Toxicity Response Of Heterocapsa Circularisquama And Nereis Succinea On Petroleum Ydrocarbons

Now marine pollution levels, especially oil pollution emerging, leading to marine ecological environment continues to be destroyed. Deteriorating water quality in coastal waters, petroleum hydrocarbons as the main material of oil pollution, get attention. Petroleum hydrocarbon affect the growth of the organism, and it will teratogenic and mutagenic, it also affecting the normal life of the larvae of marine life, and bring long-term and very serious effects on marine life.Heterocapsa circularisquama was selected as the other indicator organism for petroleum hydrocarbons pollution. Acute toxicity experiments were conducted and found that cell density and chlorophyll varied significantly. Chlorophyll showed to be more sensitive indicator for petroleum hydrocarbons. Sub-acute toxicity test was conducted to investigate the effects of petroleum hydrocarbons on MDA content and antioxidant enzymes(SOD ? GR ? GSH-Px) and antioxidant GSH content of Heterocapsa circularisquama. The results indicate that after exposed to petroleum hydrocarbons MDA content increased significantly, SOD?GSH-Px?GR activities firstly increased and then decreased, while GSH contend showed no significant changes at low petroleum hydrocarbons concentrations.Nereis as one of benthic biological have a widely distributed range, and easy access to the individual, marine pollution by oil is very serious, so Nereis be selected on the toxic effects experiment about petroleum hydrocarbons. It was found that acute toxicity test with the greatest concentration of 9mg/L of Nereid are not lethal effect, so we have done a sub-acute toxicity test after that, to explore the extent of production and scavenging of oxygen free radicals in the Nereis' body, to judgment Nereis' cell damage. Selecting MDA content and SOD? CAT? POD?GSH-Px activity as determination of indexes, MDA content is an indirect reflection of Nereid oxygen free radicals involved in lipid peroxidation case. The antioxidant enzymes may reflect the case of antioxidant system of Nereis clearing oxygen free radicals. The results show that MDA content and the 4 enzymes activity of Nereis changed significantly when exposed to petroleum hydrocarbons. MDA content? CAT and GSH-Px activity are potential indicators for petroleum hydrocarbons pollution due to their dramatic fluctuations observed during the experiment.