제련소 주변 지역 주민들의 혈중 중금속 농도와 혈압과의 관련성

엄상용(Sang-Yong Eom),임동혁(Dong-Hyuk Yim),문선인(Sun-In Moon),버룰마(Bolormaa Ochirpurev),최영숙(Young-Sook Choi),박충희(Choong-Hee Park),김근배(Guen-Bae Kim),유승도(Seung-Do Yu),최병선(Byung-Sun Choi),박정덕(Jung-Duck Park),김용대 한국농촌의학 지역보건학회 2017 농촌의학·지역보건 Vol.42 No.1

이 연구는 장항제련소 주변 지역 주민들을 대상으로 중금속 노출에 의한 인체영향을 파악하기 위해 수행된 환경역학조사 결과 중 혈중 중금속 농도와 혈압 사이의 관계를 평가하기 위해 수행되었다. 이 연구에는 제련소에서 4㎞ 이내에 거주하는 570명의 30세 이상 성인 남녀가 포함되었으며 남녀별로 혈중 카드뮴, 수은 및 납 농도를 각각 3분위로 나눈 후 군별로 수축기 및 이완기 혈압의 차이를 각각 비교하였다. 또한, 다중회귀분석을 통하여 남녀별로 수축기 및 이완기혈압에 영향을 주는 위험요인으로서의 중금속을 파악하였다. 남자의 경우는 혈중 카드뮴과 수은의 농도별 군에 따라 수축기 혈압 및 이완기 혈압의 평균에 유의한 차이를 보였으나 여자의 경우는 모든 중금속의 3분위군에서 수축기 및 이온기 혈압의 평균이 유의한 차이를 보이지 않았다. 다중 회귀 분석의 결과에서는 남자의 경우 연령과 체질량 지수 그리고 혈중 카드뮴 농도가 혈압에 영향을 주는 위험요인으로 나타났고, 여자의 경우는 연령과 체질량 지수, 음주 및 흡연, 그리고 혈중 수은이 혈압에 유의한 영향을 주었다. 종합해보면, 장항 제련소 근처에 거주하는 주민들은 일반인구집단과 비교해 볼 때, 매우 높은 농도의 혈중 카드뮴, 납 수치를 보여 이들은 과거 직업적 또는 환경적으로 고농도의 중금속에 노출된 것으로 판단되며, 이러한 고농도 노출 집단에서의 유해 중금속 노출, 특히 카드뮴과 수은이 혈압 상승에 유의한 영향을 주는 것으로 확인되었다. 따라서 이들을 대상으로 추가적인 중금속 노출을 예방하기 위한 노력과 혈압 및 심뇌혈관질환 발생에 대한 지속적인 모니터링이 이루어져야 할 것으로 판단된다. Objectives: This study was conducted to evaluate a relationship between the blood concentrations of toxic metals and the blood pressure in people living near the copper smelter. Methods: The study included 570 adults living within 4km of the smelter. We compared systolic and diastolic blood pressure between tertiary groups for blood cadmium, mercury and lead levels, respectively. Multiple regression analysis was performed to identify risk factors affecting systolic and diastolic blood pressures. Results: In male subjects, there is a significant difference in the mean of systolic and diastolic blood pressure between tertiary groups of blood cadmium and mercury levels, but in women, there was no significant difference in the mean systolic and diastolic blood pressures in all tertiary groups of heavy metals. The results of multiple regression analysis showed that age, BMI, and cadmium concentration in men were risk factors for blood pressure. In women, age and BMI, drinking and smoking, and blood mercury were significantly influenced to blood pressure. Conclusions: Residents living near the Janghang smelter showed high concentrations of blood lead and cadmium, suggesting that they were exposed to high concentrations of heavy metals released from the smelter in the past. Such exposure may have caused some blood pressure increase. Especially, the concentration of cadmium in the case of men and the concentration of mercury in blood in the case of women were found to be significantly related to the increase of blood pressure. The local population should be advised to make efforts to reduce exposure to environmental contaminants, in order to minimize cardiovascular disease, and to pay close attention to any health problems possibly related to toxic metal exposure.

Thermogravimetric Analysis of Rice Husk Flour for a New Raw Material of Lignocellulosic FiberThermoplastic Polymer Composites

Kim, Hyun Joong,Eom, Young Guen 한국목재공학회 2001 목재공학 Vol.29 No.3

Rice husk flours were analyzed by chemical composition and thermogravimetric methods in nitrogen atmosphere to discuss its feasibility as a raw material for manufacturing agricultural lignocellulosic fiber-thermoplastic polymer composite. It was revealed in the chemical composition analysis that rice husk flour was composed of moisture, 5.0%; lignin, 21.6%; holocellulose, 60.8%; ash, 12.6%. In the thermogravimetric analysis (TGA), thermal decomposition behavior of rice husk flour from room temperature to 350℃ was similar to that of wood flour, but rice husk flour was more thermally stable from 350 to 800℃ than wood flour because of higher silica content in the rice husk flour and smaller particle size of rice husk flour. The activation energy of thermal decomposition was evaluated using Flynn & Wall expression. As the thermal decomposition proceeded in rice husk flour, the activation energy of thermal decomposition appeared almost constant up to α = 0.25, but thereafter increased. Activation energy of thermal decomposition in wood flour, however, decreased steeply up to α = 0.3, but thereafter remained almost constant. From the results, rice husk flour was thought be a substitute for wood flour in manufacturing agricultural lignocellulosic fiber-thermoplastic polymer composite in the aspect of thermal decomposition.

Association of Smoking History with Cancer Recurrence and Survival in Stage III–IV Male Gastric Cancer Patients

Han, Mi Ah,Kim, Young-Woo,Choi, Il Ju,Oh, Myueng Guen,Kim, Chan Gyoo,Lee, Jong Yeul,Cho, Soo-Jeong,Eom, Bang Wool,Yoon, Hong Man,Ryu, Keun Won American Association for Cancer Research 2013 Cancer epidemiology, biomarkers & prevention Vol.22 No.10

<P><B>Background:</B> Smoking and drinking alcohol are major risk factors for cancer development, and we investigated their effects on gastric cancer prognosis following initial resection.</P><P><B>Methods:</B> Data from male patients with stage III–IV gastric adenocarcinoma who underwent surgery between 2001 and 2006 were retrospectively reviewed. Patients were followed up until 2011. Kaplan–Meier plots and Cox proportional hazards regressions were applied for survival rates.</P><P><B>Results:</B> Among 238 patients, 151 (63.4%) smoked and 146 (61.3%) drank alcohol. Current smokers had an increased risk of cancer recurrence or death from any cause [adjusted HR (aHR), 1.94; 95% confidence interval (CI), 1.18–3.21], cancer recurrence (aHR, 1.89; 95% CI, 1.12–3.21), and overall mortality (aHR, 2.14; 95% CI, 1.23–3.73) compared with never-smokers. Patients with a lifetime cigarette smoking of <40 and ≥40 pack-years had increased cancer recurrence or death from any cause (aHR, 1.72 and 2.43, respectively; 95% CI, 1.03–2.86 and 1.38–4.30, respectively), cancer recurrence (aHR, 1.63 and 2.61, respectively; 95% CI, 0.95–2.79 and 1.43–4.77, respectively), and overall mortality (aHR, 1.92 and 2.75, respectively; 95% CI, 1.09–3.38 and 1.47–5.12, respectively) compared with never-smokers. However, drinking alcohol was not associated with postsurgery survival.</P><P><B>Conclusions:</B> Cigarette-smoking history at the time of diagnosis, but not drinking history, is associated with cancer recurrence and poor survival after surgery in male patients with stage III–IV gastric cancer.</P><P><B>Impact:</B> These findings encourage physicians to advise patients with gastric cancer to stop smoking to obtain a general health benefit and likely improvement in the gastric cancer course. <I>Cancer Epidemiol Biomarkers Prev; 22(10); 1805–12. ©2013 AACR</I>.</P>

졸참나무 지재 (枝材) 섬유에 관한 연구

이필우,엄영근 ( Phil Woo Lee,Young Guen Eom ) 한국산림과학회 1983 한국산림과학회지 Vol.60 No.1

According to the worldwide decreasing tendency in raw materials and increase in wood demands since 1970, the efficient utilization of raw materials was required internationally. Therefore this study dealt with the dimensional characteristics of branchwood fiber of Ouercus serrata Thunb for the complete utilization of whole tree. According to the branch individuals, parts and positions within a tree, fiber length, width and wall-thickness were measured. The results obtained are as follows: 1) As the height of individual branchwood increases from ground toward, fiber length and width, and wall-thickness decreased linearly and their regression equations obtained, were Y=770.03-22.643X, Y=27.444-0.71385X and Y=12.308-0.57320X respectively 2) From the main stem to branch in distal direction, fiber length, width and wall-thickness linearly decreased and their regression equations obtained were Y=752.70-0.6724X, Y=26.152-0.0084867X and Y=11.258-0.006205X, respectively. 3) As the radial direction from pith to hark increases, fiber length, width and wall-thickness increased linearly and their regression equations obtained were Y=679.73+11.231X Y=25.382+0.0925X and Y=10.521+0.11787X, respectively. 4) Mean value of fiber length, width and wall-thickness were 625-765, 26 and 11㎛, respectively.

155Mb/s급 동기식 Add-Drop Multiplexer(ADM-155)의 구현

이동춘(Dong Choon Lee),엄두섭(Doo Seop Eom),김춘희(Choon Hee Kim),최지영(Ji Young Choe),김홍주(Hong Joo Kim),김재근(Jae Guen Kim) 한국통신학회 1993 한국통신학회 학술대회논문집 Vol.12 No.1

Mg-Zn-(Mn)-Ca 합금의 미세조직 및 기계적 성질

엄정필,차동득,임수근,허보영 ( Jeong Pil Eom,Dong Deuk Cha,Su Guen Lim,Bo Young Hur ) 한국주조공학회 1997 한국주조공학회지 Vol.17 No.6

N/A The microstructure and tensile properties of Mg-Zn-Ca and Mg-Zn-Mn-Ca alloys have been investigated. The alloys were obtained by melting in a low carbon crucible coated with boron nitride under an Ar gas atmosphere to prevent oxidation and combustion. The Mg alloy melt was cast into the metallic mold at room temperature, and cooling part was located at the bottom of mold. The phase formed during solidification of the Mg-Zn-(Mn) alloys containing 0.5%Ca is Ca₂Mg_6Zn₃,. The yield strength and ultimate tensile strength of the alloys increased with increasing Zn content, but the ductility did not change with increasing Zn content. The addition of Mn improves the yield strength and ultimate tensile strength of the alloys, but the ductility did not change. Tensile fracture of the alloys revealed brittle failure, with cracking along the Ca₂Mg_6Zn₃, phase. The variation of stress with strain obeyed the relationship of the σ=Kε. (Received October 21, 1997)

Ar 가스 분위기에서 제조한 Mg-Zn-(Mn) 합금의 미세조직

엄정필,임수근,허보영 ( Jeong Pil Eom,Su Guen Lim,Bo Young Hur ) 한국주조공학회 1996 한국주조공학회지 Vol.16 No.4

N/A The microstructure of Mg-1∼6wt%Zn, Mg-1.5wt%Mn and Mg-3,6wt%Zn-lwt%Mn alloys were investigated by means of optical microscopy, scanning electron microscopy and energy dispersive spectroscopy. The liquid Mg alloys were tasted into the metallic mold at room temperature, and cooling part was located at the bottom of mold. The microstructure of Mg-Zn cast alloys revealed that MgZn compounds were around the secondary dendrite arms. Scanning electron microscopy and energy dispersive spectroscopy showed that the composition of MgZn compound was Mg-77wt%Zn. The addition of Mn in Mg-Zn alloys refined the grain size in as tasted alloys. Manganese additions also increased the Vickers hardness.

UV-curing Behaviors and Mechanical Properties of UV-cured polylactic Acid, PLA

Seung Woo Lee,Ji Won Park,Cho Hee Park,Hyun Joong Kim,Young Guen Eom 한국목재공학회 2013 목재공학 Vol.41 No.2

UV curing was introduced via a chemical treatment by adding small amounts of a hexafunctional acrylic monomer and a photoinitiator to improve the mechanical properties of PLA. This study also employed a semi-interpenetrated structured polymer network through the process of UV-curing. The UV curing be-haviors were investigated using FTIR-ATR spectroscopy and gel fraction determination. Also, the tensile strength was investigated with different hexafunctional acrylic monomer contents and UV doses. The re-sults showed that the crosslinking of UV-induced chemically treated PLA started at a low content of hex-afunctional acrylic monomer, resulting in a significant improvement of the mechanical properties compared to those of neat PLA due to crosslinking.