Di-(2-Ethylhexyl) Phthalate Toxic Effect on Scenedesmus obliquus Evaluated by the Biomakers of Inhibition Rate and Pigment Content

The effect of Di-(2-ethylhexyl) Phthalate was investigated when alga Scenedesmus obliquus has been exposed to different concentrations (5, 10, 20, 40 and 80 mg · L^-1) at 24, 48, 72 and 96 hours of exposure. Toxicity test was done by using four biomarkers including growth inhibition rate and the content of chlorophyll a, chlorophyll b and carotenoid. This study indicated that with the increase concentration of Di-(2-ethylhexyl) Phthalate, the alga inhibition rate went up in a dose dependent manner. The effect of Di-(2-ethylhexyl) Phthalate on the changes of pigment content showed the treatment groups were significantly decrease compared with control group (P<;0.01). The content of carotenoid was hardly changed while it significantly decreased in higher concentration (80 mg · L^-1) (p<;0.01). It indicated that DEHP has acute toxicity on S. obliquus.