Integration of Chemical Methods and Biomarkers for Assessment of Chlorimuron-Ethyl Bioavailability in Soil

• Published in: Pedosphere 2016-06, Vol.26 (3), p.273-281
• Main Authors: REN, Wenjie, WANG, Meie, ZHOU, Qixing, TENG, Ying
• Format: Article
• Language: English
• Subjects: chemical extraction; environmental risk; organic pollutants; organic solvent; peroxidase activity; phosphate buffer solution; toxicity test; Triticum aestivum; 化学方法; 土壤有机质; 氯嘧磺隆; 溶剂提取; 生物利用度; 生物标志物; 评价; 过氧化物酶活性
• ISSN: 1002-0160; 2210-5107
• DOI: 10.1016/S1002-0160(15)60042-X

Bioavailability is a critical factor for assessing the environmental risk of organic pollutants in soil. In this study, extractions with 3 different solvents, including 2 aqueous solutions, calcium chloride（CaCl2） and a phosphate buffer solution（PBS）, and a mixture of aqueous solution and organic solvent, a PBS-methanol（8：2,volume/volume） mixture（PBS-M）, were performed to assess the bioavailability of chlorimuron-ethyl in soil in comparison to a battery of toxicity tests in wheat seedlings. The results indicated that the peroxidase（POD） activity in wheat leaves after 7 d of exposure was one of the sensitive biomarkers of chlorimuron-ethyl in soil.The extractability of chlorimuron-ethyl by all the 3 solvents decreased with exposure time, and the rate of decrease of the PBS-M extraction between 1 and 7 d of exposure was substantially higher than those of the aqueous solution extractions. Chlorimuron-ethyl gradually changed from a water-soluble form into a soil organic matter（SOM）-bound form in the soil. The PBS extraction correlated best with the POD activity in the leaves after 7 d of exposure.