Accumulation of pollutants in sediments and their eco-toxicity in the wastewater irrigation channel of western Shenyang
沈阳西部污灌渠沉积物中污染物积累与生态毒性研究

Sediment samples were collected from several sites in the upper, mid and lower reaches of the petroleum wastewater irrigation channel in western Shenyang of China, and the concentrations of their heavy metal Cd and mineral oil were determined. The results showed that pollutants were accumulated in all test sediments, with 400-12,500 mg x kg(-1) mineral oil and 1.6-27.2 mg x kg(-1) Cd. The sediments had significant inhibition effects on plant and earthworm. The inhibition rate of root elongation based on germination test was 10%-60%. During 14 d and 28 d exposure, the mortality rate of earthworm was 0%-70% and 0%-85%, and the inhibition rate of its body weight growth was -21.9%-17.7% and -18.6%-37.0%, respectively. It indicated that a long-term irrigation with wastewater resulted in the accumulation of pollutants in channel sediments and enhanced eco-toxicity. As an important source of pollution, the migration and release of pollutants in sediments possessed potential risks to underground water and soil.