• Environmental Analysis Health and Toxicology
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• 제22권1호
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• pp.27-36
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• 2007

Cyanides and dichlorophenols were important pollutants in industrial effluents of steel, petroleum, plastics, pesticides, synthetic dye and/or fiber manufacturing. The toxic effects of cyanide and 3, 5-dichlorophenol in the unary and binary solutions to Vibrio fischeri were determined using the newly developed $N-tox^{(R)}$ bioassay system. This bioassay system relies upon the attenuation of light intensity emitted by Vibrio fischeri exposed to various pollutants including metals and organic compounds. Most of studies dealing with toxicity of pollutants concerned single chemical species, while the organisms were typically exposed to pollutant mixtures. The present study showed that the toxicity of some binary combinations of cyanide and 3, 5-dichlorophenol significantly was lower than the predicted toxicity from the addicted model. This antagonistic interaction was well explained by chemical interaction model presented in this study.

• Environmental Engineering Research
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• 제23권2호
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• pp.143-149
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• 2018

Air quality conditions and pollution status have been evaluated in the industrial area between Sharjah and Ajman border in UAE. Daily concentrations of $O_3$, CO, $NO_2$, $SO_2$, $PM_{2.5}$, $PM_{10}$, Total Volatile Organic Compounds (TVOC) and Total Suspended Particulate (TSP) have been monitored from Sept. 2015 to April 2016. The monthly average concentrations of $O_3$, CO, $NO_2$, $SO_2$, TVOC were within the UAE ambient air quality standards during the survey period. However, $PM_{10}$ and TSP levels exceeded the recommended limits in Sept. 2015, Oct. 2015 and March 2016. Temporal variations in air quality parameters showed highest levels in March 2016 for $PM_{2.5}$, $PM_{10}$, $NO_2$, TVOC and TSP, whereas $O_3$, $SO_2$ and CO showed relatively low values in this month. $PM_{2.5}$ levels in ambient air were above the EPA guideline of $35{\mu}g/m^3$ in all months. $PM_{2.5}$ was the critical ambient air pollutant with Index for Pollutant ($I_p$) values varying from 103-209, indicating Air Quality Index categories of unhealthy for sensitive groups (62.5%) to unhealthy (25%) to very unhealthy (12.5%). The $I_p$ average values of $PM_{2.5}$ decreased from Sept. 2015 to reach lowest value in Dec. 2015 before increasing gradually, peaking in March 2016. These results suggest the potential health risks associated with $PM_{2.5}$ is low in winter, where the prevailing meteorological conditions of lower temperatures, higher humidity, higher wind speed reduced particulate matter. The results revealed the industrial area is impacted by anthropogenic and natural sources of particulate matter.

• 한국농공학회지
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• 제42권1호
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• pp.73-82
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• 2000

Large quantitive of polllutants are washed into reservoirs during storm events. These polllutants contribute to eutrophication, such as algal blooms and fish kills. This study was conducted for the purpose of assessing the pollutant removal possibilities of sedimentation pool formed by deep dredging of a reservoir inlet. Water quality data were collected in the Masan reservoir, whose inlet has been dredged deep like sedimentation pool. The average concentration of chemical oxygen demand(COD) , toatal nitrogen(T-N) and total phosphrous(T-P) in the deep dredged area were 8.7 ~20.5mg/ι (T-N), 0.17~0.84mg/ι(T-P), which were 4.9%(COD), 29.0%(T-N) and 44.8%(T-P) higher than those of middle part of the reservior. The texture of sediment in the dredged area was silty loam, while that of the middle part was sandy clay loam. Organic matter contents, T-N and T-P of the bottom soil in the dredge area showed higher values than the middle part of the reservoirs. From these results, it was considered thedeep dredged area in the inlet of reservoir might play a key role to settle pollutant particulate. Based on the result of water quality analysis, deep dredging of the reservoir inlet could be assessed to reduce T-N and T-P of the reservoir about 6.5% , 8.3%, respectively. However, the effect of the sedimentation pool would be raised if the settled particles were taken into account in assessing water quality improvement for the reservoir. Accordingly, dredging of a reservoir inlet to make a shape of sedimentation pool is recommended for water quality improvement of reservoir in the stage of dredging plan.

• 한국환경과학회지
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• 제21권12호
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• pp.1495-1501
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• 2012

In this study, an experiment was conducted on influent water with low concentrations of organic matter, such as river water or secondary treatment water of a sewage treatment plant, according to HRT changes by using aerobic biofilm. In the biofilm process, as the biofilm increases in thickness, the inner membrane can be low in oxygen transfer rate and become anaerobic conditions, while the detachment of biomass from biofilm occurs. To overcome these limitations in the detachment of microorganisms in biofilm, the yarn, which was made from poly propylene(PP), was weaved and manufactured into a tube. Then, a test was carried out by injecting air so that the interior of the biofilm could create aerobic conditions. The results of the experiment showed that the removal efficiency of $TCOD_{cr}$ reached 66.1~81.2% by HRT 2hr, and 50.9 ~61.8% after HRT 1 hr. The removal efficiency of $SCOD_{cr}$ was 45.9 to 55.1% by HRT 1hr, and 26.1% in HRT 0.5hr, showing the highest removal efficiency in HRT 1hr. The SS removal efficiency was at 81.8 to 94.6%, and the effluent SS concentration was very low, indicating less than 2.2 mg/L in all HRT's. As a result, the $SCOD_{cr}$ and $NH_4{^+}$-N that were removed per specific surface area and attached to microbial biofilm showed the highest efficiency in HRT 1hr with 8.37 $gSCOD_{cr}/m^2{\cdot}d$, 2.93 $gNH_4{^+}-N/m^2{\cdot}d$. From the result of reviewing the characteristics of biofilm growth, microorganisms were found to be attached, and increased by 36 days. Later, they decreased in number through detachment, but showed a tendency to increase again 41 days later due to microbial reproduction.

• 대한공간정보학회지
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• 제6권1호
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• pp.75-90
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• 1998

본 연구에서는 하천수질관리 방안의 일환으로 수질 및 오염원등의 환경정보에 대한 데이터베이스를 구축하고, 특히 하천의 유기오염 상태를 나타내는 지표인 BOD를 중심으로 GSIS환경하에서 시간과 지점에 따라 변화되는 사항을 수치적으로는 물론 시각적으로 Simulation하였다. 또한 각종 환경관련정보의 테이터베이스 구축과 동시에 검색, 통계, 분석등에 목적을 두고 있다. 본 연구의 결과를 이용하면 일반인에게 하천의 오염상태를 쉽게 보고 이해 할 수 있게 하여 환경에 대한 관심도를 높이는 데 도움을 줄 수 있으며 돌발적인 수결오염의 발생시 대상지역 및 영향의 정도를 신속하게 파악할 수 있다. 그리고 각 지역간의 오염원현황 및 발생오염부하량의 원활한 비교와 파악이 가능하고 각 오염인자에 의한 하천의 오염의 정도를 파악할 수 있어 이에 대한 적절한 오염량 저감대책 수립의 한 기준으로 사용될 수 있을 것으로 기대된다.

• 한국산업보건학회지
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• 제29권2호
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• pp.119-140
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• 2019

Objectives: This study was based on the occurrence of a coffee roasting process-related disorder(bronchiolitis obliterans; published by NIOSH in the US) among workers exposed to chemicals called diacetyl in a coffee processing facility. Flavorings added to coffee contain diacetyl and 2,3-pentanedione, all of which are subject to exposure in a number of food manufacturing processes, including coffee roasting, grinding, and packaging. Therefore, this study aims to review the toxicity to workers related to food processing and food additive manufacturing to prevent occupational diseases. Methods: We surveyed the related literature, domestic and international references, and the status of relevant domestic and foreign professional organizations. The present situation of workers was investigated by reviewing literature on the safety and health of workers in the coffee roasting process using domestic and foreign literature and presentations. Expert advisory opinions were reflected, and experts were consulted by participating in domestic and overseas academic conferences. Results: Most of the fragrance materials for coffee were harmful and hazardous substances according to the GHS classification, and research was carried out through a second external consultation. A literature review on the measurement of air pollutant emissions from coffee roasters and the estimation of air pollutant emissions during coffee roasting examined the characteristics of pollutants emitted during coffee roasting. Conclusions: Two chemicals identified as causing bronchiolitis obliterans in the coffee roasting process are believed to explain why the disease is difficult to treat. This information can be used effectively in the future prevention of this disease. Future studies should clearly identify the potential for toxicity of alpha-diketones and the bases of OELs in relation to the occurrence of obstructive bronchiolitis, including measurement of various organic compounds and alpha-diketones from ground coffee, as well as various coffee grinds and coffee bean varieties. In particular, it is necessary to clarify the current understanding of the dose-response relationship between alpha-diketone and lung disease in workers involved in coffee roasting.

• 한국대기환경학회지
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• 제33권3호
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• pp.205-216
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• 2017

Carbonaceous aerosols such as the equivalent black carbon (eBC), the elemental carbon (EC) and the organic carbon (OC) were monitored at the Seoul Olympic Park site ($37.521^{\circ}N$, $127.124^{\circ}E$) during the KORUS-AQ 2016 campaign using a Multi Angle Absorption Photometer (MAAP) and an OCEC Analyzer. Averaged mass concentrations of eBC, EC and OC were presented as $2.46{\pm}1.52{\mu}g/m^3$, $1.01{\pm}0.60{\mu}g/m^3$ and $4.85{\pm}2.60{\mu}g/m^3$, respectively. OC/EC ratio and mass absorption cross-section (MAC) of light absorbing aerosols were calculated as 2.32 and $14.8m^2/g$, respectively. Diesel OC concentrations were estimated from a source profile of diesel vehicles as well. eBC mass concentrations measured from May $26^{th}$ to May $27^{th}$, 2016 showed 40% higher than averaged eBC mass concentrations during campaign period. $PM_{2.5}$ concentrations measured in this period were also higher than average $PM_{2.5}$ concentrations. High eBC concentrations were observed from May $29^{th}$ to May $31^{st}$, 2016 and from June $9^{th}$ to June $11^{th}$, 2016, possibly due to morning rush hour and the effect of temperature inversion at night. Diurnal variations of eBC, EC and Diesel OC showed a typical pattern of metropolitan area. In the weekend, however, diurnal variations of eBC, EC and Diesel OC mass concentrations were different from those measured in the weekday. It is expected that this study can help to understand the relationship between carbonaceous aerosols in a metropolitan area.

• 한국습지학회지
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• 제18권1호
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• pp.68-75
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• 2016

본 연구에서는 습지에 널리 적용되는 혼합토양이나 자갈여재 대신 공극율이 90% 이상으로 매우 커서 공극폐색의 염려가 적은 합성섬유를 대체여재로 적용한 수직 흐름형 컬럼습지를 제작하여 서로 다른 수리학적 체류시간, 내부순환빈도 및 오염 부하량 조건에서 축산지역 인공 강우유출수 처리시험을 수행하였다. 모든 습지에서 TSS 제거효율은 94~96%, COD 68~73%, TN 35~58% 이었다. 체류시간 등의 운전인자가 TSS와 COD 제거에 미치는 영향은 미미하였다. 그러나 질소의 경우 부하량과 체류시간, 내부순환빈도가 증가할수록 효율이 증가하였다. 특히 운전기간 동안 합성섬유의 생물학적 분해작용으로 인하여 유기물질이 다량 용출되었으며 탈질을 위한 내부공급 탄소원으로 기여하는 것으로 밝혀졌다. 그러나 용출기간은 40일 정도 지속되었으므로 그 효과는 매우 제한적이었다. 습지 내부충진 여재로서 합성섬유가 갖는 장점은 가벼우므로 구조체의 시공에 소요되는 비용을 저감할 수 있고, 비표면적이 크고 습지수명을 연장할 수 있다는 점이다.

• 해양환경안전학회지
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• 제13권2호
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• pp.103-110
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• 2007

2003년 하계 진해만의 수질개선을 위한 육상오염물질 삭감량을 산정하기 위해 생태계 모델을 적용하였다. 모델에 의해 재현된 진해만의 수질은 마산만 측의 내측에서 해양수질 등급 III을 상회하는 수준으로 나타났으며, 등급 II의 수질로 개선하기 위해서는 육상부하를 50% 삭감하는 것이 효율적인 것으로 나타났다. 진해만 전 해역을 목표수질인 화학적 산소요구량 (COD) 농도 2.0mg/L을 만족하는 조 건은 전체 육상부하의 $70\sim90%$를 삭감하거나, 전체 육상부하와 저질 용출부하의 50%를 동시에 삭감하여야 하는 것으로 나타났다. 해역 II등급을 유지하기 위해 삭감해야 할 양은 유기물과 영양염을 동시에 삭감할 경우, 유기물 (COD) 5,632kg/day, 용존무기인 481kg/day 및 용존무기질소 7,991kg/day이며, 이 때 오염부하량의 한계 즉, 환경용량은 화학적산소요구량 부하 13,112kg/day, 용존무기인 206kg/day 그리고 용존무기질소 3,425kg/day 이라고 할 수 있다.

• 유기물자원화
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• 제19권1호
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• pp.64-78
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• 2011

본 연구에서는 염분이 높은 단무지폐수를 대상으로 새로운 침지형 막분리 장치를 제작하고 기존의 소수성이 강한 폴리에틸렌 재질의 비개질 분리막과 이 소수성 분리막에 이온빔을 조사하여 친수성을 높여준 표면개질 분리막을 사용한 성능실험에서 시간에 따른 플럭스(flux)와 압력 변화, 유기물과 부유물질, 영양염류 등 오염물질의 제거 특성을 알아보았다. 간헐식 비개질막을 사용한 실험 결과, 합성폐수와는 달리 실제폐수에서는 투과 압력이 급격히 증가하여 심한 파울링(fouling) 현상이 일어남을 알 수 있으며 이는 실제폐수에 존재하는 첨가제 등 고분자물질과 염분에 의한 영향으로 추정된다. 약품세정 후의 막과 물세정 후의 막의 압력과 플럭스 변화 실험에서 오염된 막을 재생하기 위해 약품세정이 반드시 필요하며 막 운전시 연속식보다는 간헐식으로 운전하는 것이 성능이 더 우수함을 알 수 있었다. 또한 개질막의 경우가 비개질막의 경우보다 파울링에 도달하는 시간이 약 6배가 크므로 개질막의 경우가 막의 교체 비용을 1/6로 줄일 수 있다. 표면개질 분리막과 비개질 분리막 모두 처리수는 대체로 양호한 수질을 나타내고 있으며 특히 SS 제거, 질소 및 인 제거에도 탁월한 성능을 나타내고 있다.