Study On Combined Toxic Effect Of Dispersant And Fuel Oil To Luminescent Bacteria And Glyptocidaris Crenularis

The risk of marine oil spill has been greatly increased with the development of maritime transportation and exploitation of offshore oil resources, which made a serious threat to the marine ecological environment. As one of main measures of handing oil spill, dispersants are widely used. Choosing Luminescent bacteria and Glyptocidaris Crenularis as test organism, GM-2disperants as test disperant, the toxicity effects of dispersions and emulsion to fuel oil to the aquatic organism have been studied, which can provide reference datas for the evalution of the oil spill pollution.Through the study for the toxic effects of dispersions and emulsion to fuel oil on the Luminescent bacteria, light inhition rate has been gotten under different levels of concentration. The research compares the fitting result of several functions, and concludes that the relationship between dispersion and emulsion concentration and effect can be fitted better with Generalized Logit Ⅱ and Logit function model. According to the relationship between concentration and effect, the15min EC50value of180#fuel oil dispersion and emulsion on Luminescent bacteria is220.12mg/L�'�131.24mg/L, and it proves that emulsion is more toxic than dispersion.Through the effects of dispersions and emulsion of fuel oil on the Glyptocidaris Crenularis antioxidant system, the results show enzyme activities of Glyptocidaris Crenularis in different tissues follows the law of inducing first and then inhibition during exposure period and recovery period. During exposure, the maximum induction values of SOD、CAT、GST and GSH in dispersion are113.06U/mgprot、120.72U/mgprot、132.26U/mgprot and178.67μmol/L, the maximum induction values in emulsion are119.57U/mgprot、123.02U/mgprot、140.19U/mgprot and191.03μmol/L, while compared with exposure period, both enzyme activities and degree of change have decreased, maximum induction values have also reduced during recovery. Enzymes (SOD、CAT and GST) activities and content of GSH in emulsion were significantly higher than in dispersion, however, maximum induction values of SOD and GST in emulsion are lower than those in disperant during exposure period. It can be explained that toxicity of petorleum hydrocarbons in emulsion is higher, and toxicity effects of emulsion of fuel oil on Glyptocidaris Crenularis tissue enzyme activities are greater than dispersion. From the above conclusion, Glyptocidaris Crenularis fluid changes of CAT and GSH activity is relatively more sensitive, more suitable for monitoring marine pollution of biomarkers.