DEGRADATION OF LINEAR ALKYLBENZENE SULFONATE IN SOIL COLUMNS

摘要

This study investigated the ability of a microbial community to degrade linear alkylbenzene sulfonate (LAS) in soil columns under water-saturated conditions. The microbial mineralization of LAS was further studied in a batch experiment using pre-exposed and unexposed soil as well as soil from the inlet and outlet of the columns. The LAS (4 mg/L) was added continuously to the columns. Three pulses of ~(14)C-labeled LAS (~(14)C-dodecyl-[6]-benzene sulfonate) were added at intervals of 2 weeks, and the mineralization was measured as production of ~(14)CO_2. The primary degradation of LAS was close to 100 in the columns, whereas the mineralization of the ~(14)C-labeled compound reached only 9. The degradation products of LAS proved to be significantly less sorbtive than LAS itself. In the batch experiment, mineralization of LAS occurred in unexposed soil after a short lag phase. The mineralization proved to be more dependent on a high representation of biomass than on previous exposure to LAS.