• 제목/요약/키워드: toxic

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Presence of benthic dinoflagellates around coastal waters of Jeju Island including newly recorded species

  • Shah, Md. Mahfuzur Rahman;An, So-Jung;Lee, Joon-Baek
    • Journal of Ecology and Environment
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    • 제36권4호
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    • pp.347-370
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    • 2013
  • A study on the presence of benthic dinoflagellates in the intertidal zone along the coasts of Jeju Island, Korea was conducted during 2011 and 2012. Identification and taxonomic observations were made of the benthic dinoflagellate samples using light and epifluorescence microscopy. Thirty-seven dinoflagellate taxa belong to five orders, nine families, 18 genera and 30 species, which are new records for Korean waters, were detected in this study. The detailed nomenclature, references, distribution, and illustrations are presented here. The commonly occurring genera were Amphidinium, Coolia, Ostreopsis, Prorocentrum, and Thecadinium. Among the recorded species, 26 were found only in sand sediment, seven in macroalgal samples, and four were found in both sand and macroalgal samples. Of the 37 species, nine were potentially toxic. These results suggest that diversified benthic dinoflagellates including several potentially toxic species occur in sand sediment and macroalgae in the intertidal zone along the coasts of Jeju Island. The morphological features of the identified species were more or less similar to observations made by previous studies in Korea and elsewhere. The presence of known toxic species may indicate a potential risk of toxicity in the marine ecosystem of Jeju Island. The present study can be helpful for further detailed taxonomic, toxicological, molecular phylogenetic studies and may help in the management and conservation of Jeju Island's marine ecosystem.

폐타이어 건류 소각에서 발생되는 재와 배기 가스에서의 독성 오염 물질의 정량 (Characterization of Toxic Pollutants in Ash and Flue Gas from Gasification Incinerator of Waste Tires)

  • 구자공;서영화;김석완;유동준
    • 대한토목학회논문집
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    • 제13권1호
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    • pp.213-220
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    • 1993
  • 본 논문에서는 해마다 수 십만 개씩 발생되는 폐타이어의 열적 처리 방법인 건류 소각 처리 방법에서 발생되는 이차 오염 물질을 정량하여 폐타이어의 안전한 최종 처리 방법까지 고찰하였다. 건류-소각처리 방법에서 발생되는 배기 가스에서 이차 독성 오염 물질을 화학 평형 모델을 응용하여 예측하였고 실질적인 잔류 물질인 건류재와 소각재에서 유기성 독성 물질과 중금속을 정량하였다. 건류재에서는 폐타이어의 불완전 연소에 따른 유기성 이차 오염 물질이 다량 포함되어 있는 반면에 소각재에서는 납과 카드뮴과 같은 중금속 화합물의 함량이 높았다. 건류재 및 소각재의 안전한 최종 매립을 위하여는 서로 다른 전처리 방법이 요구된다.

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일부 중금속과 제초제에 대한 저서규조류 Nitzschia sp.의 광합성 반응 (Photosynthetic Responses of the Benthic Diatom Nitzschia sp. to Selected Heavy Metals and Herbicides)

  • 강은주;최태섭;김광용
    • ALGAE
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    • 제22권4호
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    • pp.319-323
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    • 2007
  • This study was conducted with using chlorophyll a fluorescence (indicated as photosynthetic activity) to examine the toxic effect of 96 h exposure of heavy metals and herbicides on the benthic diatom Nitzschia sp. which was isolated from pristine sediment in Pamquat Harbour, Nova Scotia, Canada. Samples of benthic diatom were exposed to 0, 0.01, 0.1 and 1 mg L–1 of copper, 0, 1, 10 and 100 mg L–1 of chrome (VI), 0, 2.45, 24.5 and 245 mg L–1 of paraquat dichloride, and 0, 4.37, 43.7 and 437 mg L–1 of alachlor during 96 hours. The effective quantum yield of photochemistry (ΔF/Fm’) was evaluated by subjecting light acclimated samples to saturating pulses of light using a pulse amplitude modulated (PAM) fluorometer. The impact of heavy metals on Nitzschia sp. photosynthesis was not severe in < 1 mg L–1 but in the high concentrations (> 1 mg L–1) clearly increased toxic stress during 96 h. Herbicides had a limited impact during the exposure period but clearly increased stress on the benthic diatom with increasing concentrations. Acute response of Nitzschia sp. to selected heavy metals and herbicides was characterized, and the capacity of a benthic diatom to tolerate and recover from toxic stress was assessed.

영월지역 토양중 PFA로부터 기인된 잠재적 독성원소의 분포 (The Distribution of Potentially Toxic Elements in Soils Derived from PFA near Youngwol Power Plant)

  • 최선경;문희수;송윤구;유장한
    • 자원환경지질
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    • 제31권6호
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    • pp.509-518
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    • 1998
  • Fly ashes have been deposited around Youngwol power plant until electrostatic precipitator was installed in 1981. Fresh fly ash samples from electrostatic precipitator and weathered fly ash from ash disposal site were collected from Youngwol power plant, along with 65 soil samples of nearby area to look into the influence of PFA deposit on the soils in surrounding area. In chemistry, EPA does not contain high level of toxic elements and there is no notable concentration of toxic elements in soil near power plant. Total concentrations of Co, Cr, Cu, V, and Zn are 13 ppm, 89 ppm, 73 ppm, 157 ppm and 57 ppm in PFA. Concentrations of theses elements in ash-rich soils are 15 ppm, 78 ppm, 60 ppm, 133 ppm and 68 ppm, and those in ash-poor soils are 19 ppm, 70 ppm, 38 ppm, 91 ppm and 97 ppm. But these metal elements are highly concentrated in magnetic fractions of EPA (Co, 129 ppm; Cr, 217 ppm; Cu, 210 ppm; V, 197 ppm; Zn 90 ppm). Considering the process of long-term weathering of PFA, potentially toxic substances from the ash could be leached into soils and groundwater.

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다중이용시설 바닥마감재의 연소가스 독성평가에 관한 실험 연구 (The Experimental Study on the Toxic Gases Released from the Floor Finishing Materials in Entertainment Service Industry Buildings)

  • 강성동;이창우;현성호;윤명오
    • 한국화재소방학회논문지
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    • 제16권2호
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    • pp.14-21
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    • 2002
  • 다중이용시설에서 많이 사용중인 바닥마감재를 대상으로 연소가스의 독성을 NES 713의 방법에 의해 평가하였다. 또한, 공기가 공급되지 않는 밀폐된 공간에서의 연소시 각 시료에 따라 발생할 수 있는 유독성가스를 가스분석기를 이용하여 시간변화에 따라 연속적으로 측정하여 비교·분석함으로서 화재 시 내포하고 있는 바닥마감재의 위험성을 평가하였다. NES 713 방법에 의한 각 제품의 유독가스의 독성지수를 살펴본 결과 2~9.7의 값을 갖고 있으며, 화재시 유독가스에 의한 매우 큰 위험성을 내포하고 있다.

화학장치설비의 유해독성가스 누출에 대한 분산모델링 방법론 (Dispersion Modeling Methodology for Hazardous/Toxic Gas Releases from Chemical Plant Facilities)

  • 송덕만
    • 한국가스학회지
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    • 제1권1호
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    • pp.73-80
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    • 1997
  • 본 연구는 화학장치설비중 저장탱크에서 누출된 유해독성가스인 염소의 풍하거리에 따른 10분 평균, 30분 평균 및 1시간 평균 최대 지표면 농도를 산출하여 염소가스의 법적 규제농도인 IDLH 및 ERPG-3 농도들과 비교함으로써 유해위험거리 (hazard distance) 또는 독성완충거리 (toxic buffer distance)를 정량적으로 예측하는 분산모델링 방법론을 개발하고자 수행되었다. 본 분산모델링을 위하여 누출원모델, 분산모델, 기상 및 지형자료들 이 SuperChems 모델에 입력자료로 사용되었으며, 대기의 안정도, 풍속, 표면거칠기 길이의 변화에 따른 지표면 농도의 영향이 평가되었다.

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독성대사체를 생성하는 다빈도사용 한약재의 안전성등급화 - 천궁, 당귀, 감초, 숙지황을 중심으로 - (Safety classification for frequently-used herbal medicines inducing toxic metabolites)

  • 박영철;이선동
    • 대한예방한의학회지
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    • 제19권2호
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    • pp.123-133
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    • 2015
  • The new formular for herbal medicine-safety classification in terms of evidence-based medicine was developed and applied to evaluate various herbal medicines in the previous study. This study is aimed to evaluate the frequently-used herbal medicines inducing toxic metabolites or reactive intermediates(RI), such as Ligusticum wallichii Franch, Angelica sinensis, Glycyrrhizae Radix, Rehmanniae Radix, based on 6 safety grades calculated from human equivalent dose(HED)-based MOS(margin of safety). HED-based MOS can be explained as the ratio of theoretical ALD(approximate lethal dose) of human as $LD_1$(lethal dose of 1%)/ clinical maximum dose as $ED_{99}$(Effective dose of 99%). The herbal medicine showing the ratio less than 1 belongs to Class 1, but the herbal medicine showing the ratio more than 500 belongs to Class 6 with the lowest toxicity. As a result, they were evaluated as class 2 for Angelica sinensis and Glycyrrhizae Radix, class 3 for Ligusticum wallichii Franch and Rehmanniae Radix. These resultant grades for 4 herbal medicines were lower than the grade expected under consideration that these herbal medicines are used very frequently in oriental clinics. These low grades would be due to their ingredients which is biotransformed to toxic metabolites.

Necrotizing fasciitis and streptococcal toxic shock syndrome secondary to varicella in a healthy child

  • Kwak, Byung Ok;Lee, Min Jung;Park, Hye Won;Song, Min Kyung;Chung, Sochung;Kim, Kyo Sun
    • Clinical and Experimental Pediatrics
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    • 제57권12호
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    • pp.538-541
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    • 2014
  • Varicella is usually considered to be a benign disease in healthy children; however, serious complications can occur such as necrotizing fasciitis and toxic shock syndrome. We describe a 38-month-old girl with necrotizing fasciitis and streptococcal toxic shock syndrome following varicella. She was previously healthy and vaccinated against varicella at 12 months of age. She had been diagnosed with varicella three days prior to presenting at our facility; she developed fever, vomiting, and painful swelling on her left flank. Her skin lesions worsened, she became lethargic, and had episodes of hypotension and coagulopathy. Necrotizing fasciitis on the left abdominal wall, buttocks, and left thigh was diagnosed by magnetic resonance imaging, and group A Streptococcus was isolated from a tissue culture. She was diagnosed as necrotizing fasciitis and streptococcal toxic shock syndrome, and successfully treated with repeated surgical debridement and fasciotomy, in addition to intensive antibiotics. Our experience suggests that necrotizing fasciitis in patients with varicella should be considered to be a rare complication even with widespread vaccine use. Early diagnosis and intensive treatment are required to prevent a fatal outcome.

Bacterial Community Composition of Activated Sludge Relative to Type and Efficiency of Municipal Wastewater Treatment Plants

  • Ahn, In-Sook;Kim, Myeong-Woon;La, Hyun-Joon;Choi, Kyung-Min;Kwon, Joong-Cheon
    • Journal of Microbiology and Biotechnology
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    • 제13권1호
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    • pp.15-21
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    • 2003
  • Two microbial communities of activated sludge in the same municipal wastewater, but treated with different systems, were studied and compared using molecular microbiological approaches. The bacterial 16S rDNA sequences from 124 clones were analyzed, however, the majority of them were not closely related to any known species, and found to belong to 8 different phylogenetic groups and 3 different unidentified groups. The relative frequencies of each group were similar between the two microbial communities. Fingerprinting using terminal restriction fragment length polymorphism (T-RFLP) showed that the putative Nitrospira-related populations were more diverse and quantitatively higher in the KNR process system than in the other system using a conventional activated sludge process. The relationship between the bacterial community composition and the higher removal efficiency of nitrogen and phosphorus in the KNR process is discussed.

Characteristics of Six New Bacillus thuringiensis Serovarieties: B. thuringiensis serovar. coreanensis, leesis, konkukian, seoulensis, sooncheon, and yosoo

  • Lee, Kwang-Yong;Kwon, Hyuk-Han;Kang, Eun-Young;Lee, Min-Jung;Kim, Eui-Na;Chu, Dong-Wan;Park, Soo-Il;Ngo, Din-Binh;Lee, Hyung-Hoan
    • Journal of Microbiology and Biotechnology
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    • 제14권3호
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    • pp.509-514
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    • 2004
  • Six new serovarieties of B. thuringiensis carrying specific H-antigen have minor differences in biochemical characteristics and morphological characteristics of crystals, which are commonly resistant against four antibiotics. The B. thuringiensis serovar. coreanensis is nontoxic to silkworm larvae, but it is moderately toxic against the Culex pipiens larvae. The B. thuringiensis serovar. konkukian and leesis are nontoxic against mosquitos larvae, but are toxic against silkworm larvae. The B. thuringiensis serovar. seoulensis, sooncheon, and yosoo are highly toxic to B. mori larvae and moderately toxic to C. pipiens larvae. The six serovarieties harbor different plasmid DNA patterns. A 102-kDa protein is a major crystal protein in the four serovarieties and a 86-kDa protein is in one serovariety.