• Weed & Turfgrass Science
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• v.5 no.4
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• pp.274-279
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• 2016

Aphanisticus congener is a newly recorded buprestid (Coleoptera) insect pest of turfgrass in Korea. This buprestid pest was initially found from turfgrass conservation site in a greenhouse in Jinju, Gyeongnam province, Korea in July, 2014. The Aphanisticus in the family Buprestidae is a leaf miner. A. congener is the close species of A. aeneus which was firstly reported as sugarcane leaf sucker in India. A. congener was active from early July to late August in the greenhouse. Damage by the insect led to drying out and browning of turfgrass leaf because larva fed on cell sap of leaves and adult fed on leaf surface. A. congener damaged Zoysia japonica, Z. sinica, Conodon dactylon, and Poa pratensis when adults were artificially released into potted turfgrasses in the laboratory. In green house, A. congener damaged Z. japonica, Z. macrostachya, Z. matrella, Z. sinica, Conodon dactylon, and hybrid zoysiagrass. However, no damage symptoms were observed from the same turfgrass accessions in the nearby field of the greenhouse. Thus, the new coleopteran pest may be a warm-adapted pest for turfgrass, damaging turfgrass leaf only in warmer conditions.

• Environmental Analysis Health and Toxicology
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• v.19 no.1
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• pp.1-24
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• 2004

Since dioxins became a serious concern in Korea, a significant number of investigations have been conducted to address diverse issues related to dioxins. However, the results have not been organized for ready access and use. The principal purposes of the work were to ⅰ) provide an archive of dioxin researches in Korea and ⅱ) give an overview of dioxin contamination. The focus of this work was placed on the contamination levels and characteristics concerning the waste incinerators emissions, environmental media, and biological samples(fishes/shellfishes, foods, and human body). Principal component analysis was conducted to identify common and/or unique features and the important variables associated with the congener patterns. From a comprehensive search of academic journals, research and monitoring project reports, dissertations, and periodicals of other forms, a total of 115 counts were found that met the purposes of this study. The contamination levels of various samples were summarized and compared to those reported in foreign literatures. The congener patterns varied largely with environmental media and distinguished particularly by OCDD, 1,2,3,4,6,7,8-HpCDF, and OCDF for the samples within the same media. The proximity to emission sources differentiated the congener patterns in air and soil samples by the fraction of OCDD.

• Korean Journal of Environmental Agriculture
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• v.24 no.2
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• pp.139-145
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• 2005

All 209 PCB congeners were analyzed in cheese produced in Korea and Canada. 5 Korean and 10 Canadian cheeses were purchased in supermarket in their native countries. 93 PCB congeners were found in Korean cheese; 83 congeners were detected in Canadian cheese. Total PCB concentrations were 299.81 and 200.96 pg/g w.w. in Korean and Canadian cheeses respectively; PCB concentration was 1.5 times higher in Korean than Canadian cheese. Korean TEQ concentration (0.0067 pg-TEQ/g w.w.) in cheese was similar to in Canadian cheese (0.0064 pg-TEQ/g w.w.). These PCB concentrations range was low level compared with that of other cheeses globally. The correlation coefficient $(R^2)$ of regression was high (0.752) between each PCB congener concentration in both Korean and Canadian cheese.

• Analytical Science and Technology
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• v.12 no.2
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• pp.151-158
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• 1999

This study was conducted to measure the residual PCBs in sediments of 4 great rivers in Korea by gas chromatography-mass spectrometry. From the results, PCBs were positively detected in all samples. The residue levels of total PCBs in sediments in near of SS and OS were $290.87{\mu}g/kg$ and $221.11{\mu}g/kg$, respectively. The PCBs contamination may be in association with total organic compound (TOC) in sediments. Congener 66, 74, 90, 101, 105, 110, 118, 138, 149, 153, 180, 187 as IUPAC No were predominant species found in sediments and the polyCBs detected most aboundantly in sediments were tetraCBs and pentaCBs. From the study, it appears that the PCBs contamination in sediments of 4 great rivers is not serious and the analysis from enough many sites is needed for the next survey.

• Journal of Microbiology and Biotechnology
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• v.18 no.9
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• pp.1564-1571
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• 2008

We investigated whether the threshold concentration for polychlorinated biphenyl (PCB) dechlorination may be lower in biosurfactant-amended sediments compared with biosurfactant-free samples. At PCB concentrations of 40, 60, and 120 ppm, the surfactant amendment enhanced the PCB dechlorination rate at all concentrations and the rate was also faster at higher concentrations. On a congener group basis, dechlorination proceeded largely with group A (congeners with low threshold) in both surfactant-free and -amended sediments, accumulating mainly group C (residual products of dechlorination) congeners, and surfactant enhanced the dechlorination rate of group A congeners. Since the PCB threshold concentration for the inoculum in the experiment was lower than 40 ppm, we carried out another experiment using sediments with lower PCB concentrations, 10, 20, and 30 ppm. Sediments with 100 ppm were also performed to measure dechlorination at a PCB saturation concentration. Comparison between the plateaus exhibited that the extent of dechlorination below 40 ppm PCBs was much lower than that at a saturation concentration of 100 ppm. There was no significant difference in the extent of dechlorination between surfactant-free and -amended sediments. Moreover, surfactant did not change the congener specificity or broaden the congener spectrum for dechlorination at PCB concentrations below 40 ppm. Taken together, it seems that at a given PCB concentration, dechlorination characteristics of dechlorinating populations may be determined by not only the congener specificity of the microorganisms but also the affinity of dechlorinating enzyme(s) to individual PCB congeners.

• Analytical Science and Technology
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• v.17 no.4
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• pp.347-354
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• 2004

We collected crucians (Carassius auratus) and leopard frogs(Rana pipiens) along the Nakdong River and the basin area at five locations from Koomi to Nakdong-estuary. The muscular tissue were separated and a GC-MSD system was used for quantification of PCBs. The 62 PCB congeners which represent total PCB levels were selected as analytes. We determined concentrations of PCBs and studied distribution characteristics by individual congeners and homologs. In the crucian, 24 congeners were detected and total PCB levels ranged from 0.74 to 5.41 ng/g wet weight. In the leopard frog, however, only 2 congeners were detected from Nakdong estuary only. The PCB level was 0.24 ng/g wet weight, around 22 times lower than the crucians. The PCB 153 showed the highest concentrations in the congeners and penta- and hexa-CBs showed the strong predominance which accounted for 78% of the total PCBs.

• Journal of Korean Society for Atmospheric Environment
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• v.24 no.2
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• pp.249-258
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• 2008

Historical emission data for 11 polychlorinated biphenyls (PCBs) and a regional multimedia environmental model, CoZMo-POP 2, were used to predict air concentrations and congener patterns in Korea. The total emission value for South Korea was allocated to sub-provinces and cities based on their population. The spatial distribution of PCB emissions was generally correlated with that of measured atmospheric levels, suggesting that population could be a good surrogate for the intensity of PCB emission in Korea. The simulated time trends of air concentrations well reflected those of emission with a peak in the mid-1970s and insignificant levels in the 2030s. The model predicted that the contribution of volatile PCBs had increased after emission reduction iii the 1970s. This trend would continue until the early 2030s. The measured and modeled PCB levels in the 2000s were in an agreement of an order of magnitude, and their congener patterns were very similar. Consequently, despite of high uncertainty for emission estimates, the emission data for Korea used in this study is considered to be reliable. The results of this study could be compared with simulation data based on a new emission inventory to be developed by measurements in the near future.

• Environmental Engineering Research
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• v.12 no.2
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• pp.55-63
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• 2007

PCDD/Fs monitoring was carried out to estimate the contamination level in soil samples taken in the vicinity of the various incinerators throughout South Korea from July 2003 to December 2004. The levels ranged from N.D. to 130.39 pg I-TEQ/g (d.w.) with an average concentration of 11.38 pg I-TEQ/g (d.w.). The level of PCDD/Fs in this study is similar to that of other countries. Overall, the highest mean concentration in the soil was found at 250 m from the stack. In addition, the flue gases were analyzed in order to obtain the congener profiles of the PCDD/Fs emitted from the incinerators. The concentration of I-TEQ in the flue gas ranged from 0.33 to 21.5 ng TEQ/$Sm^3$. These levels were much lower than the concentration stipulated in the Korean emission criterion(40 ng TEQ/$Sm^3$ until 2005). The comparison of the congener patterns using cluster analysis showed that the incinerators and PCP are sources of PCDD/Fs in the soil samples according to the sampling point, but the possibility of unidentified combustion sources and vehicles exists in the case of complex industrial regions.

• Animal cells and systems
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• v.9 no.1
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• pp.27-35
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• 2005

Bupleurum euphorbioides is isolated and restricted to high mountains in Korea northeastern China. Its conservation depends on whether it is threatened by inbreeding or a loss of genetic diversity. We compared the genetic variability in B. euphorbioides with B. longiradiatum, a widespread congener, to understand how they differ in their population genetic structure. Although B. euphorbioides showed a little lower genetic variability than B. longiradiatum, $F_{IS}$ statistics for most loci were strongly positive in both B. euphorbioides (0.445) and B. longiradiatum (0.553). In addition, B. euphorbioides showed higher mean $F_{ST}$ value than B. longiradiatum (0.297 vs 0.194). It might be due to the polycarpic nature of B. longiradiatum, which holds higher genetic potentials effectively in homogeneous environment than the monocarpic B. euphorbioides. The results suggested that B. euphorbioides is a genetically viable species, and that they are threatened primarily by environmental factor.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 1998.10a
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• pp.188-190
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• 1998