• 제목/요약/키워드: environmental samples

검색결과 5,482건 처리시간 0.033초

GC/MS를 이용한 수질환경시료 중 personal care products의 분석 (Determination of personal care products in aquatic environmental samples by GC/MS)

  • 이인정;이철구;허성남;이재관
    • 분석과학
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    • 제23권5호
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    • pp.477-484
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    • 2010
  • 항균제 및 자외선 차단물질, 유기인계 난연제 등과 같은 personal care products는 개인이 일상생활에서 광범위하게 사용하는 비누, 화장품, 치약 등에 포함된 합성유기화합물로 하 폐수 처리시설에서 완벽하게 제거되지 않고 생활하수에 포함된 상당수의 양이 환경 중으로 배출되고 있다. 외국사례의 경우 하천, 해양, 토양, 저질, 생물상 등 다양한 환경매체에서 검출되고 있으며, 잔류성 생물농축성이 있어 지속적으로 노출시 생태계 및 인간의 건강에 심각한 영향을 끼칠 우려가 있다. 본 연구에서는 수질환경시료 중 15종의 personal care products를 액-액추출하여 GC/MS로 분석하였으며, 방법검출한계는 $0.004\sim0.273\;{\mu}g/L$의 범위를 나타내었다. 하천수에서는 TCEP, TCPP 등 2종이 검출되었으며, 하수처리장 시료에서는 triclosan, 4-MBC, EHMC, BP-3, TCEP, TPP, TBEP 등 7종이 검출되었다.

Profiling Patterns of Volatile Organic Compounds in Intact, Senescent, and Litter Red Pine (Pinus densiflora Sieb. et Zucc.) Needles in Winter

  • CHOI, Won-Sil;YANG, Seung-Ok;LEE, Ji-Hyun;CHOI, Eun-Ji;KIM, Yun-Hee;YANG, Jiyoon;PARK, Mi-Jin
    • Journal of the Korean Wood Science and Technology
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    • 제48권5호
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    • pp.591-607
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    • 2020
  • This study was aimed to investigate the changes of chemical composition of the volatile organic compounds (VOCs) emitted from red pine needles in the process of needle abscission or senescence. The VOCs in intact, senescent, and litter red pine needle samples were analyzed by headspace-solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC/MS). And then, multivariate statistical interpretation of the processed data sets was conducted to investigate similarities and dissimilarities of the needle samples. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were used to investigate the dataset structure and discrimination between samples, respectively. From the data preview, the levels of major components of VOCs from needles were not significantly different between needle samples. By PCA investigation, the data reduction according to classification based on the chlorophyll a / chlorophyll b (Ca/Cb) ratio were found to be ideal for differentiating intact, senescent, and litter needles. The following OPLS-DA taking Ca/Cb ratio as y-variables showed that needle samples were well grouped on score plot and had the significant discriminant compounds, respectively. Several compounds had significantly correlated with Ca/Cb ratio in a bivariate correlation analysis. Notably, the litter needles had a higher content of oxidized compounds than the intact needles. In summary, we found that chemical compositions of VOCs between intact, senescent, and litter needles are different each other and several compounds reflect characteristic of needle.

Mechanical behaviour of waste powdered tiles and Portland cement treated soft clay

  • Al-Bared, Mohammed A.M.;Harahap, Indra S.H.;Marto, Aminaton;Abad, Seyed Vahid Alavi Nezhad Khalil;Mustaffa, Zahiraniza;Ali, Montasir O.A.
    • Geomechanics and Engineering
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    • 제19권1호
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    • pp.37-47
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    • 2019
  • The main objective of this study is to evaluate and compare the efficiency of ordinary Portland cement (OPC) in enhancing the unconfined compressive strength of soft soil alone and soft soil mixed with recycled tiles. The recycled tiles have been used to treat soft soil in a previous research by Al-Bared et al. (2019) and the results showed significant improvement, but the improved strength value was for samples treated with low cement content (2%). Hence, OPC is added alone in this research in various proportions and together with the optimum value of recycled tiles in order to investigate the improvement in the strength. The results of the compaction tests of the soft soil treated with recycled tiles and 2, 4, and 6% OPC revealed an increment in the maximum dry density and a decrement in the optimum moisture content. The optimum value of OPC was found to be 6%, at which the strength was the highest for both samples treated with OPC alone and samples treated with OPC and 20% recycled tiles. Under similar curing time, the strength of samples treated with recycled tiles and OPC was higher than the treated soil with the same percentage of OPC alone. The stress-strain curves showed ductile plastic behaviour for the untreated soft clay and brittle behaviour for almost all treated samples with OPC alone and OPC with recycled tiles. The microstructural tests indicated the formation of new cementitious products that were responsible for the improvement of the strength, such as calcium aluminium silicate hydrate. This research promotes recycled tiles as a green stabiliser for soil stabilisation capable of reducing the amount of OPC required for ground improvement. The replacement of OPC with recycled tiles resulted in higher strength compared to the control mix and this achievement may results in reducing both OPC in soil stabilisation and the disposal of recycled tiles into landfills.

Mechanical properties of tailings with dipping interlayers under high confining pressure

  • Qinglin, Chen;Zugui, Li;Zeyu, Dai;Xiaojun, Wang;Chao, Zhang
    • Geomechanics and Engineering
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    • 제31권6호
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    • pp.557-571
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    • 2022
  • Landslides are often triggered by weak interlayers initiated in tailings dam foundations, and hazards gradually occur. This is serious for landslides in high tailings dams due to their high potential energy. Tailing samples with a fine-grained interlayer at a set dip angle were prepared. Consolidated undrained (CU) triaxial shear tests were carried out by using a high-pressure triaxial apparatus. The results were compared with the results under a low confining pressure. Four reasons were summarized for high tailings dams more prone to instability than low dams. The shear strength of the samples with dipping interlayers decreases with increasing dip angle. An obvious straight drop in the stress path after the peak occurs in samples with dipping interlayers at an angle of 60°. The effect of the interlayer on the mechanical behaviour of tailings is very sensitive, especially for the sample with a dipping interlayer at an angle of 60°. Shear slipping along the interlayer should be given more attention in tailings dams. Compared with the results under low confining pressure, the stress decreases continuously for the samples with dipping interlayers at large angles under high confining pressure. The positive pore pressure, which reduces the effective stress, occurred in tailings samples under high confining pressure. The residual strength of tailings under high confining pressure is smaller than that under low confining pressure. These factors increase the dam break risk and the disaster impact for high tailings dams.

화학실험실의 휘발성유기화합물 노출에 대한 정량적 평가전략 (Quantitative Assessment Strategy for Determining the Exposures to Volatile Organic Chemicals in Chemistry Laboratories)

  • 변혜정;류경남;윤충식;박정임
    • 한국산업보건학회지
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    • 제21권1호
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    • pp.11-24
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    • 2011
  • Working in a research laboratory means exposure to a wide range of hazardous substances. Several studies indicated that laboratory workers, especially working with chemicals, might have an increased risk of certain cancers. However, exposure assessment data in laboratory settings are scarce. This study was performed to examine several approaches for quantitatively assessing the exposure levels to volatile organic compounds (VOCs) among workers in chemistry laboratories. The list of 10 target VOCs, including ethanol, acetone, 2-propanol, dichlormethane, tetrahydrofuran, benzene, toluene, n-hexane, ethyl acetate, chloroform, was determined through self-administered questionnaire for six chemistry research laboratories in a university, a government-funded research institute, or private labs. From September to December 2008, 84 air samples were collected (15 area samples, 27 personal time weighted samples, 42 personal task-basis short-term samples). Real time monitors with photo ionization detector were placed during the sampling periods. In this study, benzene was observed exceeding the action levels, although all the results were below the American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV). From the air sampling results, we concluded that (1) chemicals emitted during experiments could directly affect to neighbor office areas (2) chemical exposures in research laboratories showed a wide range of concentrations depending on research activities (3) area samples tended to underestimate the exposures relative to personal samples. Still, further investigation, is necessary for developing exposure assessment strategies specific to laboratories with unique exposure profiles.

방향족 유기화합물의 농도를 이용한 흡연자와 금연자의 호흡공기 조성 비교 (Comparison of breathing air samples between smoker and non-smoker by means of aromatic volatile organic compounds (VOC))

  • 김기현;임문순;최여진;홍윤정;이진홍
    • 분석과학
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    • 제18권5호
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    • pp.431-435
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    • 2005
  • 환경흡연 (Environmental Tobacco Smoking)의 폐해를 평가하기 위해, 금연을 결심한 사람들을 대상으로 정하여 주요 방향족 VOC 성분의 농도를 측정하였다. 금연 전후의 호흡시료를 확보하여, BTEX 성분의 농도를 관측하였다. 그 결과 호흡시료에 함유된 VOC는 금연 전과 후에 확연한 차이를 보이는 것으로 나타났다. 금연 전후 톨루엔 성분이 단일 성분으로 가장 높게 나타났다. 그러나 저감효과는 금연전 4.8에서 금연후 0.46 ppb 수준으로 줄어든 벤젠성분에서 가장 두드러지게 나타났다. 금연 후 시료의 농도는 비흡연자들의 호흡에서 발견되는 농도와 차이가 두드러지지 않았다. 전체적인 연구결과를 평가하였을 때, 본 연구에서 사용한 BTEX와 같은 성분들의 농도변화는 흡연과 금연의 단계를 평가하는 하나의 지표성분으로 활용가능하다는 것을 시사하였다.

알레르기 환자 가정에서 생물학적 유해인자에 대한 노출평가 -세균, 진균, 집먼지 진드기 알레르겐, 내독소를 대상으로 (Exposure Assessments on Biological Contaminants in Homes of Allergy Patients - Bacteria, Fungi, House Dust Mite Allergen and Endotoxin)

  • 문경환;변상훈;최달웅;김영환;이장희;이은실
    • 한국환경보건학회지
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    • 제31권2호
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    • pp.120-126
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    • 2005
  • To assess exposure of allergy patients to a biological environment, measurements were made of levels of airborne bacteria and fungi, house dust endotoxin and mite allergens in homes of 7 allergy patients and 12 healthy families. Concentrations of airborne total bacteria and the ratio of indoor and outdoor concentrations(I/O) in allergy patient's homes were high compared to non-allergy houses. But no significant differences could be shown for the concentration of spores of viable fungi and staphylococcus in indoor air between the homes of allergic patients and healthy families. The results of investigation on house dust mites, Dermatophagoids farinae were detected in all mattress samples and the levels in the allergy patient's homes were generally high, with individual measurements exceeding $2{\mu}g/g$ dust found in $30\%$ samples. In contrast with, Dermatophagoids pteronyssinus were detected in only $60\%$ samples and the concentrations were very low. The levels of endotoxin in dust samples collected from the allergy patient's home mattresses were higher than those of control houses. There was a positive correlation between the endotoxin levels and the house dust mite allergens.

Risk assessment of heavy metals in tuna from Japanese restaurants in the Republic of Korea

  • Seong-Jin Bae;Kyu-Sik Shin;Chulyong Park;Kiook Baek;So-Young Son;Joon Sakong
    • Annals of Occupational and Environmental Medicine
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    • 제35권
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    • pp.3.1-3.11
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    • 2023
  • Background: Studies on the risk of mercury (Hg) in Korean fishery products focus primarily on total Hg levels as opposed to methylmercury (MeHg) levels. None of the few studies on MeHg in tuna investigated tuna from Japanese restaurants. Few have evaluated lead (Pb), cadmium (Cd) and arsenic (As) in tuna. Thus, this study aimed to conduct a risk assessment by evaluating heavy metal concentrations in tuna from Japanese restaurants. Methods: Thirty-one tuna samples were collected from Japanese restaurants in the Republic of Korea. They were classified according to region and species. The concentration of heavy metals in the samples was analyzed using the Ministry of Food and Drug Safety Food Code method. The rate of exceedance of maximum residue levels (MRLs) and the risk compared to the provisional tolerable weekly intake (PTWI) set by the Joint Food and Agriculture Organization/World Health Organization Expert Committee on Food Additives (%PTWI) were evaluated for risk assessment. Results: The mean of MeHg, Pb, Cd and As concentrations were 0.56 ± 1.47 mg/kg, 33.95 ± 3.74 ㎍/kg, 14.25 ± 2.19 ㎍/kg and 1.46 ± 1.89 mg/kg, respectively. No sample exceeded the MRLs of Pb and Cd, but 9.7% of the samples exceeded the MRL of MeHg. The %PTWIs of MeHg, Pb, Cd and As were 4.2037, 0.0162, 0.0244 and 1.1627, respectively. The %PTWI of MeHg by age group and sex was highest among men aged 19-29 years (10.6494), followed by men aged 30-49 years (7.2458) and women aged 19-29 years (4.8307). Conclusions: We found that 3 out of 31 samples exceeded the MRL of MeHg. The %PTWI of MeHg showed significant differences based on age and sex, and the value was likely to exceed a safe level depending on individuals' eating behaviors. Therefore, improved risk management for MeHg is required.

Microbial contamination including Vibrio cholerae in fishery auction markets in West Sea, South Korea

  • Choi, Yukyung;Lee, Yewon;Lee, Soomin;Kim, Sejeong;Lee, Jeeyeon;Ha, Jimyeong;Oh, Hyemin;Shin, Il-Shik;Yoon, Yohan
    • Fisheries and Aquatic Sciences
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    • 제22권11호
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    • pp.26.1-26.7
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    • 2019
  • Background: The monitoring of pathogens of fishery auction markets is important to obtain safe fishery products regarding hygiene and sanitation. In this study, aerobic, coliform, Escherichia coli, and Vibrio cholerae were monitored in the fishery products and environmental samples obtained from fishery auction markets. Methods: The fishery products (flounder, octopus, skate, rock cod, sea bass, snail, monkfish, flatfish, comb pen shell, corb shell, conger eel, hairtail, croaker, and pilchard) were placed in filter bags, and the environmental samples (samples from the water tanks at the fishery auction markets, seawater from the fishery distribution vehicles, ice from wooden or plastic boxes, and surface samples from wooden and plastic boxes used for fish storage) were collected. Aerobic bacteria, E. coli, and coliform in the samples were enumerated on aerobic count plates and E. coli/coliform count plates, respectively. For V. cholerae O1 and V. cholerae non-O1 quantification, most probable number (MPN)-PCR analysis was performed. Results: Aerobic and coliform bacteria were detected in most samples, but E. coli was not detected. Wooden boxes were contaminated with high levels of aerobic and coliform bacteria in all seasons (spring, summer, and fall). During fall, V. cholerae non-O1 were detected in snails, hairtails, croakers, flatfishes, pilchards, plastic boxes, and water samples. Conclusions: These results indicate an increased prevalence of V. cholerae contamination in fishery products in fall, including food contact samples, which can be vehicles for cross-contamination.

대학 네일아트 실습 중 발생하는 휘발성 유기화합물의 공기 중 농도 평가 (Evaluation of Airborne Volatile Organic Compounds Concentrations During Nail Art Practicing for College Students)

  • 박윤경;최인자;최혜영;안재경;최상준;김수진;김현서
    • 한국산업보건학회지
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    • 제29권4호
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    • pp.452-463
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    • 2019
  • Objectives: The purpose of this study is to evaluate airborne concentrations of volatile organic compounds(VOCs) during nail art practice by college students. Methods: Personal samples for students were measured using passive samplers(OVM 3500) during three kinds of practice, including polish nail, gel nail and acrylic French sculpture at two universities located in Gyeongsangbuk-do Province. We also monitored area concentrations using active samplers and real-time total VOC monitors(ppbRAE 3000). All samples were analyzed with a gas chromatography flame ionized detector. Statistical analysis for monitored data were conducted using a web-based Bayesian toolkit, EXPOSTATS(www.expostats.ca). Results: Twenty-four personal samples and ten area samples were collected and five chemicals(acetone, butyl acetate, ethyl acetate, ethyl methacrylate(EMA) and methyl methacrylate(MMA)) were detected. Acetone was detected in all personal samples and ranged from 2.58 ppm to 50.3 ppm. EMA was detected in all personal and area samples with a maximum concentration of 9.78 ppm during acrylic French sculpture. Personal exposure levels to acetone, butyl acetate and mixtures were significantly higher with high occupant density (p<0.05). Geometric mean (GM) concentrations of 3.61 ppm for EMA personal samples were significantly higher than that of area samples, 1.5 ppm (p<0.05). Since there was no local ventilation, total VOC concentration continued to increase as the practice progressed. Conclusions: In order to minimize VOCs exposure for trainees, it is necessary to introduce a local ventilation system and maintain adequate occupant density.