Effect of linear alkyl benzene sulfonates (LAS) on the fate of phenanthrene in a model ecosystem (water-lava-plant-air)

摘要

Advanced closed chamber system was used to study the fate of phenanthrene (3-rings PAHs) in the presence of linear alkylbenzene sulphonates (LAS). The results showed mineralization and metabolism of phenanthrene are fast in the "culture solution-lava-plant-air" model ecological system. The distribution proportions of applied ~(14)C-activity in this simulative ecological system were 41 percent-45 percent, 14 percent to 10 percent and 1 percent in plant, lava and culture solution respectively, and 18 percent to 29 percent, 11 percent to 8 percent recovered in the forms of VOCs and CO_2. Main parts of the applied ~(14)C -activity exist in two forms, one is polar metabolites(25 percent) which mainly distribute in the root(23 percent), the other is unextractable part (23 percent) which have been constructed into plant root (8.98 percent), shoot (0.53 percent) or bonded to lava (13.2 percent). The main metabolites of phenanthrene were polar compounds (25 percent of applied ~(14)C -activity), and small portion of ~(14)C -activity was identified as non-polar metabolites(6 percent of applied ~(14)C-activity) and apparent phenanthrene(1.91 percent of applied ~(14)C-activity). Phenanthrene and its metabolites can be taken up through plant roots and trans located to plant shoots. The presence of LAS significantly increased the the concentration of ~(14)C-activity in the plant and production of VOCs, at the same time it decreased the phenanthrene level in the plant and the production of CO_2 at the concentration of 200 mg/L.