Effect of petroleum hydrocarbons on the carbon and nitrogen stable isotope composition of Nitzschia closterium

Abstract

The microalgae is an important test organism of Petroleum hydrocarbon pollution. The present study was selected the N. closterium under laboratory conditions, the acute toxicity test of 180# fuel oil CE-WAF was investigated. We found the main content of the PAHs of CE-WAF were C0-N, C2-N, C1-N and C0-P by GC-MS analysis, indicating the toxicity of PAHs could affect the growth and development of microalgae. The EA-IRMS was used to analyze the carbon and nitrogen stable isotope composition of N. closterium under the CE-WAF stress. More importantly, the value of δ13C increased with the culture time at the control group, but there was no significant difference in δ13C value with increased culture time at the high (5%, 7%, and 10%) CE-WAF concentrations. In addition, the δ15N value of microalgae was increased in the culture time at the same CE-WAF concentration. However, there was no significant difference in δ15N value with increasing CE-WAF concentration at the same culture time. This study illustrated that the toxic effects of PAHs could be detected by the δ13C value to reveal the impact on marine ecosystems, and provided basic data and related theoretical support for marine pollution detection systems.