Won Joon Shim

Geographical distribution and accumulation features of organochlorine residues in bivalves from coastal areas of South Korea.

As a part of Mussel Watch Program in Korea, the contamination levels and accumulation features of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed for 82 bivalve samples collected from 66 sites along the entire coast of Korea. The dry weight based sigmaPCBs and sigmaOCPs ranged from 4.4 ng g(-1) to 422.0 ng g(-1) (geometric mean = 36.9 ng g(-1)) and from 9.95 ng g(-1) to 131.37 (34.88) ng g(-1), respectively. PCB was predominant in Korean coast, followed by DDTs, HCHs, and Chlordanes. From the observed log normal distribution of PCB and each OCP, low- and high-levels were defined as geometric mean +/- 1 S.D., respectively. The levels at the sites near urban and/or industrial areas often exceeded the high-levels and the spatial distributions of sigmaDDTs and sigmaCHLs were correlated with that of sigmaPCBs, indicating terrestrial input pathways. Even distribution of sigmaHCHs suggested a possibility of atmospheric input pathway of HCHs. The observed isomer ratios of DDTs, HCHs, and CHLs indicated that aging has occurred.

Biomarker responses in caged rockfish (Sebastes schlegeli) from Masan Bay and Haegeumgang, South Korea

The purpose of this study was to compare enzymatic biomarker activities in fish caged at two sites, Masan Bay (contaminated) and Haeguemgang (reference). In the present study, ethoxyresorufin O-deethylase (EROD), brain acetyl cholinesterase (bAChE), muscle acetyl cholinesterase (mAChE) and butyryl cholinesterase (mBChE) in caged rockfish (Sebastes schlegeli) were measured 0, 1, 3, 7, 14, 21 and 30 days after caging. The level of CYP1A mRNA and Protein expression was induced higher in Masan Bay at 1, 3, 7, 14 and 30 days after caging. EROD activity in the caged fish was significantly higher in Masan Bay than in Haeguemgang 3 and 7 days after caging, but not at 14 and 30 days after caging. bAChE activity was significantly inhibited at 7 and 14 days after caging in Masan Bay. However, mBChE activity was not significantly inhibited during the experiment. Taken together, the data suggest that the caged fish were exposed, at least transiently, to CYP1A inducers and ChE inhibitors, which is consistent with our previous observations.

Temporal and geographical trends in the genotoxic effects of marine sediments after accidental oil spill on the blood cells of striped beakperch (Oplegnathus fasciatus)

To determine the impact of genetic toxicity caused by the Hebei Spirit oil spill on December 7, 2007, we measured DNA damage in the blood cells of striped beakperch in vitro after exposure to extracts from sediments in the Taean area. The objective of this study was to investigate temporal changes of toxic effects caused by residual PAHs in the sediments up to 18 months after an oil spill. In conclusion, DNA damage had reduced over this 18-month period; that is, the sediments recovered quickly from the oil pollution. In addition, statistically significant correlations between PAHs and DNA damage were observed. Because the comet assay is sensitive to DNA damage induced by genotoxic substances from the polluted sediments, the comet assay can be considered a useful tool as a biomarker in investigating genetic toxicity in environmental monitoring and elucidating the recovery of oil pollution after oil spill as well.

Multiple In Vitro Bioassay Approach in Sediment Toxicity Evaluation: Masan Bay, Korea

Extracts of 21 sediment samples from Masan Bay, Korea, used in an earlier chemical measurement, were screened for their ability to induce estrogen, – and dioxin – like gene expression using the E-Assay (+), DR-CALUX assay, respectively, and to inhibit acetylcholinesterase (AChE) activity using an in vitro AChE assay. Biological impact in the industry-rich inner bay is higher than outer bay. DDTs (0.65), coplanar PCBs (0.77), HCHs (0.64), PAHs (0.61) and APs (0.53) with good correlation to E-assay (+) are seen as environmental estrogens. The highest induction of DR-CALUX response was seen again at station M12 and 15 which received sewage effluents. PCDD/DFs gave the highest correlation (0.75). Interestingly, the M12 station at the sewage treatment outlet showed the highest activity. Among the targeted chemicals APs (0.66), PCBs (0.64), PAHs (0.61) and DDT (0.49) correlated well with the AChE bioassay. Spearman rank correlation on analytical and biochemical results affirmed the ‘hot spots’ and point sources (e.g., sewage treatment and industrial outfall) and suspected toxicants. Significant correlations between organo chlorine pesticides, PCBs, dioxins and alkylphenols and their biological effects were observed.

Estimating the Global Inflow and Stock of Plastic Marine Debris Using Material Flow Analysis: a Preliminary Approach

전세계 플라스틱 해양쓰레기의 유입량과 현존량을 추정하였다. 한국에서 플라스틱 해양쓰레기의 연간 유입량(72,956 톤)은 플라스틱의 연간 소비량(5.2백만톤)의 1.4%로 추정되었다. 유출량이 0이라는 가정과 함께, 이 1.4% 유입률을 1950년부터 2013년까지 전세계 플라스틱 생산량에 적용함으로써, 2013년 전세계 연간 플라스틱 해양쓰레기 유입량은 4.2백만톤이며, 2013년말 현재 플라스틱 해양쓰레기 현존량은 86백만톤으로 추정되었다. 또한 로지스틱 모델에 따라, 석유생산량의 4%가 플라스틱으로 생산될 때 플라스틱 해양쓰레기의 최종 현존량은 199백만톤이 될 것으로 추정되었다. 유입량과 현존량은 전혀 다른 측정단위이기 때문에, 유입 저감 정책의 효과성을 평가할 수 있는 개선된 지표가 필요하다. 또한, 플라스틱 해양쓰레기 오염은 거의 회복불가능하기 때문에, 이를 예방하는 대책의 가치는 훨씬 더 높게 평가되어야 하며, 사전주의의 원칙에 따라 더 강력한 예방 대책이 시행되어야 한다. 본 연구는 제한적인 정보에 근거한 예비 연구에 해당하므로 플라스틱 해양쓰레기의 유입량과 현존량의 경향을 규명하기 위한 추가 연구가 필요하다.

Determination of Petroleum Aromatic Hydrocarbons in Seawater Using Headspace Solid-Phase Microextraction Coupled to Gas Chromatography/Mass Spectrometry

The headspace solid-phase microextraction (HS-SPME) followed by gas chromatography/mass spec- trometry procedure has been developed for the simultaneous determination of petroleum aromatic hydrocarbons such as benzene, toluene, ethylbenzene and xylene isomers (BTEX) and polycyclic aromatic hydrocarbons (PAHs) in seawater. The advantages of SPME compared to traditional methods of sample preparation are ease of operation, re- use of fiber, portable system, minimal contamination and loss of the sample during transport and storage. SPME fiber, extraction time, temperature, stirring speed, and GC desorption time were key extraction parameters considered in this study. Among three kinds of SPME fibers, i.e., PDMS (100 µm), CAR/PDMS (75 µm), and PDMS/DVB (65 µm), a 65 µm PDMS/DVB fiber showed the most optimal extraction efficiencies covering molecular weight ranging from 78 to 202. Other extraction parameters were set up using 65 µm PDMS/DVB. The final optimized extraction con- ditions were extraction time (60 min), extraction temperature (50), stirring speed (750 rpm) and GC desorption time (3 min). When applied to artificially contaminated seawater like water accommodated fraction, our optimized HS- SPME-GC/MS showed comparable performances with other conventional method. The proposed protocol can be an attractive alternative to analysis of BTEX and PAHs in seawater.

Identification of Major Crude Oils Imported into Korea using Molecular and Stable Carbon Isotopic Compositions

Stable carbon isotope ratio of oil components are known to be unaffected by weathering processes and thus has been widely used to determine the origin of spilled oil. In this study, molecular index and composition of stable carbon isotope in 15 crude oils and petroleum product were analyzed and used as oil fingerprints to determine the discriminating power of each fingerprinting method among target crude oils. Through the fingerprints of alkane distribution only Bintulu and B-C(1%) were distinguishable from other crude oils. The pristane/phytane ratio can classify the crude oils into three groups but differentiation of crude oils within a group was impossible using the ratio. The crude oils of A.L., A.S.L., Foroozan and B-C(1%) were differentiated from the other oils using PAH source recognition indexes of C2D/C2P and C3D/C3P. The usage of 4-mD/1-mD and 2/3-mD/1-mD ratio was able to distinguish A.S.L., Bintulu and Oman from the other crude oils. However the PAH source recognition ratios in the other crude oils were similar and thus they were impractical to be used for source identification among the target crude oils. Stable carbon isotope ratios of alkanes were able to uniquely specify each crude oil in the plot of and except A.L., A.M., Qatar-Marine, B-C(1%). The oil fingerprinting method using stable carbon isotope ratios of individual alkane compounds showed more discriminating power among the target crude oils than the conventional source recognition indexes of PAHs or alkanes.