【摘 要】
：
Microcosmic experiments were performed under a simulated marine environment to in-vestigate the natural attenuation of C9 aromatics using nine components(propylbenzene,isopropylbenzene,2-ethyltoluene,3-ethyltoluene,4-ethyltoluene,1,2,3-trimethylbenzene,1,
【机 构】
：
Key Laboratory of Marine Environment and Ecology,Ministry of Education,Ocean University of China,Qin
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Microcosmic experiments were performed under a simulated marine environment to in-vestigate the natural attenuation of C9 aromatics using nine components(propylbenzene,isopropylbenzene,2-ethyltoluene,3-ethyltoluene,4-ethyltoluene,1,2,3-trimethylbenzene,1,2,4-trimethylbenzene,1,3,5-trimethylbenzene,and indene).This research aims to assess the contribution of biodegradation and abiotic activity to total attenuation of C9 aromatics and ascertain the changes in the comprehensive toxicity of seawater in the natural environ-ment.The process of natural attenuation indicates the agreement with pseudo-first-order kinetics for all nine components in microcosmic experiments.The half-lives of the nine main compounds in C9 aromatics ranged between 0.34 day and 0.44 day under optimal conditions.The experiments showed that the natural attenuation of nine aromatic hydro-carbons mainly occurred via abiotic processes.Seawater samples significantly inhibited the luminescence of P.phosphoreum(the luminescence inhibition ratio reached 100％)at the be-ginning of the experiment.In addition,the toxicity declined slowly and continued for 25 days.The attenuation kinetics and changes in toxicity could be applied to explore the nat-ural attenuation of C9 aromatics in the marine environment.
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