科研之友
微信
新浪微博
Facebook
分享链接
摘要
Eco-risk of an organic pollutant in soil is quite influenced by the property of the soil and contamination history. To evaluate the influence of these factors on the availability of organic pollutants, earthworm accumulation of pyrene in six different soils were studied in this paper used unaged and aged samples. Moreover, butanol extraction and supercritical fluid extraction (SFE) of pyrene in these samples were determined simultaneously, and the relationship between bioaccumulation and extraction by butanol and SFE before and after aging were investigated in order to find a rapid method to predict the bioavailability. The results showed that, for unaged samples, percentages of pyrene accumulated by the earthworms (Eisenia foetida), extracted by butanol and mild supercritical fluid were 1.9-18.5%, 41.8-50.8% and around 50%, respectively. Generally, the percentages of the earthworm accumulation decreased significantly and butanol extraction decreased slightly with the content of soil organic matter (SOM) in soils. Clay content might also influence pyrene availability when SOM content is smaller than 1%. However, mild SFE could not differentiate the availability of the pyrene in unaged soils. Both the bioavailability and the chemical availability of pyrene decreased significantly after aged in soils for 120 days, and the percentages of availability by the three test methods were 0.87-3.65%, 18.7-27.6% and 12.9-28.2%, respectively. A correlation relationship study of pyrene extractability by butanol and mild SFE with bioavailability to earthworm uptake for aged soils suggested that mild SFE was a better approach to predict the bioavailability of organic chemicals in field soils compared to butanol extraction.
