuberculosis, liver diseases, diabetes mellitus, and hypertension. 2. The most common findings which showed abnormal result was disease of digestive system, followed by diseases of circulatory, respiratory, urogenital system and respiratory tuberculosis. But the diagnosis by periodic health examination was not concrete except hypertension and tuberculosis, and didn't cover important diagnoses such as peptic ulcer disease, gastric cancer, liver cirrhosis, angina pectoris, urinary tract infection and kidney cancer. 3. Most results of confirmatory health examination to make an valid diagnosis about hyperlipidemia revealed abnormal results. But confirmatory health examination about liver disease, urogenital disease seemed to contribute to confirmative diagnosis. In conclusion, we described some problems of target diseases, test items, confirmatory tests in worker's periodic health examination. So we'd like lo suggest more extensive reconsideration about adequate target diseases, test items, and confirmatory health examination and cost-benefit analysis to improve the efficacy of workers' periodic health examination.

랫드를 이용한 할로겐 화합물의 흡입독성 연구

이종윤,이성배,한정희,정용현,김현영,맹승희,임철홍,유일재,이준연,이용묵 한국산업위생학회 2000 한국산업보건학회지 Vol.10 No.2

Inhaled halogen compound was examined through micronucleus tests and toxicity tests using SD (Sprague-Dawley) rats with repeated dosages for six hours a day, five days a week, during four weeks. In four-week repeated exposure, no specific sign caused by the CF₃I compound was observed on the clinical symptoms, body weight variation, feed consumption, and urinalysis data in the testing groups with reference to the control group. In hematological and biochemical blood tests of the testing groups, the significant, but in their normal ranges, value dependences of glucose, aspartate aminotransferase, alanine aminotransferase and etc., on the halogen carbohydride concentration was observed. In histo-pathological tests, no specific lesion or concentration dependent change due to the CF₃I compound dosage was observed m both sexes of the female and male in the tested animals. But, micronucleus tests on marrow cells extracted from the tested animals which were repeatedly exposed in the CF₃I compound during four weeks, the frequencies of micronuclei were significantly increased dose-dependently compared to the control groups.