Evaluation on Four Volatile Organic Compounds (VOCs) Contents in the Groundwater and Their Human Risk Level

Song, Dahee,Park, Sunhwa,Jeon, Sang-Ho,Hwang, Jong Yeon,Kim, Moonsu,Jo, Hun-Je,Kim, Deok-Hyun,Lee, Gyeong-Mi,Kim, Ki-In,Kim, Hye-Jin,Kim, Tae-Seung,Chung, Hyen Mi,Kim, Hyun-Koo 한국토양비료학회 2017 한국토양비료학회지 Vol.50 No.4

In this study, we monitored 4 volatile organic compounds (VOCs) such as chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane in groundwater samples to determine the detection frequency and their concentrations and evaluated the health risk level considering ingestion, inhalation, and skin contact. 75 groundwater wells were selected. 24 wells were from monitoring background groundwater quality level and 51 wells were from monitoring groundwater quality level in industrial or contamination source area. In the results, the detection frequency for chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane was 42.3%, 8.1%, 6.0%, and 3.4%, respectively. The average concentrations of VOCs were high in the order of chloroform ($1.7{\mu}g\;L^{-1}$), dichloromethane ($0.08{\mu}g\;L^{-1}$), tetrachloromethane ($0.05{\mu}g\;L^{-1}$), and 1,2-dichloroethane ($0.05{\mu}g\;L^{-1}$). Chloroform had the highest detection frequency and average detection concentration. In the contaminated groundwater, the detection frequency of VOCs was high in the order of chloroform, dichloromethane, 1,2-dchloroethane, and tetrachloromethane. The average concentrations for chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane were $2.23{\mu}g\;L^{-1}$, $0.08{\mu}g\;L^{-1}$, $0.07{\mu}g\;L^{-1}$, and $0.06{\mu}g\;L^{-1}$, respectively. All the 4 compounds were detected at industrial complex and storage tank area. The maximum concentration of chloroform, dichloromethane, and 1,2-dichloroethane was detected at industrial complex area. Especially, the maximum concentration of chloroform and dichloromethane was detected at a chemical factory area. In the uncontaminated groundwater, the detection frequency of VOCs was high in the order of chloroform, dichloromethane, and 1,2-dchloroethane and tetrachloromethane was not detected. The average concentrations for chloroform, dichloromethane, and 1,2-dichloroethane were $0.57{\mu}g\;L^{-1}$, $0.07{\mu}g\;L^{-1}$, and $0.03{\mu}g\;L^{-1}$, respectively. Although chloroform in the uncontaminated groundwater was detected the most, the concentration of chloroform was not exceeding water quality standards. By land use, the maximum detection frequency of 1,2-dichloroethane was found near a traffic area. For human risk assessment, the cancer risk for the 4 VOCs was $10^{-6}{\sim}10^{-9}$, while the non-cancer risk (HQ value) for the 4 VOCs is $10^{-2}{\sim}10^{-3}$.

Simultaneous Analysis of 13 Pesticides in Groundwater and Evaluation of its Persistent Characteristics

Dahee Song,Sunhwa Park,Sang-Ho Jeon,Ki-In Kim,Jong Yeon Hwang,Moonsu Kim,Hun-Je Jo,Deok-hyun Kim,Gyeong-Mi Lee,Hye-Jin Kim,Tae-Seung Kim,Hyen Mi Chung,Hyun-Koo Kim 한국토양비료학회 2017 한국토양비료학회지 Vol.50 No.5

For this study, groundwater samples for 3 years from 2011 through 2013 were collected at 106 groundwater monitoring site in Korea. These groundwater samples were analyzed for 13 pesticides such as cabofuran, pentachlorobenzene, hexachlorobenzene, simazine, atrazine, lindane (gamma-HCH), alachlor, heptachlor, chlordane (total), endosulfan (1, 2), dieldrin, endrin, 4,4-DDT. The objectives of this study were to determine the detection frequency and their concentrations of 13 pesticides and evaluate the health risk level considering ingestion, inhalation, and skin contact using concentrations of 13 pesticides in groundwater samples. An analysis was used for the simultaneous determination for 13 pesticides using GC-MS. GC-MS was performed on HP-5ms, using helium (1 ml min<SUP>-1</SUP>) as carrier gas. The average recoveries of the pesticides were from 92.8% to 120.8%. The limits of detection (LODs) were between 0.004 μg L<SUP>-1</SUP> and 0.118 μg L<SUP>-1</SUP> and the limits of quantification (LOQs) were between 0.012 μg L<SUP>-1</SUP> and 0.354 μg L<SUP>-1</SUP>. 106 groundwater wells were selected. 54 wells were from well to monitor background groundwater quality and 52 wells were from well to monitor groundwater quality in industrial or contamination source area. Eight pesticides including pentachlorobenzene, lindane (Gamma-HCH), heptachlor, chlordane (total), Endosulfan (1, 2), dieldrin, endrin, and 4,4-DDT were not detected in groundwater samples. The detection frequency for hexachlorobenzene, alachlor, carbofuran and simazine was 23.4%, 11.4%, 7.3%, and 1.0%, respectively. Atrazine was detected once in 2011. The average concentrations were 0.00423 μg L<SUP>-1</SUP> for carbofuran, 0.000243 μg L<SUP>-1</SUP> for alachlor, 0.00015 μg L<SUP>-1</SUP> for simazine, and 0.00001 μg L<SUP>-1</SUP> for hexachlorobenzene. The detection frequency of hexachlorobenzene was high, but the average concentration was low. In the contaminated groundwater, the detection frequency for hexachlorobenzene, alachlor, carbofuran, simazine and atrazine was 26.1%, 21.3%, 7.1%, 1.9% and 0.3%, respectively. In the uncontaminated groundwater, detection frequency for hexachlorobenzene, carbofuran and alachlor were 20.2%, 7.5%, and 1.9% respectively. Simazine and atrazine were not detected at uncontaminated groundwater wells. According to the purpose of groundwater use, atrazine was detected for agricultural groundwater use. Hexachlorobenzene showed high detection frequency at agricultural groundwater use area where the animal feeding area and golf course area were located. Alachlor showed more than 50% detection frequency at cropping area, pollution concern river area, and golf course area. Atrazine was detected in agricultural water use area. By land use, the maximum detection frequency of alachlor was found near an orchard. For human risk assessment, the cancer risk for the 5 pesticides was between 10<SUP>-7</SUP> and 10<SUP>-10</SUP>, while the non-cancer risk (HQ value) was between 10<SUP>-4</SUP> and 10<SUP>-6</SUP>. For conclusion, these monitoring study needs to continue because of the possibility of groundwater contamination based on various purpose of groundwater use.

Evaluation on Four Volatile Organic Compounds (VOCs) Contents in the Groundwater and Their Human Risk Level

Dahee Song,Sunhwa Park,Sang-Ho Jeon,Jong Yeon Hwang,Moonsu Kim,Hun-Je Jo,Deok-Hyun Kim,Gyeong-Mi Lee,Ki-In Kim,Hye-Jin Kim,Tae-Seung Kim,Hyen Mi Chung,Hyun-Koo Kim 한국토양비료학회 2017 한국토양비료학회지 Vol.50 No.4

In this study, we monitored 4 volatile organic compounds (VOCs) such as chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane in groundwater samples to determine the detection frequency and their concentrations and evaluated the health risk level considering ingestion, inhalation, and skin contact. 75 groundwater wells were selected. 24 wells were from monitoring background groundwater quality level and 51 wells were from monitoring groundwater quality level in industrial or contamination source area. In the results, the detection frequency for chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane was 42.3%, 8.1%, 6.0%, and 3.4%, respectively. The average concentrations of VOCs were high in the order of chloroform (1.7 μg L<SUP>-1</SUP>), dichloromethane (0.08 μg L<SUP>-1</SUP>), tetrachloromethane (0.05 μg L<SUP>-1</SUP>), and 1,2-dichloroethane (0.05 μg L<SUP>-1</SUP>). Chloroform had the highest detection frequency and average detection concentration. In the contaminated groundwater, the detection frequency of VOCs was high in the order of chloroform, dichloromethane, 1,2-dchloroethane, and tetrachloromethane. The average concentrations for chloroform, dichloromethane, 1,2-dichloroethane, and tetrachloromethane were 2.23 μg L<SUP>-1</SUP>, 0.08 μg L<SUP>-1</SUP>, 0.07 μg L<SUP>-1</SUP>, and 0.06 μg L<SUP>-1</SUP>, respectively. All the 4 compounds were detected at industrial complex and storage tank area. The maximum concentration of chloroform, dichloromethane, and 1,2-dichloroethane was detected at industrial complex area. Especially, the maximum concentration of chloroform and dichloromethane was detected at a chemical factory area. In the uncontaminated groundwater, the detection frequency of VOCs was high in the order of chloroform, dichloromethane, and 1,2-dchloroethane and tetrachloromethane was not detected. The average concentrations for chloroform, dichloromethane, and 1,2-dichloroethane were 0.57 μg L<SUP>-1</SUP>, 0.07 μg L<SUP>-1</SUP>, and 0.03 μg L<SUP>-1</SUP>, respectively. Although chloroform in the uncontaminated groundwater was detected the most, the concentration of chloroform was not exceeding water quality standards. By land use, the maximum detection frequency of 1,2-dichloroethane was found near a traffic area. For human risk assessment, the cancer risk for the 4 VOCs was 1<SUP>0-6</SUP>~10<SUP>-9</SUP>, while the non-cancer risk (HQ value) for the 4 VOCs is 10<SUP>-2</SUP>~10<SUP>-3</SUP>.

Simultaneous Analysis of 13 Pesticides in Groundwater and Evaluation of its Persistent Characteristics

Song, Dahee,Park, Sunhwa,Jeon, Sang-Ho,Kim, Ki-In,Hwang, Jong Yeon,Kim, Moonsu,Jo, Hun-Je,Kim, Deok-hyun,Lee, Gyeong-Mi,Kim, Hye-Jin,Kim, Tae-Seung,Chung, Hyen Mi,Kim, Hyun-Koo 한국토양비료학회 2017 한국토양비료학회지 Vol.50 No.5

For this study, groundwater samples for 3 years from 2011 through 2013 were collected at 106 groundwater monitoring site in Korea. These groundwater samples were analyzed for 13 pesticides such as cabofuran, pentachlorobenzene, hexachlorobenzene, simazine, atrazine, lindane (gamma-HCH), alachlor, heptachlor, chlordane (total), endosulfan (1, 2), dieldrin, endrin, 4,4-DDT. The objectives of this study were to determine the detection frequency and their concentrations of 13 pesticides and evaluate the health risk level considering ingestion, inhalation, and skin contact using concentrations of 13 pesticides in groundwater samples. An analysis was used for the simultaneous determination for 13 pesticides using GC-MS. GC-MS was performed on HP-5ms, using helium ($1ml\;min^{-1}$) as carrier gas. The average recoveries of the pesticides were from 92.8% to 120.8%. The limits of detection (LODs) were between $0.004{\mu}g\;L^{-1}$ and $0.118{\mu}g\;L^{-1}$ and the limits of quantification (LOQs) were between $0.012{\mu}g\;L^{-1}$ and $0.354{\mu}g\;L^{-1}$. 106 groundwater wells were selected. 54 wells were from well to monitor background groundwater quality and 52 wells were from well to monitor groundwater quality in industrial or contamination source area. Eight pesticides including pentachlorobenzene, lindane (Gamma-HCH), heptachlor, chlordane (total), Endosulfan (1, 2), dieldrin, endrin, and 4,4-DDT were not detected in groundwater samples. The detection frequency for hexachlorobenzene, alachlor, carbofuran and simazine was 23.4%, 11.4%, 7.3%, and 1.0%, respectively. Atrazine was detected once in 2011. The average concentrations were $0.00423{\mu}g\;L^{-1}$ for carbofuran, $0.000243{\mu}g\;L^{-1}$ for alachlor, $0.00015{\mu}g\;L^{-1}$ for simazine, and $0.00001{\mu}g\;L^{-1}$ for hexachlorobenzene. The detection frequency of hexachlorobenzene was high, but the average concentration was low. In the contaminated groundwater, the detection frequency for hexachlorobenzene, alachlor, carbofuran, simazine and atrazine was 26.1%, 21.3%, 7.1%, 1.9% and 0.3%, respectively. In the uncontaminated groundwater, detection frequency for hexachlorobenzene, carbofuran and alachlor were 20.2%, 7.5%, and 1.9% respectively. Simazine and atrazine were not detected at uncontaminated groundwater wells. According to the purpose of groundwater use, atrazine was detected for agricultural groundwater use. Hexachlorobenzene showed high detection frequency at agricultural groundwater use area where the animal feeding area and golf course area were located. Alachlor showed more than 50% detection frequency at cropping area, pollution concern river area, and golf course area. Atrazine was detected in agricultural water use area. By land use, the maximum detection frequency of alachlor was found near an orchard. For human risk assessment, the cancer risk for the 5 pesticides was between $10^{-7}$ and $10^{-10}$, while the non-cancer risk (HQ value) was between $10^{-4}$ and $10^{-6}$. For conclusion, these monitoring study needs to continue because of the possibility of groundwater contamination based on various purpose of groundwater use.

S-77 : Recurrent Duodenal Stricture and Duodenal Phytobezoar After Billoth I Operation: A Case Report

( Dahee Heo ),( Hyun Joo Song ),( Soo Young Na ),( Sun Jin Boo ),( Heung Up Kim ) 대한내과학회 2013 대한내과학회 추계학술대회 Vol.2013 No.1

Introduction: Phytobezoars are conglomerates of non-digestible vegetable matter in the gastrointestinal (GI) tract that may be insidious or symptomatic with general GI manifestations. There have been only a few case reports of phytobezoars in the literature. We report a rare case of recurrent duodenal stricture and duodenal bezoar which was detected following Billoth I operation for early gastric cancer (EGC). Case Report: A 74-year-old female patient presented at our clinic with a 2-day history of intense epigastric pain. Vomiting developed after water intake, and there was no bowel movement or gas passing. The patient had been diagnosed with EGC through a routine health workup 7 months prior to this presentation. Histopathologic examination of the specimen taken by endoscopic ultrasonography revealed a well-differentiated adenocarcinoma, type I, mucosal cancer (T1aN0Mx). Endoscopic submucosal dissection was indicated for the patient; however, she decided to undergo a laparoscopic distal gastrectomy (Billoth I). One month after the operation, she was diagnosed with anastomosis site stricture and received endoscopic balloon dilatation twice. Plain abdominal X-rays showed that there were dilatation of the stomach and gaseous patterns throughout the bowel. Computed tomography of the abdomen and pelvis showed an abruptly narrowed transition zone at the junction of the third and the fourth duodenum. At endoscopy, a 3.5-cm phytobezoar was found in the third portion of the duodenum. Endoscopic removal along with coke intake was tried. However, endoscopic removal was incomplete due to the large size of phytobezoar and a narrow endoscopic field. On the seventh hospital day, a third endoscopic trial was performed, but no phytobezoars were detected. She complained of recurrent abdominal pain thereafter. Computed tomography of the abdomen and pelvis showed a partially destroyed phytobezoar was obstructing the proximal ileum. The phytobezoar was removed through exploratory laparotomy.

시각적 단서를 이용한 복합이용시설의 길안내 시스템 최적화

서다희(Dahee Seo),송찬희(Chanhee Song),이상은(Sangeun Lee),허영복(Yeongbok Heo),이지언(Jieon Lee),이재길(Jae-gil Lee) 한국HCI학회 2024 한국HCI학회 학술대회 Vol.2024 No.1

Effect of Al₂O₃ ceramic fillers in LiNi_1/3Co_1/3Mn_1/3O₂ cathodes for improving high-voltage cycling and rate capability performance

Jin, Dahee,Song, Danoh,Friesen, Alex,Lee, Yong Min,Ryou, Myung-Hyun Pergamon Press 2018 Electrochimica Acta Vol. No.

<P><B>Abstract</B></P> <P>To improve the electrochemical properties of LiNi<SUB>1/3</SUB>Co<SUB>1/3</SUB>Mn<SUB>1/3</SUB>O<SUB>2</SUB> (NCM) under the high-voltage operating condition of 4.5 V, 0.5 wt.% of alumina (Al<SUB>2</SUB>O<SUB>3</SUB>) was introduced as a ceramic filler during NCM cathode preparation. Uniformly dispersed Al<SUB>2</SUB>O<SUB>3</SUB> over the entire area of the NCM cathodes efficiently stabilized the oxidative decomposition of the liquid electrolyte up to 5.3 V. This behavior hindered the formation of a thick surface film on the NCM cathodes after high-voltage operation (4.5 V). The Al<SUB>2</SUB>O<SUB>3</SUB>-containing NCM cathodes (NCM/Al<SUB>2</SUB>O<SUB>3</SUB>) revealed much smaller total cell resistance compared to the bare NCM cathodes, resulting in improved cycle performance and rate capabilities, which were identified as a facilitated Li<SUP>+</SUP> diffusion in presence of the Al<SUB>2</SUB>O<SUB>3</SUB> particles. NCM/Al<SUB>2</SUB>O<SUB>3</SUB> showed a 29.4% improvement over the bare NCM (79.3 and 112.3 mAhh g<SUP>−1</SUP> for bare NCM and NCM/Al<SUB>2</SUB>O<SUB>3</SUB>, respectively, after the 100<SUP>th</SUP> cycle) at 3C (4.3 V cutoff, C/2 for charging and 3C for discharging processes) and a 53.5% improvement (35.0 and 75.3 mAhh g<SUP>−1</SUP> for NCM/Al<SUB>2</SUB>O<SUB>3</SUB> and bare NCM, respectively) at 5C (4.5 V cutoff).</P> <P><B>Highlights</B></P> <P> <UL> <LI> Alumina (Al<SUB>2</SUB>O<SUB>3</SUB>) was introduced as ceramic filler during NCM cathode preparation. </LI> <LI> Al<SUB>2</SUB>O<SUB>3</SUB> stabilized oxidative decomposition of liquid electrolyte (∼5.3 V vs. Li/Li<SUP>+</SUP>). </LI> <LI> Al<SUB>2</SUB>O<SUB>3</SUB> showed significant improvement in high voltage operating condition. </LI> <LI> Al<SUB>2</SUB>O<SUB>3</SUB> showed significant improvement in cycle performance and rate capability. </LI> </UL> </P>

Wavelet을 이용한 동잡음 판단에 관한 연구

반다희(Dahee Ban),손혁재(Hyukjae Son),송성호(Seongho Song),권성오(Sungoh Kwon) 한국통신학회 2014 한국통신학회 학술대회논문집 Vol.2014 No.6

실내 3차원 소공간 내의 위치추정에 관한 연구

송성호(Seongho Song),반다희(Dahee Ban),박갑문(Kapmoon Park),김연옥(Yeonok Kim),권성오(Sungoh Kwon) 한국통신학회 2015 한국통신학회 학술대회논문집 Vol.2015 No.1

전고체 전지 장기 수명 개선을 위한 NCM/LFP 블랜딩 양극 물질 최적화 연구

송영웅(Youngwoong Song),김민영(Minyoung Kim),허국진(Kookjin Heo),황다희(Dahee Hwang),이종관(Jongkwan Lee),김재국(Jaekook Kim),임진섭(Jinsub Lim) 한국전지학회 2021 한국전지학회지 Vol.1 No.1

본 논문에서 층상구조의 NCM70과 올리빈 구조의 LiFePO4를 다양한 비율로 혼합하여 제조된 블랜딩 양극 물질의 전기화학적 특성을 보고한다. XRD 분석을 통해 블랜딩 양극 물질은 NCM과 LFP 구조가 혼합된 상으로 존재함을 확인하였다. 산화물계 무기 고체 전해질과 고분자 고체 전해질이 결합된 복합 고체전해질을 이용하여 전고체 전지를 제조하여 실험을 진행한 결과, NCM70의 사이클 특성을 LFP와 블랜딩을 통해 향상시킬 수 있다. We report the electrochemical properties of blended cathode materials prepared by mixing layered structure NCM70 and olivine structure LiFePO4 by various ratios. Through XRD analysis, it was confirmed that the blending cathode material exists as a mixed phase of NCM and LFP structures. As results of the systematic experiment by manufacturing an all-solid-state lithium battery (ASLB) using a composite solid electrolyte in which an oxide-based inorganic solid electrolyte and a polymer solid electrolyte were combined, it was possible to improve the deterioration phenomenon occurring during the cycle of NCM70 by blending with LFP.