• Title/Summary/Keyword: ppb level

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Quantitative analysis of ppb level VOCs by GC-AED (GC-AED에 의한 ppb 수준의 휘발성 유기화합물의 정량분석)

  • 문동민;김광섭;이진복;배현길;허귀석
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.04a
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    • pp.315-316
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    • 2000
  • 유해한 작업 환경지역, 공장밀집 지역 또는 주변 주거 지역의 대기에서 발생하는 악취성분 및 휘발성유기화합물은 환경규제 물질로 분류되고 국내적으로도 이들의 검출 및 정확한 정량적 분석을 위한 연구가 활발하게 진행되고 있다. 일반적으로 이들 성분들은 대기중에 미량으로 존재하기 때문에 흡착관 및 canister등에 의한 시료의 포집을 행하고 이들 분석시료를 실험실에서 저온농축과정을 거쳐 GC/FID 혹은 GC/MS등을 사용하여 정량분석을 실시한다. (중략)

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Study on Applying Artichoke Extract to Lessen The Toxicity of Aflatoxin to Chicken

  • Diep, Le Thi Ngoc
    • Toxicological Research
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    • v.17
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    • pp.281-287
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    • 2001
  • The Artichoke extract at 10% was used to add in drinking water to understand its effect on Aflatoxicosis of chickens. The Artichoke extract at the dose of 6 ml per liter of drinking water was given (experiment group) or not (control group) and to Hybro chickens (150 birds), during the first 49 days of life. Also, the chickens were fed with foodstuff containing 200 ppb or 500 ppb Aflatoxin $B_1$. Results showed that, the chickens having Artichoke extract: (1) Had overcome the growth retardation caused by the toxin at concentration of 200 ppb and 500 ppb of Aflatoxin $B_1$ (an addittonal weight gain of about 200-400 g/bird). (2) The feed conversion was improved (a reduction of 200-400 g of feed per kg of bird living weight). (3) Aflatoxicosis lesions were mild in the chickens, which fed 500 ppb of Aflatoxin $B_1$ or not found in those having the toxin 200 ppb. The blood examinations at 28th and 49th days of the trial gave the following results: (1) The Artichoke extract had an effect of suppressing the changes of blood cell numbers, hemoglobin amount. packed cell volume. leukocyte formula that were caused by Aflatoxin $B_1$. (2) The Artichoke extract had an effect of suppressing the diminution oj sugar, protein levels and the increase of the levels of GOT, GPT, alkaline phosphatase and bilirubin in the blood of intoxicated chickens. There was not or very Jew residue of Aflatoxin $B_1$ contained in the liver and muscle of chickens intoxicated by Aflatoxin $B_1$ having Artichoke, that was much lower than the allowed level in animal products.

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Scenario Analysis of Personal Nitrogen Dioxide Exposure with Monte Carlo Simulation on Subway Station Workers in Seoul (확률론적 모의실험 기법을 이용한 일부 지하철 근무자들의 이산화질소 개인노출 시나리오 분석)

  • 손부순;장봉기;양원호
    • Journal of Environmental Science International
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    • v.10 no.3
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    • pp.195-200
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    • 2001
  • The personal exposures of nitrogen dioxide(NO$_2$), microenvironmental levels and daily time activity patterns on Seoul subway station workers were measured from February 10 to March 12, 1999. Personal NO$_2$exposure for 24 hours were 29.40$\pm$9.75 ppb. NO$_2$level of occupational environment were 27.87$\pm$7.15 ppb in office, 33.60$\pm$8.64 ppb in platform and 50.13$\pm$13.04 ppb in outdoor. Personal exposure time of subway station workers was constituted as survey results with $7.94\pm$3.00 hours in office, $2.82\pm$1.63 hours in platform and 1 hours in outdoor. With above results, personal $NO_2$exposure distributions on subway station workers in Seoul were estimated with Monte Carlo simulation which uses statistical probabilistic theory on various exposure scenario testing. Some of distributions which did not have any formal patterns were assumed as custom distribution type. Estimated personal occupational $NO_2$exposure using time weighted average (TWA) model was 31.$29\pm$5.57 ppb, which were under Annual Ambient Standard (50ppb) of Korea. Though arithmetic means of measured personal $NO_2$exposure was lower than that of occupational $NO_2$exposure estimated by TWA model, considering probability distribution type simulated, probability distribution of measured personal $NO_2$exposures for 24 hours was over ambient standard with 3.23%, which was higher than those of occupational exposure(0.02%). Further research is needed for reducing these 24 hour $NO_2$personal excess exposures besides occupational exposure on subway station workers in Seoul.

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Air Quality Prediction by CDMQC and Its Validation in the Ulsan Industrial Complex (CDMQC Model을 이용(利用)한 울산지역(蔚山地域)의 대기질(大氣質) 예측(豫測)과 실측치(實測値)와의 비교연구(比較研究))

  • Shin, Eung Bai;Lee, Kwang Ho
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.1 no.1
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    • pp.77-90
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    • 1981
  • This study involves 1) air quality disperson predictions and 2) a comparison of the predicted data with the actually measured ones in terms of annual sulfur dioxide concentration in the Ulsan Industial Complex. The prediction was made by utilizing the CDMQC air quality simulation computer model. The higher concentrations were observed at the Bugok Dong (Sampling Site) and the Yeochun Dong Sampling Site with the values of 44 and 46 ppb, respectively whereas the predicted values for both sites were 52 and 47 ppb, respectively. A statistical examination has revealed that the level of confidence was 90.02% from the Chi-squared test and the corelation coefficient was 0.827. It thus demonstrates that the model used for the study appears to be applicable to yield reliable predictions in terms of annual sulfur dioxide concentrations in the study area.

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Monitoring of Aluminium Phosphide Residues in Wheat and Wheat Flour (밀과 밀가루 중 알루미늄포스파이드 잔류량 모니터링)

  • Choi, Yong-Hoon;Yoon, Sang-Hyeon;Hong, Hye-Mi;Kang, Yun-Sook;Chae, Kab-Ryong;Lee, Jong-Ok
    • Korean Journal of Food Science and Technology
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    • v.37 no.4
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    • pp.532-536
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    • 2005
  • GC-NPD analysis was performed on residues of aluminium phosphide in raw wheat and wheat products by trapping gaseous phosphine in the headspace of vessel. In Australian wheat, over 95% of samples were detected below 1 ppb, considered as safe level, whereas in American wheat, about 70% of 58 samples were detected within 1-10 ppb with 4 showing over 10 ppb. About 14-22% phosphine residues of raw wheat were retained after milling process. Wheat samples of same origin showed significant varying levels of phosphine.

Detection of Aflatoxins in Some Korean Foodstuffs (몇가지 한국식품(韓國食品)중 Aflatoxin의 검출(檢出))

  • Kim, Yong-Hwa;Hwangbo, Jeong-Sook;Lee, Su-Rae
    • Korean Journal of Food Science and Technology
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    • v.9 no.1
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    • pp.73-80
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    • 1977
  • In order to detect the occurrence of aflatoxins in some suspecious Korean foodstuffs, 54 samples of Meju (a naturally inoculated soybean substrate for soy sauce and paste fermentation), 125 samples of Doenjang (a Korean-style fermented soybean paste), both produced at household level, and 31 samples of peanut were collected from 8 major cities of South Korea and subjected to assay by the official method of AOAC. The results were as follows: 1) Frequencies for the occurrence of aflatoxins in Meju, Doenjang and peanut were 7.4%(4/54), 8.8%(11/125) and none (0/31), respectively, in which Meju and Doenjang samples from Daegu and Busan showed the high ratio of the presence. 2) A Doenjang sample from Busan was found to contain the highest content of aflatoxins, of which $B_1,\;B_2,\;G_1\;and\;G_2$ were 66 ppb, 13 ppb, non-detectable and 5 ppb, respectively, while other samples detected were for $G_2$ only. 3) The identity of aflatoxin $B_1$ isolated from the Doenjang sample from Busan was confirmed by thin-layer chromatographic behavior, derivative formation and chicken embryo bioassay.

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Safety and Risk Assessment of Arsenic in Drinking Water (음용수를 통한 비소 노출의 인체 안전성 평가)

  • 이무열;정진호
    • Toxicological Research
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    • v.18 no.2
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    • pp.107-116
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    • 2002
  • Arsenic (As) is a ubiquitous element found in several forms in foods and water. Although certain foods, such as marine fish, contain substantial levels of organic arsenic forms, they are relatively low in toxicity compared to inorganic forms. in contrast, arsenic in drinking water is predominantly inorganic and highly toxic. Chronic ingestion of arsenic-contaminated drinking water is therefore the major pathway posing potential risk to human hearth. since the early 1990s in Bangladesh ozone, arsenic exposure has caused more than 7,000 deaths and uncounted thousands shout symptoms of long-term arsenic poisoning. Significant portion of world populations are exposed to low to moderate levels of arsenic of parts per billion (ppb) to hundreds of ppb. As a consequence, the World Health Organization (WHO) and U.S. environmental health agencies, such as the Environmental Protection Agency (EPA) made arsenic their highest priority. Recently, the WHO, European Union (EU), and US. EPA lowered an acceptable level of 10 ppb for arsenic in drinking water In this article, various health effects of arsenic in drinking water were reviewed and the current status for risk assessment to regulate arsenic in drinking water was discussed.

Fermentation Specific Carcinogen Ethyl Carbamate in Korean Traditional Foods (한국 전통 발효식품 중의 Ethyl Carbamate 정량)

  • 정현정;권훈정
    • Journal of the East Asian Society of Dietary Life
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    • v.7 no.1
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    • pp.41-46
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    • 1997
  • Diet is generally accepted as one of the important factors in human cancer development. Ethyl carbamate has been associated with cancer for several decades and mainly found in the fermented beverages and foodstuff. The relationship between ethyl carbamate and the human health cannot be ignored especially in the areas where fermented foods consists of regular food consumption. To investigate the ethyl carbamate exposure level in Korean population, commercial fermented food samples were collected form local markets I Seoul area and home-made varieties were collected throughout the country. Following partial purification the concentration of ethyl carbamete was determined by GC/ MS. The concentration of ethyl carbamate ranged to 70 ppb in soysauce, to 10 ppb in soybean paste, and to 5 ppb in vinegars. Korean traditional alcoholic beverages showed small amount of ethyl carbamate. The estimated daily exposure of Korean population was 0~1900ng/day. It would be prudent to put efforts to minimize the formation of ethyl carbamate since the risk from the higher range exposure cannot be ignored.

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Clinical Features of Chronic Obstructive Pulmonary Disease with High Fractional Exhaled Nitric Oxide

  • Ahn, Seong;Kim, Tae-Ok;Chang, Jinsun;Shin, Hong-Joon;Kwon, Yong-Soo;Lim, Sung-Chul;Kim, Yu-Il
    • Tuberculosis and Respiratory Diseases
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    • v.83 no.3
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    • pp.234-241
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    • 2020
  • Background: The fractional exhaled nitric oxide (FENO) test is useful in asthma patients. However, a few studies on its usefulness in chronic obstructive pulmonary disease (COPD) patients have been reported. We analyzed the FENO level distribution and clinical characteristics according to the FENO level in COPD patients. Methods: From December 2014 to June 2019, COPD patients who underwent pulmonary function and FENO tests at Chonnam National University Hospital were retrospectively evaluated for FENO, comorbidities, asthma history, blood eosinophil, and pulmonary function test. The high FENO group was defined as those with FENO level>25 parts per billion (ppb). Results: A total of 849 COPD patients (mean age, 70.3±9.4 years) were included. The mean forced expiratory volume at 1 second was 66.5±21.7% and the mean FENO level was 24.3±20.5 ppb. Patients with FENO ≤25 ppb were 572 (67.4%) and those with FENO >25 ppb were 277 (32.6%). Blood eosinophil percentage was significantly higher (4.2±4.8 vs. 2.7±2.5, p<0.001) in patients with the high FENO group than the low FENO group. The high FENO group revealed a significantly higher frequency of patients with blood eosinophil percentage >3% (46.9% vs. 34.8%, p=0.001) and asthma history (25.6% vs. 8.6%, p<0.001) than the lower FENO group. Asthma history, blood eosinophil percentage >3%, and positive bronchodilator response (BDR) were independent risk factors for the high FENO level (adjusted odds ratio [aOR], 3.85; p<0.001; aOR, 1.46; p=0.017; and aOR, 1.57, p=0.034, respectively) in the multivariable analysis. Conclusion: The FENO level distribution varied in COPD patients and the mean FENO value was slightly elevated. Asthma history, eosinophil percent, and positive BDR were independent risk factors for the high FENO level.