• Korean Journal of Environmental Agriculture
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• v.6 no.2
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• pp.12-21
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• 1987

Residues of some organo-chlorine pesticides on 108 solis collected from 5 sites of Chungnam avea during March 20-April 6, 1986 were investigated. 12 different kinds of Chemical components were detected showing the highest detection frequency with P.P'-DDE(67.6%) and the lowest with Heptachlor(1.8%). 4 different chemicals, ${\alpha}-BHC$, ${\gamma}-chlordane$, P.P'-DDD and P.P'-DDD and P.P'-DDE showed their average contents in the soils of 0.001 ppm and 0.005ppm for ${\beta}-BHC$, respectively. On the other hand, ${\alpha}-BHC$, ${\gamma}-chlordane$, P.P'-DDT. O.P'-DDT and P.P'-DDD showed 0.002ppm for their average contents of residues, respectively.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.721-727
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• 1998

An analytical method for simultaneous and rapid determination of organophosphorus, organochlorine, carbamate, and pyrethroid pesticides in polished rice was developed. The analysis is performed by gas chromatograph with mass selective detector (GC/MSD) in selected ion monitoring (SIM) mode. Pesticides were extracted from samples with acetone by automated Soxhlet apparatus and this extract was evaporated to dryness for the analysis. The residue was dissolved in hexane, followed by a treatment with a Sep-Pak florisil catridge. Pesticides were positively confirmed by GC/MS, retention times, and ion ratios. This analytical method allows a rapid, reliable, and a good recovery of hydrophilic pesticides. Except far captafol, captan, dichlofluanid and dichlorvos, recoveries of 42 pesticides were over 70%.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.3
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• pp.299-306
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• 1984

The influences of applications of organochlorine insecticide (HCH: Hexachlorocyclohexane, 10 ppm), fungicide (TPN: Tetrachloroisophthalonitrile, 40 ppm) and manure ($3Kg/m^2$) each or together on changes in soil microflora for consecutive years were investigated in the experimental field plots. The insecticide had a little effect on soil microbial numbers. In particular, the number of total bacteria, Gram-negative bacteria and fungi were gradually increased at the latter stage of the consecutive application, but the number of sporeforming bacteria reduced. The fungicide reduced the counts of sporeforming bacteria, actinomycetes and fungi respectively, whereas increased prominently the counts of total bacteria and Gram-negative bacteria. TPN-resistant bacteria, particulary TPN-resistant Gram-negative bacteria were gradually accumulated by the long-term application of TPN, and further the number of TPN-resistant total bacteria and the of TPN-resistant Gram-negative bacteria correlated fairly well during all the period. The influences of combined applications of both HCH and TPN on the number of soil microorganisms were equal to the respective sums of the effects of single application of each pesticide. The combined application of manure and these pesticides elevated the increasing extents of microbial numbers, while weakened the detrimental efforts of these pesticides on microbial numbers. These data suggest that the long-term application of these materials have resulted in the remarkable changes of composition of soil microflora.

• Journal of Korean Society of Environmental Engineers
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• v.34 no.12
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• pp.810-820
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• 2012

Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) contents in marine sediment and edible fish (4 species) from the estuary near the Yongho wharf in Busan were determined to assess their presence and their potential health risk to the local population through fish consumption was also assessed. Levels of ${\Sigma}PCBs$ and ${\Sigma}DDTs$ in marine sediment were 3.22~197.65 and 1.77~20.27 ng/g dw, respectively. HCHs and endosulfan sulfate concentrations in bottom sediment were 1.42~6.08, 0.56~13.89 ng/g dw, respectively. The bottom sediment in the offshore of the Yongho wharf may be characterized as semi-polluted status with potential adverse marine biological effects in terms of sediment quality guidelines of US NOAA. The mean concentrations of ${\Sigma}PCBs$ in the tissues of olive flounder (Paralichthys olivaceus), Korean rockfish (Sebastes schlegelii), file fish (Stephanolepis cirrhifer) and abbysal searobin (Lepidotrigla abyssalis) were 67.37, 10.20, 48.26, 22.81 ng/g lw, respectively. DDTs and HCHs were also detected in all fish samples. Lifetime cancer risk and target hazard quotient to local residents due to those fish consumption were found to pose negligible cancer and non-cancer risk.

• Korean Journal of Environmental Agriculture
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• v.22 no.3
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• pp.210-214
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• 2003

Pesticide residues in some vegetables collected at Noeun wholesale market in Daejeon were surveyed and assessed their risk. In 100 samples, the detection rate of pesticide was 46.0% and the rate exceed MRL was 6.0%. Commodities showing high detection rate were lettuce(85.0%), perilla leaf(80.0%) and cucumber(60.0%). Dicarboximide, organochlorine, and azole fungicides and organophosphorus and pyrethroid insecticides were detected. Detection frequency of pesticide was in the order of procymidone, chlorpyrifos, chlorothalonil, cypermethrin and EPN. When the estimated intake amount of the pesticides were compared with ADI to assess their risk, bitertanol, triflumizole and iprobenphos in perilla leaf were higher rate than the other vegetables. However the total amounts of intake of pesticides were estimated to less than 0.46% of ADI.

• Journal of Environmental Health Sciences
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• v.21 no.3
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• pp.38-47
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• 1995

The Bioconcentration factor (BCF) is used as an important criterion in the risk assessment of environmental contaminants. Also it can be used as indicator of biomagnification of environmentally hazardous chemicals through food-chain as well as a tool for ranking the bioconcentration potential of the chemicals in the environment. This paper reports the measured BCF value on Chlorothalonil in Carassius auratus(goldfish), under steady state, and examined correlation between the BCF value and the partition coefficient or acute toxicity or physicochemical properties. Carassius auratus(goldfish) was chosen as test organism and test period were 3-day, 5-day. Experimental concentrations were 0.005, 0.01 and 0.05 ppm. Chlorothalonil in fish tissue and in test water were extracted with n-hexane and acetonitrile. GC-ECD was used to detecting and quantitating of Chlorothalonil. Partition coefficient was determined by stir-flask method. $LC_{50}$ was determined on Chlorothalonil. Carbaryl and BPMC. The obtained results were as follows. 1. It was possible to determine short term BCFs of Chlorothalonil through relatively simple procedure in environmental concentrations. 2. $BF_3$ of Chlorothalonil in concentration of 0.005, 0.01 and 0.05 ppm were 2.1866$\pm$0.23446, 3.5269$\pm$0.23517, 10.2045$\pm$0.18053 and BCFs were 6.6543$\pm$0.55257, 6.9774$\pm$0.02500, 23.4576$\pm$2.06884, respectively. 3. Chlorothalonil concentration in fish extract and BCFs of Chlorothalonil were increased as increasing test concentration and prolonging test period. 4. Fate of test-water concentration on Chlorothalonil was greater than that of control-water con-centration. It is considered that greater fate of test-water concentration on Chlorothalonil is due to hydrolyzing nitrile group under the mild condition and substituting chloro group by some aromatic compounds in test water. 5. Determined logP of Chlorothalonil was 2.80. And determined $LC_{50}$ of Chlorothalonil in time of 24, 48, 72 and 96 hr were 0.1684, 0.1402, 0.1400, 0.1352(mg/l) respectively. And $LC_{50}$ of Carbaryl in above times were 19.918, 18.635, 18.466, 18.12(mg/l) respectively. $LC_{50}$ of BPMC were 10.248, 9.166, 9.087, 8.921(mg/l) respectively. 6. It is suggested that the BCF of Carbamates depend on partition coefficients. But BCF of Chlorothalonil, organochlorine pesticide, would be strongly influenced by steric, electronic effect of substituents than partition coefficient.

• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.7-16
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• 1989

Application of steam distillation on the analysis of pesticide residue in soil, water and crops was studied using the nitrogen distillation apparatus. Most pesticides which were extracted by organic solvents could be analyzed by the steam distillation method. For instance, distillations of PCNB, ${\gamma}-BHC$, ${\alpha}-or$ ${\beta}-endosulfan$, IBP, diazinon, fenthion, fenitrothion, alachlor, butachlor, pretilachlor, metolachlor, pendimethalin, benthiocarb and molinate were possible, but not simazine, atrazine and nitrofen. The optimum volume of distillate for a sufficient extraction of pesticide varied according to kind of pesticide. In general, the volume needed was little for carbamate, but much more for organochlorine. When the definite amount of distillate was obtained and then the condenser was washed by acetone, the optimum volume of distillate was less. Using the steam distillation method, the amount of organic solvent needed for one extraction of pesticide from soil, water and vegetable was less than the conventional solvent extraction method, and the analytical procedure became simpler. The process of concentration and clean up was mostly unnecessary, although a ghost peak was apparent in the gas chromatogram according to the kind of materials distilled.

• Korean Journal of Environmental Agriculture
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• v.27 no.3
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• pp.292-297
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• 2008

A bacterium, which was named to be Bacillus sp. E64-2, capable of degrading endosulfan was isolated from the environmental sample using enrichment culture technique. The Bacillus sp. E64-2 was able to degrade 99% of 10 mg/L endosulfan in the culture media within 7 days at $30^{\circ}C$. Endosulfan diol was the only intermediate by the endosulfan degrading bacterial culture and the pH value of the culture media was significantly increased to pH 8.4 from pH 7.0 after 7 days of incubation. When the endosulfan and the crude extract of the strain were incubated, endosulfan diol was a major metabolite. Both the enzymatic reaction and the pH-increasing effect contribute to the degradation of endosulfan by the bacterial culture.

• Journal of Applied Biological Chemistry
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• v.58 no.4
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• pp.291-294
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• 2015

Persistent organic pollutants (POPs) including banned organochlorine pesticides, are found in Korean agricultural environments. Their translocation from agricultural environment to major crops has been reported. In this study, the POPs in 15 different agricultural waters of the Chungchung Province were monitored and all samples were prepared, followed by liquid-liquid fractionation and column chromatography prior to analysis using gas chromatography. Among pesticide-originated persistent organic pollutants, ${\alpha}$-endosulfan was determined in the range of 0.01 to 1.13 ng/mL. ${\beta}$-Endosulfan was determined in the range of 0.01 to 0.55 ng/mL, and endosulfan sulfate was ranged from 0.13 to 1.13 ng/mL. The total sum of endosulfans reached the range of 0.38 to 1.18 ng/mL. Three pesticides being used currently were also found in samples as 2.03-2.05 ng/mL for triadimefon, 0.26-0.33 ng/mL for tolyfluanid, and 1.34-3.85 ng/mL for chlorpyrifos. Taken together, endosulfans were introduced in the agricultural waters and their fates need continuous monitoring.

• The Korean Journal of Pesticide Science
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• v.20 no.1
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• pp.7-13
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• 2016

As of many organochlorine pesticides, polychlorinated biphenyls are ubiquitous organic contaminants, which can be found in the most environmental matrices. Their toxic effects include endocrinedisrupting activity. Most researches with these toxicants performed with mixtures of congeners, namely Aroclor and related study has been done in complex environmental matrix, rather than single biosystems or pure congeners. 5 congeners were synthesized and their fates in pure microbial culture (Aspergillus niger) were determined in this study. Among biphenyl and synthetic congeners, biphenyl, PCB-1 (2-chlorobiphenyl), and PCB-3 (4-chlorobiphenyl) were rapidly transformed to hydrophilic metabolites, followed by PCB-38 (3,4,5-trichlorobiphenyl), while the degradation of PCB-126 (3,3',4,4',5-pentachlorobiphenyl) was not observed. The amounts of transformation for biphenyl, PCB-1, PCB-3, and PCB-38 were 65, 38, 52, and 2% respectively. The major metabolites of the above congeners were identified as mono- and di-hydroxy biphenyls, which are known to give adverse endocrinological effects.