• Korean Journal of Environmental Biology
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• v.35 no.4
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• pp.573-580
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• 2017

The oxicity assesment of Phenanthrene (PHE) has been investigated by using the rate (r) of survival and population growth in rotifer Brachionus plicatilis. The survival rate was determined after 24 h of exposure to PHE. The survival rate of PHE had no effect at a maximum of $300mg\;L^{-1}$. The r was determined after 72 h of exposure to PHE. It was observed that r in the controls (absence PHE) was greater than 0.5, but that it suddenly decreased with an increased concentration of PHE. PHE reduced r in a dose-dependent manner and a significant reduction occurred at a concentration of greater than $37.5mg\;L^{-1}$. The $EC_{50}$ value of r in PHE exposure was $63.7mg\;L^{-1}$. The no-observed-effect-concentration (NOEC) of r in PHE exposure was $18.8mg\;L^{-1}$. The lowest-observed-effect-concentration (LOEC) of r in the PHE exposure was $37.5mg\;L^{-1}$. From the results, the concentration of PHE (greater than $37.5mg\;L^{-1}$) has a toxic effect on the r of B. plicatilis in natural ecosystems. These results(including NOEC, LOEC and $EC_{50}$) might be useful for the Polycyclic aromatic hydrocarbons(PAHs) toxicity assessment in marine ecosystems.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.3
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• pp.247-256
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• 2012

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 ${\delta}^{13}C_{C21}$ and ${\delta}^{13}C_{C25}$ 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.