Shift of combined ecotoxicity index in petroleum polluted soils during a bacterial remediation

Introduction: Bioremediation has been shown to be an effective strategy for removing toxic pollutants from the environment, particularly organic chemicals such as petroleum hydrocarbons. This paper investigates changes in toxicity of petroleum-contaminated soil a result microbial remediation processes. Methods: Changes ecotoxicity contaminated were examined using plant, earthworm, enzyme activity and luminescent bacteria tests. Results: The results showed that bioremediation could effectively degrade hydrocarbon (C 10 –C 40 ) pollutants. After 42 days remediation, content Group A (bioaugmented polluted wetland soil) decreased 1.66 g/kg 1.00 g/kg, degradation rate was 40.6%. B farmland 4.00 1.94 51.6%. During progress, ecological first increased then decreased. photosynthetic pigment index higher plant test, earthworm survival catalase all good agreement with relative luminescence extracted DCM/DMSO bacterial test. significantly after remediation. Specifically, wheat inhibited during whole process (remediation days), minimum on day 21. 7-day 14-day earthworms gradually process, increased, at end than beginning. Soil negatively correlated (−0.988, −0.989). reached maximum 21st luminosity dichloromethane/dimethyl sulfoxide extracts 26.3% 16.3%, respectively. Conclusion: Wheat content, rate, can better indicate process.