• Title/Summary/Keyword: Low exposure

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Dietary Risk Assessment for Polycyclic Aromatic Hydrocarbons in Foods (식품중 Polycyclic Aromatic Hydrocarbons의 위해성평가)

  • 이효민;윤은경;박경아;김윤희;정소영;권기성;김명철;송인상;이철호
    • Journal of Food Hygiene and Safety
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    • v.19 no.1
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    • pp.1-8
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    • 2004
  • This study was executed to determine the cumulative dietary risk of PAHs exposed by food ingestion. Food samples including barbecued beef, barbecued pork, grilled chicken, ham, bacon and vegetable oil which were collected from food markets. These samples were saponified, extracted and cleaned up to purify PAHs, and then the purified sample solutions were analyzed by HPLC-FL. Generally, the levels of total PAHs in barbecued beef (0.2 ppb), bacon (0.3 ppb), barbecued pork (0.7 ppb), ham (0.8 ppb), and vegetable oil (1.2 ppb) were low, whereas the level of total PAHs in grilled chicken (9.3 ppb) was significantly high. For the exposure assessment of PAHs due to food ingestion, PAHs levels converted into TEQ$_{BaP}$, the average body weight for 20-73 age group and consumed levels of food proposed from report on the National Health and Nutrition Survey were used. The estimated lifetime average daily intake of dietary PAHs was 4.32${\times}$10$^{-4}$ $\mu\textrm{g}$-TEQ$_{BaP}$kg/day as the mean value. The dietary risk adjusted to cancer potency of benzo(a)pyrene as 7.3 (mg/kg/day)$^{-1}$ was 3.44${\times}$10$^{-6}$ based on current data.ata.

Risk Ranking Analysis for the City-Gas Pipelines in the Underground Laying Facilities (지하매설물 중 도시가스 지하배관에 대한 위험성 서열화 분석)

  • Ko, Jae-Sun;Kim, Hyo
    • Fire Science and Engineering
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    • v.18 no.1
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    • pp.54-66
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    • 2004
  • In this article, we are to suggest the hazard-assessing method for the underground pipelines, and find out the pipeline-maintenance schemes of high efficiency in cost. Three kinds of methods are applied in order to refer to the approaching methods of listing the hazards for the underground pipelines: the first is RBI(Risk Based Inspection), which firstly assess the effect of the neighboring population, the dimension, thickness of pipe, and working time. It enables us to estimate quantitatively the risk exposure. The second is the scoring system which is based on the environmental factors of the buried pipelines. Last we quantify the frequency of the releases using the present THOMAS' theory. In this work, as a result of assessing the hazard of it using SPC scheme, the hazard score related to how the gas pipelines erodes indicate the numbers from 30 to 70, which means that the assessing criteria define well the relative hazards of actual pipelines. Therefore. even if one pipeline region is relatively low score, it can have the high frequency of leakage due to its longer length. The acceptable limit of the release frequency of pipeline shows 2.50E-2 to 1.00E-l/yr, from which we must take the appropriate actions to have the consequence to be less than the acceptable region. The prediction of total frequency using regression analysis shows the limit operating time of pipeline is the range of 11 to 13 years, which is well consistent with that of the actual pipeline. Concludingly, the hazard-listing scheme suggested in this research will be very effectively applied to maintaining the underground pipelines.

Effect of Antler Velvet Ethanol Extract on Common Serum Chemistry Panels and Histopathological Change in Rats Exposed to 2,3,7,8-Tetrachlorodibenzo-p-dioxin (녹용 에탄올 추출물이 2,3,7,8 Tetrachlorodibenzo-p-dioxin에 노출된 랫드의 일반 혈액 화학 지수 및 조직 병변에 미치는 효과)

  • Choi, Kyung-Yun;Hwang, Seock-Yeon;Lee, Su-Chan;Kim, Si-Kwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.35 no.9
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    • pp.1178-1184
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    • 2006
  • This study was carried out to investigate the effect of ethanol extract of antler velvet (EAV) on common serum chemistry panels and histopathological change in rats exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). Administration of TCDD ($50{\mu}g/kg$ body weight) induced significant decrease in platelet count (p<0.01), creatine phosphokinase (CPK, p<0.01), lactatate dehydrogenase (LDH, p<0.05) and glucose (p<0.05) levels and increase in hemoglobin (p<0.05), aspartate aminotransferase (AST, p<0.01), alanine amino transferase (ALT, p<0.05) and lipase activities (p<0.05), and blood urea nitrogen (BUN, p<0.05), triglyceride (p<0.01) and low density lipoptotein cholesterol (LDL-C, p<0.05) levels. However, pretreatment of EAV at daily dose of 20 mg/kg b.w. from 1 wk before TCDD exposure for 5 wks attenuated the abnormality of the overall serum chemistry panels but statistical difference between TE and TA groups was observed only in testicular weight (p<0.01), LDH activity (p<0.05), glucose (p<0.05) and lipase activity (p<0.01). In addition, TCDD induced significant histopathological changes including swelling, fatty metamorphosis, and vacuolar degeneration in liver; edema in proximal and distal convoluted tubules, and glomerulus in kidney; severe atrophy of red purple and appearance of significant number of macrophage in spleen; prominent atrophy and decrease in immune cells in thymus. On the other hand, administration of EAV attenuated histopathological damage induced by TCDD. These results further suggest that administration of EAV attenuates TCDD induced testicular, liver, pancreatic, hematopoietic and nephrotic toxicities in rats.

Application of Chlorophyll Fluorescence Parameters for the Detection of Water Stress Ranges in Grafted Watermelon Seedlings (수박접목묘의 건조스트레스 범위 탐지를 위한 엽록소형광 지수의 적용)

  • Shin, Yu Kyeong;Kim, Yong Hyeon;Lee, Jun Gu
    • Journal of Bio-Environment Control
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    • v.28 no.4
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    • pp.461-470
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    • 2019
  • This study was carried out to quantify the drought stress in grafted watermelon seedlings non-destructively by using chlorophyll fluorescence (CF) imaging technique rather than the visual judgment. Six-day old watermelon seedlings were grown under uniform irrigation for 3 days, and then given drought stress. Afterward, the sensor for the measurement of water content in plug tray cell unit was used to classify the drought-stress level into nine groups from D1 (53.0%, sufficient moisture state) to D9 (15.7%, extremely dry stress), and the 16 CF parameters were measured. In addition, re-irrigation was performed on the drought stressed seedlings(D5 - D9) to determine the growth and photosynthesis recovery level, which was not confirmed by visual judgment. The kinetic curve patterns of CF in three different drought stressed seedling groups were found to be different for the early detection of drought stress. All the 16 CF parameters decreased continuously with exposure to drought stress and drastically decreased from D5 (32.1%) where the visual judgment was possible. The fluorescence decline ratio (Rfd_Lss) started to decrease from the initial drought stress level (D5 - D6), and the Maximum PSII quantum yield (Fv/Fm) was significantly decreased in the later extreme drought stress range (D7 - D9) by re-irrigation recovery test. Thus, Rfd_Lss and Fv/Fm parameters were finally selected as potent indicators of growth and photosynthesis recovery in the initial and later stages of drought stress. Also, to the differences in the numerical values of the individual chlorophyll fluorescence parameters, the drought stress level was intuitively confirmed through the image. These results indicate that Rfd and Fv/Fm can be considered as potential CF parameters for the detection of low and extremely high drought stress, respectively. Furthermore, Fv/Fm can be considered as the best CF parameters for recovery at re-irrigation.

Effect of Packaging Systems with High CO2 Treatment on the Quality Changes of Fig (Ficus carica L) during Storage (저장 중 무화과(Ficus carica L) 선도유지를 위한 고농도 이산화탄소 처리된 포장 시스템 적용 연구)

  • Kim, Jung-Soo;Chung, Dae-Sung;Lee, Youn Suk
    • Food Science and Preservation
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    • v.19 no.6
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    • pp.799-806
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    • 2012
  • This experiment was conducted to establish the optimum conditions for high $CO_2$ gas treatment in combination with a proper gas-permeable packaging film to maintain the quality of fig fruit (Ficus carica L). Among the fig fruits with different high $CO_2$ treatments, the quality change was most effectively controlled during storage in the 70%-$CO_2$-treated fig fruit. Harvested fig fruit was packaged using microperforated oriented polypropylene (MP) film to maintain the optimum gas concentrations in the headspace of packaging for the modified-atmosphere system. MP film had an oxygen transmission rate of about $10,295cm^3/m^2$/day/atm at $25^{\circ}C$. The weight loss, firmness, soluble-solid content (SSC), acidity (pH), skin color (Hunter L, a, b), and decay ratio of the fig fruits were monitored during storage at 5 and $25^{\circ}C$. The results of this study showed that the OPP film, OPP film + 70% $CO_2$, and MP film+70% $CO_2$ were highly effective in reducing the loss rate, firmness and decay occurrence rate of fig fruits that were packaged with them during storage. In the case of using treatments with packages of OPP film and OPP film+70% $CO_2$, however, adverse effects like package bursting or physiological injury of the fig may occur due to the gas pressure or long exposure to $CO_2$. Therefore, the results indicated that MP film containing 70% $CO_2$ can be used as an effective treatment to extend the freshness of fig fruits for storage at a proper low temperature.

Effect of Physical Control Technology on Aspergillus ochraceus Reduction (물리적 제어기술이 Aspergillus ochraceus 저감화에 미치는 영향)

  • Lee, Eun-Seon;Kim, Jong-Hui;Kim, Bu-Min;Oh, Mi-Hwa
    • Journal of Food Hygiene and Safety
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    • v.36 no.5
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    • pp.447-453
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    • 2021
  • In this study, the effectiveness of physical control technology, a combined light sterilization (LED, UV) and hot water treatment in reducing Aspergillus ochraceus for food production environment was investigated. In brief, 1 mL aliquot of A. ochraceus spore suspension (107-8 spore/mL) was inoculated onto stainless steel chips, which was then dried at 37℃, and each was subjected to different physical treatment. Treatments were performed for 0.5, 1, 2, 5, 8, and 11 hours to reduce the strains using a light-emitting diode, but no significant difference was confirmed among the treatments. However, a significant reduction was observed on the chips treated with UV-C exposure and hot water immersion. After being treated solely with 360 kJ/m2 of UV-C on stainless steel chip, the fungi were significantly reduced to 1.27 log CFU/cm2. Concerning the hot water treatment, the initial inoculum amount of 6.49 log CFU/cm2 was entirely killed by immersion in 83℃ water for 5 minutes. Maintaining a high temperature for 5 minutes at the site is difficult. Thus, considering economic feasibility and usability, we attempted to confirm the appropriate A. ochraceus reduction conditions by combining a relatively low temperature of 60℃ and UV rays. With the combined treatments, even in lukewarm water, A. ochraceus decreased significantly through the increases in the immersion time and the amount of UV-C irradiation, and the yield was below the detection limit. Based on these results, if work tools are immersed in 60℃ lukewarm water for 3 minutes and then placed in a UV sterilization device for more than 10 minutes, the possibility of A. ochraceus cross-contamination during work is expected to be reduced.

Growth and Blood Characteristics of Red Sea Bream Pagrus major by Starvation and Stocking Density during Red Tide (적조발생시기 참돔의 절식과 사육밀도에 따른 성장과 혈액성상)

  • Kim, Won-Jin;Lee, Jeong-Yong;Shin, Yun-Kyung;Won, Kyoung-Mi
    • Korean Journal of Ichthyology
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    • v.30 no.4
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    • pp.194-204
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    • 2018
  • In order to minimize the damage on the red sea bream Pagrus major by a harmful dinoflagellate Cochlodinium polykrikoides, we investigated the effect of feeding, starvation and stocking density on the survival rate, growth, growth restoration and physiological response of P. major exposure to C. polykrikoides. The experimental groups were divided into three groups such as F-HD (feeding and high density with $6.4kg/m^3$), S-HD (starvation and high density with $6.4kg/m^3$) and S-LD (starvation and low density with $3.2kg/m^3$) according to stocking density and starvation in marine cage ($11m{\times}11m{\times}5m$). The F-HD was fed throughout the experiment for 9 weeks, whereas S-HD and S-LD were not fed for 5 weeks and then refeeding for 4 weeks. Survival rate was the lowest in F-HD (85.5%) and S-LD was the highest (97.3%). The growth rates of S-HD and S-LD were significantly lower than F-HD during starvation period for 4 weeks, but rapidly recovered after feeding. The nutritional status such as ALB, TP, TCH, TG were similar to tendency of growth data. Ht, Hb, AST, ALT and GLU levels were significantly higher in the F-HD than in the starvation groups at the same time (in 3 week) during starvation period. But starvation groups did not differ during starvation period. As a result, F-HD is more sensitive to stress than S-HD and S-LD. Thus, during C. polykrikoides bloom period, starvation and stocking density control can help survival and growth restoration of the red sea bream.

Use of mothers' home meal replacement and diet quality of their young children (유아 어머니의 유아식사에서 가정간편식 이용 빈도에 따른 유아 자녀의 식사의 질 평가)

  • Kim, Bo-Yeon;Kim, Mi-Hyun
    • Journal of Nutrition and Health
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    • v.54 no.3
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    • pp.292-304
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    • 2021
  • Purpose: This study investigated the association between the mothers' use of home meal replacement (HMR) in their children's meals and the diet quality of their young children. Methods: Three hundred and thirty-seven mothers with five-year-old kindergartners in Sejong city participated in the survey from June to July 2020. The questionnaire consisted of the status of HMR use in children's meals and questions for assessing the nutrition quotient for preschoolers (NQ-P). The subjects were classified into three groups according to the frequency of HMR use in children's meals: using HMR more than three times a week (high-frequency group; [HG], n = 65), one-two times a week (moderate-frequency group; [MG], n = 145), and less than once a week (low-frequency group; [LG], n = 130). Results: The mothers' mean age was 38.3 years. The average monthly cost of purchasing HMRs was highest at 200,000-300,000 won in HG, 50,000-100,000 won in MG, and less than 50,000 won in LG (p < 0.001). The consumption frequency of processed meats, fast foods, processed beverages, and sweet & fatty snacks was significantly higher in the HG group than the other groups. The mean NQ-P score was 60.5 in HG, 63.0 in MG, and 64.5 in LG, showing a significant difference (p < 0.01). In the sub-score according to the three areas, there were no significant differences in balance and environment among the three groups. In the moderation area, however, the score was 44.1 in HG, 51.3 in MG, and 57.5 in LG Group, showing a significant difference (p < 0.001). Conclusion: The increase in HMR use was related to the decreased diet quality in the overall and moderation areas of children's diet. These results support the importance of nutrition education for mothers, which aims to reduce their children's access and exposure to processed foods, such as HMR.

A Study on Termite Monitoring Method Using Magnetic Sensors and IoT(Internet of Things) (자력센서와 IoT(사물인터넷)를 활용한 흰개미 모니터링 방법 연구)

  • Go, Hyeongsun;Choe, Byunghak
    • Korean Journal of Heritage: History & Science
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    • v.54 no.1
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    • pp.206-219
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    • 2021
  • The warming of the climate is increasing the damage caused by termites to wooden buildings, cultural properties and houses. A group removal system can be installed around the building to detect and remove termite damage; however, if the site is not visited regularly, every one to two months, you cannot observe whether termites have spread within, and it is difficult to take prompt effective action. In addition, since the system is installed and operated in an exposed state for a long period of time, it may be ineffective or damaged, resulting in a loss of function. Furthermore if the system is installed near a cultural site, it may affect the aesthetic environment of the site. In this study, we created a detection system that uses wood, cellulose, magnets, and magnetic sensors to determine whether termites have entered the area. The data was then transferred to a low power LoRa Network which displayed the results without the necessity of visiting the site. The wood was made in the shape of a pile, and holes were made from the top to the bottom to make it easier for termites to enter and produce a cellulose sample. The cellulose sample was made in a cylindrical shape with a magnet wrapped in cellulose and inserted into the top of a hole in the wood. Then, the upper part of the wood pile was covered with a stopper to prevent foreign matter from entering. It also served to block external factors such as light and rainfall, and to create an environment where termites could add cellulose samples. When the cellulose was added by the termites, a space was created around the magnet, causing the magnet to either fall or tilt. The magnetic sensor inside the stopper was fixed on the top of the cellulose sample and measured the change in the distance between the magnet and the sensor according to the movement of the magnet. In outdoor experiments, 11 cellulose samples were inserted into the wood detection system and the termite inflow was confirmed through the movement of the magnet without visiting the site within 5 to 17 days. When making further improvements to the function and operation of the system it in the future, it is possible to confirm that termites have invaded without visiting the site. Then it is also possible to reduce damage and fruiting due to product exposure, and which would improve the condition and appearance of cultural properties.

Evaluation Method of Cosmetics for the Effect of Fine Dust Adhesion Prevention Using Floating Chamber (부유챔버를 이용한 화장품의 미세먼지 부착방지 효과 평가법)

  • Kim, Woncheol;Kim, Han Jo;Boo, Yong Chool;Koh, Jae Sook;Baek, Ji Hwoon
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.46 no.4
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    • pp.319-327
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    • 2020
  • Particulate matters (PM) are small particulate pollution that decrease the function of skin barrier, which causes inflammatory skin diseases and extrinsic aging. In this study, we evaluated the effect of preventing the adherence of PMs from several cosmetic products applied to human skin using iron oxide black. The PM floating chamber consists of skin exposure area, PM inlet, floating power device, and an outlet so that PM can be naturally attached to the skin while floating in the chamber. The change in skin brightness according to the floating concentration of alternative fine dust was checked to confirm the optimal floating concentration conditions. The intensity difference (before-after intensity, Δ) before and after adhesion of iron oxide black was proportional to the amount of PM adhered. The anti-adherence effect of iron oxide black on five cosmetic products were evaluated through 20 each subjects by comparing the amount of iron oxide black adhered on the control and treatment. The difference in brightness before and after the iron oxide black attached to the skin was calculated and compared with the control group(p < 0.05). When over 150 mg of iron oxide black was adhered on the skin, the interference of intensity was low and clearly showed the skin adhered pattern. According to the application of the five cosmetics, the intensity difference was significantly lower than the control group. This means that depending on the product, it prevented the attachment of iron oxide black. This study is a safe and useful method to confirm the prevention of PM skin adherence. In conclusion, cosmetics can prevent the adherence of PM on the skin according to the formulation or ingredients characteristics.