• Title/Summary/Keyword: Short-life

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Detection and Measurement of Nuclear Medicine Workers' Internal Radioactive Contamination (핵의학과 종사자의 방사성동위원소 체내오염 측정)

  • Jeong, Gyu-Hwan;Kim, Yong-Jae;Jang, Jeong-Chan;Lee, Jai-Ki
    • The Korean Journal of Nuclear Medicine Technology
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    • v.13 no.3
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    • pp.123-131
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    • 2009
  • Purpose: We tested a sample of nuclear medicine workers at Korean healthcare institutions for internal contamination with radioactive isotopes, measuring concentrations and evaluating doses of individual exposure. Materials and Methods: The detection and measurement was performed on urine samples collected from 25 nuclear medicine workers at three large hospitals located in Seoul. Urine samples were collected once a week, 100~200 mL samples were gathered up to 6~10 times weekly. A high-purity germanium detector was used to measure gamma radiations in urine samples for the presence of radioactive isotopes. Based on the detection results, we estimated the amounts of intake and committed effective doses using IMBA software. In cases where committed effective doses could not be adequately evaluated with IMBA software, we estimated individual committed effective doses for radionuclides with a very short half life such as $^{99m}Tc$ and $^{123}I$, using the methods recommended by International Atomic Energy Agency. Results: Radionuclides detected through the analysis of urine samples included $^{99m}Tc$, $^{123}I$, $^{131}I$ and $^{201}Tl$, as well as $^{18}F$, a nuclide used in Positron Emission Tomography examinations. The committed effective doses, calculated based on the radionuclide concentrations in urine samples, ranged from 0 to 5 mSv, but were, in the majority of cases, less than 1 mSv. The committed effective dose exceeded 1 mSv in three of the samples, and all three were workers directly handling radioactive sources. No nurses were found to have a committed effective dose in excess of 1 mSv. Conclusions: To improve the accuracy of results, it may be necessary to conduct a long-term study, performed over a time span wide enough to allow the clear determination of the influence of seasonal factors. A larger sample should also help increase the reliability of results. However, as most Korean nuclear medicine workers are currently not necessary to monitored routinely for internal contamination with radionuclides. Notwithstanding, a continuous effort is recommended to reduce any unnecessary exposure to radioactive substances, even if in inconsequential amounts, by regularly surveying workplace environments and frequently monitoring atmospheric concentrations of radionuclides.

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Needs Accessment of Safety Education of High School Students in Seoul (서울시 고등학생의 안전교육 실태 및 요구도 조사)

  • 김민아;이명선
    • Korean Journal of Health Education and Promotion
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    • v.18 no.3
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    • pp.133-162
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    • 2001
  • Unexpected accidents in school has been gradually increased every year, and student's mistaken was the first reason of the accident. To preventing the students from Unexpected accidents in school, safety education is more important than having strong facilities to have much more strong protecting forces for the accidents. Therefore, systematic education of safety is needed most of all, and especially, strengthening safety education in school is needed. Hereby, this study is aimed at investigating and analysing the actual condition and demand of safety education. It also conducted a survey with the target of 1,255 students in the second grade of high school in Seoul from April 20 to May 19, and the result of this study is as follows. 1. In the general features of the subject of the survey, boy students and girl students occupied 50.8% and 49.2% each, and boys' high school (34.3%), girls' high school(32.2%) and co-ed(33.5%) participated in balance. In the location, north from Han river occupied 54.6%, south were 45.2%. 2. According to the status of experiencing an accident, boys were more experienced then girls(p〈0.05). From the section, home accident(56.8%) occupied most followed by school accident, traffic accident, sports accident and poisoning. The accident happening most often in detailed category is sports accident such as basket ball, foot ball and dodge ball. The actual condition of the subject's using a school health facility shows that boys students use it more often than girl students(p〈0.01) 3. In attitude toward safety, the subject showed lower interest in safety issues than other social issues. But attitude in seriality of safety problems were high. Also, they responded ‘individual citizen’(63.1%) as the one who should make efforts for safety. Regarding knowledge of preventing safety accidents in attitude toward individual safety, 42.2% answered ‘they know a little’ and 32.6% of respondents say ‘they do not know’. To a question of the degree of the subject's following safety rules, 36.4% were answered ‘keeping’ and the group using a school health facility shows more ‘keeping’ the others(p〈0.05). 4. To a question of asking if they have experienced safety education, 51.2% answered ‘yes’. Teachers who mainly take care of safety education are answered as training teacher(48.7%). As for education time, training class(51.3%) is said to have safety education most followed by health-related event and PE(Physical Education). Frequency of education shows once or twice a session (62.8%) most often, but in case of co-ed school, 5-7times a session or more(20.1%) are being practiced. Looking at education time, 1-2 hour(s)(22.1%) or for a short time(22.1%) during class are being practiced. As an education method, instruction(43.8%) and video education(32.5%) are being practiced, and when it comes to education evaluation method, ‘not practiced’(70.0%) answered. To the question if they are satisfied with school safety education, they answered more ‘no(43.1%)’ than ‘yes(6.7%)’, and the reason is that safety education class is just for formality's sake, and the fact they already know is being repeated. The contents of safety education is composed of school safety, home safety, and first aid. 5. It is turned out that 56.5% of the total boy students and 61.1% of the total girl students recognize the necessity of safety education. To the question if safety education is needed in an elementary and middle education course, 46.4% of the subject answer answered' it's necessary'. The most reason for their answers are ‘safety education is directly related to life’. 6. Regarding the requested time of safety education is ‘one hour a week’ by 55.9%. For safety education, safety education teachers(38.7%) are answered to be the most proper. As a request for safety education, video education is answered to be the most appropriate(30.6%), followed by practical skills, lecture and discussion(p〈0.05). Demand of educational evaluation, practical skills, interview and observation are answered to be needed. To the question if they want to participate in the way of demanded safety education, 41.9% of respondents answer ‘have a mind to participate in’ (41.9%). To benefits followed by completing safety education, 72.0% of respondents answer ‘agree’, and 24.7% ‘do not agree’, which means lout 4 disagrees with completing safety education. 7. Looking at demand of safety education according to the features of the subject, ‘our position for the person who has handicapped’ was answer to the most.

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Intrauterine Intraventricular Hemorrhage in Premature Infants (태아기 신생아 뇌실내 출혈)

  • Jin, Hyun-Seung;Park, Kyeng-Ah;Goo, Hyun-Woo;Yoon, Jong-Hyun;Kim, Ai-Rhan;Kim, Ki-Soo;Pi, Su-Young
    • Clinical and Experimental Pediatrics
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    • v.48 no.1
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    • pp.27-33
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    • 2005
  • Purpose : To determine incidence, characteristics and risk factors associated with intrauterine intraventricular hemorrhage(IU-IVH) among premature infants. Methods : The medical records of infants with intraventricular hemorrhage(IVH) admitted to the neonatal intensive care unit of Asan Medical Center from January 1999 to June 2003 were reviewed retrospectively. Infants whose IVH with cystic change were detected within five days of life were defined as the IU-IVH group. The control group included those without any IVH. Various maternal and neonatal factors were evaluated between the IU-IVH and control groups, and risk factors for IU-IVH were identified using multiple logistic regression analysis. Results : The incidence of IU-IVH was 49/1024(15.9%). Mothers who are younger, primiparous, use less antenatal steroid, and neonates with greater incidence of neonatal respiratory distress syndrome, had higher incidences of IU-IVH compared to neonates with normal neurosonography. Risk factors associated with IU-IVH included neonatal respiratory distress syndrome and placenta infarct by placenta biopsy. Most infants with IU-IVH were ${\geq}1,501g$, ${\geq}34$ weeks gestational age and had low grade IVH. The size of the cysts associated with IU-IVH remained the same or disappeared in 96 %. IU-IVH does not seem to affect short-term neurodevelopmental outcome although a longer period of follow-up is needed. Conculusion : IU-IVH occurred mostly in ${\geq}1,501g$, ${\geq}34$ weeks infants with grade I IVH without developmental delays. However, the high incidence of total IVH merits more attention in terms of awareness of its existence as an unusual IVH among premature infants.

현대여성(現代女性)의 의복의식(衣服意識)에 관한 조사(調査) 연구(硏究) - 서울 지역(地域)의 양복(洋服) 착용자(着用者)를 중심(中心)으로 -

  • Lee, Hee-Myung
    • Journal of the Korean Society of Costume
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    • v.2
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    • pp.73-88
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    • 1978
  • This article is an attempt to explain, at least in part, the contemporary Korean women's consciousness of Western Dreasses. As time changes, the role of clothing undergoes varisous transitions, while values and ways of life are constantly in change. It is, therefore, proper and appropriate to recognize as among the major aspects of social psychology such phenomenon as interests, understanding of clothing, the choice of a dress, and attitudes toward clothing, etc. The purpose of this study is to discover problems concerning and their clothing and their solutions, by means of a surveying approach. The method of research used is based upon questionares distributed to parents of first-year pupils in elementary schools and to female clerks working in offices, covering the period from August through October, 1976. The number of the questionares distrubuted totalled 600, and 526 were returned to the research to be utilized for analysis. The contents of the survey included such things as values concerning clothing, kinds of clothing and their practical use, the selection of clothing and the method of purchase, fashions, etc. The classification of aquisition are self-made clothing, clothing made to order and ready-made materials. It is composed of 25 items, including affirmative reasons as well as negative ones. The processing of the material returned was made by using the computer, and based upon classifications such as ages, monthly income, occupations; thus diagraming the result in percentages. The conclusion made and the improvements proposed are as follows: 1. The values of clothing were placed on the expression of the wearer's personality (32.7) and on eauty(28. 6%). The lower age group places is stress upon the expression of personality, while the higher age group stresses beauty. About 50% of wearers are contented with their clothing, their clothing, the rest of whom them indicating their dissatisfaction with what they wear. As to designs at the time of selection, about 46% indicated their preference of personal expression, 31.8% on usefulness. In selecting material, practicality is emphasized; in selecting patterns, single color is preferred. In short, personal expression and esthetic values are primary, with consideration of practicality in mind. 2. The classification of clothing according to their uses indicates the highest numbers in normal wear (home wears) and clothings to be worn outside home. As to evening dresses, (party dress) only one or two articles were checked by many, and no such article was clamed to be possessed by most. The highest ratio of wearing was shown in the case of home wear (47.3%) and clothing to be worn outside the home, which is 55.8%. The budget for one article of clothing was greatest in the case of home wear, and clothing worn outside the home. Many used both kinds of articles for the same purpose. It is desirable, therefore, that the kinds of clothing should be varied according to the purpose for which they are worn, and that clothing appropriate for that purpose should be worn. 3. The motivation for purchasing clothing was highly chosen in the item of seasonal change, which was 55.7%; Clothing deliberately made was indicated by 45.2%. In the mothods of purchasing clothing, clothing made to order and ready-made was indicated by 44.4%, which is the highest; Clothing made to order was 25.4%, and self-sewing was 1.1%, which is the lowest. (1) In the case of self-sewing, "I like it but it is very hard," was checked by 43.6%; "It is so difficult that I cannot wear such clothing" was checked by 13.3%. From these, we can conclude that the questionees are willing to make clothing by themselves, but techniques involved in sewing and at her problems involved in the skill are complicated but when those problems are eliminated there is a possibility for practice. The response checked by questionees concerning the self-sewing was, "It's economical", which is a clear indication that many questionees are positive for self-sewing. It is generally believed that ready-made clothing is cheaper, but it is not necessarily so. In consideration of the quality of clothing, self-sewing is a necessity, and it is desirable that it should be encouraged. (3) Problems involved in ready-made clothing, such as designs, skills, size (fitting) should be eliminated. When these problems are scientifically gotten rid of, it is possible that affirmative returns will be expected. Affirmative responses such as "Ready-made clothing is economical," "You can select there on the spot," are good signs that many women expect to wear ready-made clothing. It is in this sense that the prospect for ready-made clothing is brighter when much development for ready-made clothing is on the way. 4. Much concern for fashion are checked in such item of questions as "Fashionable clothing in the show window," "Clothes worn by women." The first item was checked by 50.1 %, and the second was checked by 48.6%. The reason for following fashion is "Because many people wear them," which was indicated by 30.4%. The reason for not following fashion is "It is too expensive," which was checked by 29.6%. The 26.2% of the answers indicated that "Fashionable clothing is devoid of personality," The influences of fashion over the development of fashion over the development of clothing are two-fold: Esthetic and active. It is not to be deniable that people follow fashion more or less. 1978.9>

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A Study on Jeju High School Students' Health Perception and Health Promotion Behavior (제주지역 고등학생의 건강지각과 건강증진 행위에 관한 연구)

  • Kim, Ok-Sun;Choi, In-Sook
    • The Journal of Korean Society for School & Community Health Education
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    • v.3
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    • pp.79-110
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    • 2002
  • The purpose of this study was to provide basic data necessary for creating a more successful health enhancement program, health education and health policy which can enhance health management abilities and enable a healthy school life by examining relations between high school students' health perception, who are in early adolescence, and their health promotion behavior. The subjects in this study were 813 students from 8 high schools on Jeju Island. The collected data were analyzed with t-test and one-way ANOVA through questionnaires by researcher on the basis of advance research. The findings of this study were as belows : 1. When general characteristics were considered, health perception was more significantly affected by those who were boys, whose family income was on a higher level, who scored better in school, whose parents were more concerned about their children's health, and who had experiences of being hospitalized. Especially, the more parents were concerned about their children's health, the higher the child's self-confidence on health(p<.05), anxiety on health(p<.05), practicality on disease prevention(p<.05), self-confidence on future health(p<.01), health care ability(p<.01), and family roles on health(p<.05). The less parents were concerned about their children's health, the higher the child's anxiety on disease(p<.01) and uncertainty on future health(p<.01). 2. When students' health promotion behavior was concerned, in the area of Eating Habits, having regular meals(72.9%), moderate consumption of meat(89.7%) and a balanced diet(64%) were common, whereas having a regular breakfast(37.4%) and eating vegetables and fruits(43.6%) were rare. In the area of Exercise, all subareas such as exercising 3 or 4 times a week(76.7%), more than one hour of exercise at a time(74.9%), a short distance walk(51.8%), exercise within one hour after meals(87%), and whether wanning up or not(88.6%) were above average. In the area of Personal Hygiene, all subareas such as drinking boiled water(57.3%), washing hands after using the bathroom(71%), brushing teeth after eating(42.4%), washing up after going out(50.3%), and washing hair and taking a frequent bath(77.2%) were rare. In the area of Control of Personal Relations, consulting personal problems with family(78.7%) had a positive response, whereas meeting someone new(59.8%), maintaining sound relations with the opposite sex(47.3%), having respect for one's opinion(51.5%), and maintaining peaceful relations with people(58.4%) had rare negative results. In the area of Stress Management, not being competitive(69.4%), releasing problems(62.4%) and sleeping soundly(66.2%) were common, whereas having your own ways to relieve stress(46.8%) and having your own dreams and hopes(58.5%) were rare. 3. When general characteristics were considered, as far as relations of health promotion behavior were concerned, the boys were significantly different in the area of Eating Habits(p<0.01) and Exercise(p<0.01), and the girls were in the area of Personal Hygiene. As family economic status was high and parents were concerned about their children's health, the entire areas of health promotion behavior were significantly different. Whether or not they were hospitalized made no significant difference in statistics. 4. When their regions were considered, it comparing city to town, there was no statistically significant difference in health perception and relations of health promotion behavior according to general characteristics. As seen in the results above, high school students' level of health perception and level of practicing health promotion behavior were generally low. In conclusion, by enhancing health perception, a plan for activating health education, which can implement positive health promotion behavior, should be made.

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Effect of anthelmintics on the early stage of Enterobius vermicularis (요충 초기 발육단계에 대한 구충제의 효과)

  • 조승열;강신영
    • Parasites, Hosts and Diseases
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    • v.23 no.1
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    • pp.7-17
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    • 1985
  • In order to determine the susceptible age of Enterobius vermicular is to anthelmintics and to observe the chronologie growth of female E. vermicularis in man, experimental infections were done. About 500 eggs were challenged to 19 volunteers. After 4, 8, 16, 20, 24, 28, 32 and 35 days of infection, each case was treated by either mebendazole or pyrantel pamoate. On the 40th day of infection all cases including control were treated again to terminate the experimental infection and to evaluate the effect of previous treatment. Each case collected 3-day stools to harvest the expelled worms. The results could be summarized as follows: 1. The infection rates of females were in range of 0.6~13.1 % in control cases. Because the collected worms showed comparable growth and development by day, the worms were concluded to be derived from experimental infection. 2. Cases that were treated with mebendazole on 4, 8 and 16 days after infection expelled 37.5%, 2.5% and 67.5% of the number expelled by a control case on the 40th day. Cases treated thereafter expelled no worms on the 40th day. 3. Cases that were treated with pyrantcl pamoates on 4, 8, 16, 24, 28, 32 and 35 days, expelled 90.7%, 25%, 45.3%, 8%, 2.7%, 5% and 29.3% of the number collected from control cases in respect. 4. All the worms collected were females. The total body length increased consistently and comparably from the 20th day of infection. Those collected on the 20th day were 2.5~3.0 mm long with vagina, sac-like structure and strands of ovaries; 24 day-old worms may have short uterus, 28 day-old worms had long uterus without eggs, 32 day-old worms began to produce eggs, 35 day-old worms showed wide variations in egg deposit in uterus, and 40 day-old worms had uterus filled with eggs from vulva to anal levels. From the above results, it was inferred that the life span of female Enterobius vermicularis was longer than 40 days, and the developmental stages of worms younger than 16 days resisted considerably to both mebendazole and pyrantel pamoate.

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Effect of Pulsatile Versus Nonpulsatile Blood Flow on Renal Tissue Perfusion in Extracorporeal Circulation (체외순환에서 박동 혈류와 비박동 혈류가 신장의 조직관류에 미치는 영향)

  • Kim Hyun Koo;Son Ho Sung;Fang Yang Hu;Park Sung Young;Kim Kwang Taik;Kim Hark Jei;Sun Kyung
    • Journal of Chest Surgery
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    • v.38 no.1 s.246
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    • pp.13-22
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    • 2005
  • It has been known that pulsatile flow is physiologic and more favorable to tissue perfusion than nonpulsatile flow. The purpose of this study is to directly compare the effect of pulsatile versus nonpulsatile blood flow to renal tissue perfusion in extracorporeal circulation by using a tissue perfusion measurement system. Material and Method: Total cardiopulmonary bypass circuit was constructed to twelve Yorkshire swines, weighing 20$\~ $30 kg. Animals were randomly assigned to group 1 (n=6, non pulsatile centrifugal pump) or group 2 (n=6, pulsatile T-PLS pump). A probe of the tissue perfusion measurement system $(QFlow^{TM}-500)$ was inserted into the renal pa­renchymal tissue. Extracorporeal circulation was maintained for an hour at a pump flow of 2 L/min after aortic cross-clamping. Tissue perfusion flow of the kidney was measured at baseline (before bypass) and every 10 minutes after bypass. Serologic parameters were collected at baseline and 60 minutes after bypass. Result: Baseline parameters were not different between the groups. Renal tissue perfusion flow was substantially higher in the pulsatile group throughout the bypass (ranged 48.5$\~$ 64 in group 1 vs. 65.8$\~$88.3 mL/min/100 g in group 2, p=0.026$\~$ 0.45) The difference was significant at 30 minutes bypass $(47.5{\pm}18.3\;in\;group\;1\;vs.\;83.4{\pm}28.5$ mL/min/100 g in group 2, p=0.026). Serologic parameters including plasma free hemoglobin, blood urea nitrogen, and creatinine showed no differences between the groups at 60 minutes after bypass (p=NS). Conclusion: Pulsatile flow is more beneficial to tissue perfusion of the kidney in short-term extracorporeal circulation. Further study is suggested to observe the effects to other vital organs or long-term significance.

A Case Study about Counting Uncertainty of Radioactive Iodine (131I) in Public Waters by Using Gamma Spectrometry (감마분광분석을 이용한 환경 중 방사성요오드(131I)의 측정 불확도에 관한 사례 연구)

  • Cho, Yoonhae;Seol, Bitna;Min, Kyoung Ok;Kim, Wan Suk;Lee, Junbae;Lee, Soohyung
    • Journal of Korean Society of Environmental Engineers
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    • v.38 no.1
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    • pp.42-46
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    • 2016
  • The radioactive iodine ($^{131}I$) presents in the environment through the excrete process of nuclear medicine patients. In the detecting of low level of $^{131}I$ in the public water, the counting uncertainty has an effect on the accuracy and reliability of detecting $^{131}I$ radioactivity concentration. In this study, the contribution of sample amount, radioactivity concentration and counting time to the uncertainty was investigated in the case of public water sample. Sampling points are public water and the effluents of a sewage treatment plant at Sapkyocheon stream, Geumgang river. In each point, 1, 10 and 20 L of liquid samples were collected and prepared by evaporation method. The HPGe (High Purity Germanium) detector was used to detect and analyze emitted gamma-ray from samples. The radioactivity concentration of $^{131}I$ were in the range of 0.03 to 1.8 Bq/L. The comparison of the counting uncertainty of the sample amount, 1 L sample is unable to verify the existence of the $^{131}I$ under 0.5 Bq/L radioactivity concentration. Considering the short half-life of $^{131}I$ (8.03 days), a method for measuring 1 L sample was used. However comparing the detecting and preparing time of 1, 10 L respectively, detecting 10 L sample would be an appropriate method to distinguish $^{131}I$ concentration in the public water.

Comparative toxicity of some pesticides on reproduction of Korean native freshwater Cladocerans, Moina macrocopa and Daphnia sp. (한국산 물벼룩 Moina macrocopa와 Daphnia sp.에 대한 수종 농약의 번식독성 비교)

  • Kim, Byung-Seok;Park, Yoen-Ki;Park, Kyung-Hun;Jeong, Mi-Hye;You, Are-Sun;Yang, Yu-Jung;Shin, Jin-Sup;Kim, Jin-Hwa;Yoon, Seong-Myeong;Ahn, Young-Joon
    • The Korean Journal of Pesticide Science
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    • v.11 no.4
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    • pp.246-253
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    • 2007
  • The reproduction toxicity of several pesticides on two Korean water flea was investigated to develop a new standard species used for ecological risk assessment of pesticide. Moina macrocopa and Daphnia sp. were exposed to 4 different types of pesticides over 10 and 21 days, respectively. No-ohserved effect concentration (NOEC) for synthetic pyrethroid, fenpropathrin on Moina macrocopa and Daphnia sp. were 0.17 and $0.06\;{\mu}g\;L^{-1}$, respectively. Diazinon, carbofuran and myclobutanil were in the order of their reproduction toxicity to cladocerans tested. There were large differences between Moina macrocopa and Daphnia sp. in their susceptibility to fenpropathrin, diazinon and carbofuran except myclobutanil. Daphnia sp. is more sensitive than M. macrocopa to pesticides tested. Therefore Daphnia sp. may be a good surrogate species to assess the reproduction effect of pesticides on aquatic invertebrates. M. macrocopa also be a good surrogate species because it is one of the most abundant cladocera in agricultural environment, especially rice paddy in Korea. In addition to it's ecological importance of wide spread distribution, it has also economical importance to make possible to shorten period for reproduction test using M. macrocopa due to it's short life cycle.

Effects of Butachlor on Growth of Four Freshwater Algae (Butachlor의 4종 담수조류(freshwater algae)에 대한 생장영향)

  • Park, Yeon-Ki;Bae, Chul-Han;Kim, Byung-Seok;Park, Kyung-Hoon;Lee, Jea-Bong;Shin, Jin-Sup;Hong, Soon-Sung;Cho, Kyung-Won;Lee, Kyu-Seung;Lee, Jung-Ho
    • The Korean Journal of Pesticide Science
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    • v.12 no.1
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    • pp.82-87
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    • 2008
  • Algae are vital in the primary production of the aquatic ecosystem, having been considered as good indicators of the bioactivity of pesticides. Algae have short life cycle, respond quickly to environmental change and their diversity and density can indicate the quality of their habitat. The purpose of the study was to determine the growth inhibition effects of butachlor (Tech. 93.4%) and $K_2Cr_2O_7$ (Tech. 99.5%) in Selenastrum capriconutum, Scenedesmus subspicatus, Chlorella vulgaris and Nitzschia palea during and exposure period of 72 hours. The toxicological responses of S. capriconutum, S. subspicatus, C. vulgaris and N. Palea to butachlor, expressed in individual $ErC_{50}$ values were 0.0022, 0.019, 8.67 and $4.94\;mg\;L^{-1}$, respectively. NOEC values were 0.0008, 0.0016, 5.34 and $2.92\;mg\;L^{-1}$, respectively. S. capriconutum was more sensitive than the other algae species. The toxicological responses of S. capriconutum, S. subspicatus, C. vulgaris and N. palea to $K_2Cr_2O_7$ expressed as $ErC_{50}$ values were 0.91, 0.78, 0.85 and $0.57\;mg\;L^{-1}$, respectively. NOEC values were 0.2, 0.2, 0.2 and $0.18\;mg\;L^{-1}$, respectively. Growth inhibition of S. capriconutum, S. subspicatus, C. vulgaris and N. palea from PEC of butachlor were 100, 75, 0 and 0%, respectively.