Ecological Risk Assessment On Petroleum Hydrocarbons And Polycyclic Aromatic Hydrocarbons In Coastal Waters

Both petroleum hydrocarbons and polycyclic aromatic hydrocarbons pose damages to the marine organism and destroy the marine ecosystem.The biological components in coastal waters are facing huge threats to survival owing to serious destruction of ecological environment from the petroleum hydrocarbons pollutions.This paper bansed on risk quotient and species sensitivity distribution(SSD)was mainly aimed to study the ecological risk of petroleum hydrocarbons and polycyclic aromatic hydrocarbons(naphthalene and fluoranthene)to aquatic organisms in waters of Bohai bay Tianjin offshore from the perspective of ecological risk,which could provide scientific theory basis for ecological risk assessment in coastal waters.The main research contents and conclusions are as follows.Firstly,collected water samples from setted the sampling points and determined the environmental exposure concentration of petroleum hydrocarbons and polycyclic aromatic hydrocarbons by the standard methods.And the related results showed that the average concentration of petroleum hydrocarbons was 0.0485 mg/L,while the concentrations of polycyclic aromatic hydrocarbons in different sampling points were below the detection limit.Secondly,obtained the prediction no-effect concentration of petroleum hydr o-carbons for aquatic organisms by marine organism acute toxicity data and evaluation factors.And then,the ecological risk was evaluated using the risk quotients calculated by environment concentration and prediction-no-effect concentration of petroleum hydrocarbons.At last,the risk quotients of statistical analysis showed that: the aquatic organisms in a risk-free probability was 19%,low risk probability was 64%,the probability of risk quotients greater than 10 was 17%.Thirdly,the potential affected fractions(PAF)were obtained by the SSD models with related toxicity data,which could be used to characterize the ecological risk of the polycyclic aromatic hydrocarbons.The related data in the SSD curves mainly consisted of three types: acute toxicity data,the chronic toxicity data obtained by an acute to chronic transformation(ACT)methodology,the chronic toxicity data calculated by an acute to chronic ratio(ACR).In addition,we also evaluated the joint ecological risk of polycyclic aromatic hydrocarbons through the equivalent concentrations.And the final evaluation results show that,the PAF calculated by original data,ACR computing data,ACT computing data from naphthalene were 0.002414%,114.3%,160.4%,respectively.The PAF calculated by original data,ACR computing data,ACT computing data from fluoranthene were 39.30%,55.14%,163.6%,respectively.The joint PAF calculated by original data,ACR computing data,ACT computing data from equivalent concentration transformation were 46.44%,91.34%,94.02%,respectively.