Initial Study on Acute Toxicity of Two Typical Persistent Organic Pollutants(POPs) against Paramecium caudatum
两种典型持久性有机污染物对草履虫急性毒性初探

Dichlorodiphenyltrichloroethane (DDT) and Benzo\a\]pyrene (BaP) are ubiquitous contaminants in the environment. Acute toxic effects of DDT and BaP on a model unicellular eukaryotic organism Paramecium caudatum were studied and a dose\|dependent increase in toxicities was observed. The median lethal concentration (LC50) of DDT in 1h is 126.012 mg·L-1 and that of BaP is 180.167 mg·L-1. There exists a good linear relationship between probit and logarithm of concentrations of contaminants. Exposed to DDT and BaP at different concentrations, Paramecia caudatum exhibited some shapes. Comparably, DDT is more toxic to Paramecium caudatum than that of BaP. Sensitive to both DDT and BaP suggests that Paramecium caudatum can be used as a sensitive indicator for early risk assessment of long\|term hazards of POPs. These results provide a novel approach for developing a strategy for the abatement of water pollution and maintenance of ecosystem viability. Finally, the toxicity mechanism of two typical POPs in Paramecium caudatum is discussed.