Abstract
The biodegradation of linear alkylbenzene sulfonate (LAS) was examined in several habitats of a laundromat wastewater pond and pristine control pond. Biodegradation was determined by measuring evolution over time of 14CO2 from a trace level (50 ppb) of 14C-ring LAS added to samples obtained from the pond. Habitats investigated included pondwater, sediments, decaying plant detritus, cattail rhizosphere, duckweed phylloplane, floating cyanobacterial mat, topsoil, saturated and unsaturated subsurface soils and groundwater. In the wastewater pond, the highest biodegradative activity was associated with detritus, cattail rhizosphere, algal-bacterial mat, saturated subsoil beneath the pond and nearby topsoil. In the control pond, LAS was degraded in aerobic sediments, cattail rhizosphere, detritus and saturated subsoil immediately beneath the pond. Generally, biodegradative activity in wastewater pond habitats was higher than in corresponding control pond habitats. Key factors affecting distribution of degradative activity were LAS exposure and redox potential. This study shows that LAS degradation occurs in a wide range of environmental compartments and is higher in systems with a history of exposure.
