• Title/Summary/Keyword: fresh and aged residues

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Behaviour of the soil residues of the herbicide quinclorac in the micro-ecosystem (pot) (Micro-ecosystem(pot)중 제초제 quinclorac 토양잔류물의 행적)

  • Ahn, Ki-Chang;Kyung, Kee-Sung;Lee, Jae-Koo
    • The Korean Journal of Pesticide Science
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    • v.2 no.3
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    • pp.96-106
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    • 1998
  • Rice plants were grown for 42 days in the specially made micro-ecosystem(pot) containing two different soils treated with fresh and 60-day-aged residues of [$^{14}C$]quinclorac, respectively, to elucidate the behaviour of the herbicide quinclorac residues in the soils. Amounts of $^{14}CO_{2}$ evolved from two soils treated with different residues with and without vegetation were all less than 2.2% of the total $^{14}C$, indicating that there was little microbial degradation of quinclorac in soil. $^{14}C$-Radioactivity absorbed and translocated into rice plants from soil A and B containing fresh quinclorac residues was 8.4 and 24.2%, respectively, of the originally applied $^{14}C$, while 5.5 and 17.7%, in aged residue soils. These results indicate that larger amounts of $^{14}C$ were absorbed by rice plants from soil B with less organic matter and clay than soil A, and the uptake of [$^{14}C$]quinclorac and its degradation products decreased with aging in soil. After 42 days of rice growing, 84.5 and 61.8% of the $^{14}C$ applied freshly to soil A and B, respectively, remained in soil, whereas, in the case of aged soils, 86.3 and 67.7% of the $^{14}C$ applied did. Meanwhile, without vegetation, more than 98.3% of the $^{14}C$ applied, in both fresh and aged residues, remained in soil, suggesting that quinclorac was relatively persistent chemically and microbiologically. Most of the non-extractable soil-bound residues of [$^{14}C$]quinclorac were incorporated into the organic matter and largely distributed in the fulvic acid portion.

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Behavior of the soil residues of the fungicide hexaconazole in a rice plants-grown microecosystem (pot) (살균제 hexaconazole 토양잔류물의 벼 재배 microecosystem(pot)중 행적)

  • Kyung, Kee-Sung;Lee, Byung-Moo;Lee, Jae-Koo
    • The Korean Journal of Pesticide Science
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    • v.8 no.3
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    • pp.198-209
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    • 2004
  • In order to elucidate the behavior of the fungicide hexaconazole in soil and rice plants, rice plants were grown for 42 days in a microecosystem (pot) containing fresh and 28 day-aged soil residues of $[^{14}C]$hexaconazole. The amount of $^{14}CO_2$ evolved during 28 days of aging was 0.11 % of total $^{14}C$-radioactivity treated and the averaged weekly degradation rate was 0.03%. Mineralization rates for 42 days of rice cultivation on fresh and aged paddy soils were 0.67% of the total $^{14}C$ in case of non-rice planting on aged soil and 1.17% in case of rice planting on aged soil, whereas 1.25% in non-rice planting on fresh soil and 1.72% in case of rice planting on fresh soil, suggesting that the amounts of $^{14}CO_2$ were evolved higher from fresh soils than aged ones and from rice-planting soils than non-planting ones. The amounts of volatiles collected were very low as background levels. Most of $^{14}C$-Radioactivity was remained in soil after 42 days of rice cultivation and $^{14}C$ absorbed through rice roots was distributed more in shoots than roots and translocated into the edge of shoots of rice plants. Amounts of non-extractable $^{14}C$ in soils were higher in rice planted soil than in non-planting soil. The distribution of non-extractable $^{14}C$ was increased in the order of humin>fulvic acid>humic acid. The amounts of $^{14}C$ translocated into rotational crop Chinese cabbage were 2.36 and 3.69% of the total $^{14}C$ in case of rice planted soil containing fresh and aged residues, respectively, suggesting that small amounts of $[^{14}C]$hexaconazole and its metabolite(s) were absorbed and their bound residues were more available than their fresh ones to Chinese cabbage.

Fate of the herbicide bensulfuron-methyl in a soil/rice plant microecosystem (벼 재배 microecosystem 내에서 제초제 bensulfuron-methyl의 행적)

  • Lee, Jae-Koo;Fuhr, F.;Kwon, Jeong-Wook;Ahn, Ki-Chang;Park, Ju-Hyoung;Lee, Yong-Pil
    • The Korean Journal of Pesticide Science
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    • v.8 no.4
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    • pp.299-308
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    • 2004
  • In order to elucidate the behavior of bensulfuron-methyl, a sulfonylurea herbicide, in a soil/plant microecosystem, rice plants (Oryza sativa L.) were grown for 12 weeks in the specially made stainless steel pots (17cm I.D. $\times$ 10cm H.) containing two different paddy soils treated with fresh and 13-week-aged residues of [phenyl-$^{14}C$]bensulfuron-methyl, respectively. During the aging period, the mineralization to $^{14}CO_2$ from soil A (OM, 3.59%; CEC, 7.65 $cmol^+\;kg^{-1}$; texture, sandy clay loam) and B (OM, 1.62%; CEC, 4.51 $cmol^+\;kg^{-1}$; texture, sandy loam) amounted to 6.79 and 10.15% of the originally applied $[^{14}C]$bensulfuron-methyl, respectively. The amounts of $^{14}CO_2$ evolved from the soils with fresh residues were higher than those from the soils with aged residues. At harvest after 12-week growing, $^{14}C$-radioactivity absorbed and translocated into rice plants from soils A and B containing fresh residues of bensulfuron-methyl was 1.53 and 4.40%, while 4.04 and 6.37% in the two soils containing aged residues, respectively. Irrespective of aging and soil type, the $^{14}C$-radioactivity remaining in soil ranged from 80.41 to 98.87% of the originally applied $[^{14}C]$bensulfuron-methyl. The solvent extractability of tile soils was $39.25\sim70.39%$, showing the big differences among the treatments. Most of the nonextractable soil-bound residues of $[^{14}C]$bensulfuron-methyl were incorporated into the fulvic acid fraction$(61.32\sim76.45%)$. Comparing the microbial activity of the soils with rice plants grown with that of the soils without them, the former was $1.6\sim3.0$ times higher than the latter. However, it did not correlate with the $^{14}CO_2$ evolution.

Leaching Behavior of the Residues of Carbofuran, Bentazon, and TCAB in Soil (Carbofuran, Bentazon 및 TCAB 잔류물의 토양중 용탈)

  • Lee, Jae-Koo;Oh, Kyeong-Seok
    • Korean Journal of Environmental Agriculture
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    • v.12 no.1
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    • pp.9-17
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    • 1993
  • The leaching behavior of $^{14}C-carbofuran$, $^{14}C-bentazon$, and $^{14}C-3,3,4,4'-tetrachloroazobenzene(TCAB)$ in the forms of freshly treated, 3-month-aged, and 6-month-aged residues, respectively, was investigated in a loamy soil column system. The degradation and mobility of pesticides in soil and the possibility of the contamination of groundwater were followed by this approach: The ambient temperature of $15{\pm}2^{\circ}C$, irrigation by the constant-head method on soil columns, and leaching with 1332 ml of simulated precipitation during 90 days. While the fresh residues of $^{14}C-carbofuran$ and $^{14}C-bentazon$ were very mobile, the aged ones were remarkably reduced in their mobility. Fresh and aged residues of $^{14}C-TCAB$ were very immobile, instead. 3-Keto carbofuran phenol(2,3-dihydro-2,2-dimethyl-3-oxo-7-benzofuranol) was the major degradation product present in the leachate from the soil column containing freshly treated $^{14}C-carbofuran$, while no metabolites could be detected in the leachates from the columns containing $^{14}C-bentazon$ or $^{14}C-TCAB$.

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Uptake of the Fresh and Aged Residues of Carbofuran by Rice Plants from Soil (침투성(浸透性) 살충제(殺蟲劑) Carbofuran 토양(土壤) 잔류물(殘留物)의 벼에 의(依)한 흡수(吸收))

  • Lee, Jae-Koo;Kyung, Kee-Sung;Wheeler, W.B.
    • Korean Journal of Environmental Agriculture
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    • v.8 no.2
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    • pp.103-118
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    • 1989
  • In order to investigate the uptake of the systemic insecticide, carbofuran, 2,3-dihydro-2,2-dimethyl-7-benzofuranyl-N-methyl(arbamate) residues, fresh and aged, by rice plants, they were grown for 42 days in soils containing freshly treated (T-1), 3-month-aged (T-2), and 6-month-aged residues (T-3). The amounts of $^{14}CO_2$ evolved from $^{14}C-carbofuran$ during the 3-and 6-month aging in soil (temp. $22{\pm}1^{\circ}C$ ; moisture, 50% of the maximum water-holding capacity) were 8.9 and 26.7% of the original radioactivity applied, respectively. Mineralization of $^{14}C-carbofuran$ in soil to $^{14}CO_2$ during 42 days of rice growing was 4.4% (T-1), 11.0% (T-2), and 15.7 (T-3). The methanol extract of the 3-and 6-month-aged soils revealed that 3-keto carbofuran phenol (2,3-dihydro-2,2-dimethyl-3-oxo-7-benzofuranol) was the major metabolite, where as 3-hydroxy carbofuran (2,3-dihydro-2,2-dimethyl-3-hydroxy-7-benzofuranyl-N-methylcarbamate) turned out to be the major metabolite in the shoots by the enzymatic cleavage of the possible conjugate present in the methanol extract. Volatilization of $^{14}C-carbofuran$ in soil during 3-and 6-month-aging, and 42 days of rice growing was 0.026, 0.05, and 0.012-0.018% of the applied radioactivity, respectively. The $^{14}C-radioactivity$ which was absorbed from the soils by rice plants during 42 days of the growing period and persisted in rice plant tissues was 26.8, 21.4, and 10.3% in T-1, T-2, and T-3, respectively. The non-extractable bound residues were 8.3, 37.9, and 54.6% of the originally applied carbofuran in T-1. T-2, and T-3, respectively. The small translocation of $^{14}C-radioactivity$ in T-3 upwards suggests that major metabolite 3-keto carbofuran phenol is conjugated in roots and the low recovery in T-1 indicates the loss of carbofuran from the shoots.

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Food/Nutrition Attitudes, Views and Practices of Adults in Seoul Area (서울지역 성인의 식품.영양.건강 태도와 식품영양표시 활용실태)

  • 장남수
    • Journal of Nutrition and Health
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    • v.30 no.3
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    • pp.360-369
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    • 1997
  • Food/nutrition related views, beliefs, attitudes, and behaviors were investigated for three hundred randomly selected men and women, aged 20-60 years, residing in Seoul metropolitan area. Food/nutrition views, attitudes, and beliefs were found to vary greatly between groups of different age, sex, education and income level. Adults of 20-35 years of age showed significantly less strong views about keeping traditional food habits, while exhibiting a significantly high level of acceptance towards the use of convenience foods as compared to the adults aged 36 years or older. Food safety was found to be a major concern to most of the subjects accounting 69.7% for pesticides residues in fresh produce items, 94.7% for food additives in processed food, and 56.3% for food poisoning in foods eaten outside of the home. Male adults aged 45 years or older showed a strong tendency to rely on a few promotional food products for the maintenance of their health and for them the development and implementation of a sensible feed nutritin/health education program including a way to avoid nutrition quackery might be beneficial. Eighty percent of the subjects were found to read food labels with higher rates shown among young adults and females. Due to the virtual absence of nutrition labeling however, the percentage of subjects who idicated that they are looking for the information on nutrient content was low (<10%) compared to the rates for other informations such as date of manufacture(80.2%), expiration data(55.8%), ingredients(40.9), and additives(40.9%). Ninety one percent of the subjects indicated that they would like to see the sources for nutrition label the nutritional value of the foods. The top five most frequently (68.3%), food packages(50.7%), and radio(43.3%). Health professionals such as physicians, nurses, and nutritionists/dietitians were utilized less frequently as sources of nutrition information than lay sources, with reported rate of only 38%, 22%, and 0.7%, respectively. These results collectively suggest that strategies are to be developed to provide accurate nutrition information to adults.

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Behaviour of the soil residues of the bipyridylium herbicide, [$^{14}C$]paraquat in the micro-ecosystem (Micro-ecosystem중 bipyridylium 제초제 paraquat 토양잔류물의 행적)

  • Kwon, Jeong-Wook;Lee, Jae-Koo
    • The Korean Journal of Pesticide Science
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    • v.3 no.1
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    • pp.66-77
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    • 1999
  • In order to elucidate the fate of the residues of the bipyridylium herbicide paraquat in soil, maize plants were grown for 4 weeks on the specially-made pots filled with two different types of soils containing fresh and 6-week-aged residues of [$^{14}C$]paraquat, respectively. The mineralization of [$^{14}C$]paraquat to $^{14}CO_{2}$ during the aging period and the cultivation period of maize plants amounted to $0.13{\sim}0.18%$ and $0.02{\sim}0.17%$, respectively, of the original $^{14}C$ activities. At harvest the roots and shoots contained less than 0.1% and 0.01% of the originally applied $^{14}C$ activities, respectively, whereas the $^{14}C$ activities remaining in soil were more than 97% in both soils. The water extractability of the soil where maize plants were grown for 4 weeks was less than 1.2% of the original $^{14}C$ activities. Most of the non-extractable soil-bound residues of [$^{14}C$]paraquat were incorporated into the humin fraction. Soil pHs during the aging of soil B and after cultivation in all treatments increased. The distribution of the $^{14}C$ activities in subcellular particles of the maize plant roots was the highest in the residue fraction(incompletely homogenized tissue). Dehydrogenase activities increased after vegetation, regardless of soil aging.

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Uptake of endosulfan and procymidone from arable soil by several vegetables I (green house study) (토양 중 endosulfan과 procymidone의 작물에 대한 흡수.이행 I (실내시험))

  • Park, Hyeon-Ju;Choi, Ju-Hyeon;Park, Byung-Jun;Kim, Chan-Sub;Ihm, Yang-Bin;Ryu, Gab-Hee
    • The Korean Journal of Pesticide Science
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    • v.8 no.4
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    • pp.280-287
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    • 2004
  • We investigated the residual amounts of endosulfan and procymidone taken by vegetables grown in hydroponics culture and field conditions treated with the pesticides in order to evaluate safe cultivation concentration of the pesticides in the vegetables. Endosulfan and procymidone were selected as test pesticides because they have been reported to frequently detect in agricultural products at different concentrations. In hydroponic culture, by Chinese cabbage, procymidone was absorbed 3.8 times higher than endosulfan. The higher the pesticide concentration get, the worse the plant grew. In soil treated with 10 mg/kg of endosulfan, the pesticide absorbed by Leafy radish, Chinese cabbage and radish was less then their MRLs. In case of carlot, the residue level in soil which did not exceed its MRL was 1 mg/kg. The concentrations of procymidone in soil which did not exceed the MRLs in Leafy radish, Chinese cabbage, radish and carrot were 10, 10, 2 and 1 mg/kg, respectively Usually aged endosulfan and procymidone residues were less absorbed into crops than the fresh ones. Chinese cabbage absorbed more endosulfan and pocymidone than leafy radish, radish doing more than carrot.

Behaviour of the Soil Residues of the Acaricide-Insecticide, [$^{14}C$]Acrinathrin;I. Behaviour during Crop(Maize) Cultivation (살비살충제 [$^{14}C$Acrinathrin 토양 잔류물의 행적 규명;I. 농작물(옥수수) 재배시의 행적)

  • Lee, Jae-Koo;Kyung, Kee-Sung;Kwon, Jeong-Wook;Ahn, Ki-Chang;Jung, In-Sang
    • Korean Journal of Environmental Agriculture
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    • v.14 no.2
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    • pp.186-201
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    • 1995
  • In order to elucidate the fate of the residues of the pyrethroid acaricide-insecticide, acrinathrin in soil, maize plants were grown for one month on the specially-made pots filled with two different types of soils containing fresh and one-month-aged residues of [$^{14}C$]acrinathrin, respectively. The mineralization of [$^{14}C$]acrinathrin to $^{14}CO_2$ during the one-month period of aging and of maize cultivation amounted to $23{\sim}24%$ and $24{\sim}33%$, respectively, of the original $^{14}C$ activities. At harvest after one-month growing, the shoots and roots contained less than 0.1% and 1% of the originally applied $^{14}C$ activity, respectively, whereas the $^{14}C$ activity remaining in soil was $65{\sim}80%$ in both soils. Three degradation products with m/z 198(3-phenoxybenzaldehyde), m/z 214(3-phenoxybenzoic acid), and m/z 228(methyl 3-phenoxybenzoate) besides an unknown were identified from acetone extracts of both soils without and with maize plants after treatment of [$^{14}C$]acrinathrin, by autoradiography and GC-MS, and those with m/z 225(3-phenoxybenzaldehyde cyanohydrin) and m/z 198 (3-phenoxybenzaldehyde) from acetone extract of the Soil A treated with 50 ppm acrinathrin and grown with maize plants for 30 days were identified by mass spectrometry. These results suggested that the hydrolytic cleavage of the ester linkage adjacent to the $^{14}C$ with a cyano group, forming 3-phenoxybenzaldehyde cyanohydrin. The removal of hydrogen cyanide therefrom leads to the formation of 3-phenoxybenzaldehyde as one of the major products. The subsequent oxidation of the aldehyde to 3-phenoxybenzoic acid, followed by decarboxylation would evolve $^{14}CO_2$. Solvent extractability of the soils where maize plants were grown for 1 month and/or [$^{14}C$]acrinathrin was aged for 1 month was less than 31% of the original $^{14}C$ activity and over 95% of the total $^{14}C$ activity in soil extracts was distributed in the organic phase. Accordingly, acrinathrin turned out to be degraded rapidly in both soils and be bound to soil constituents as well, not being available to crops.

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