KINETICS AND PRACTICAL SIGNIFICANCE OF BIODEGRADATION OF LINEAR ALKYLBENZENE SULFONATE IN THE ENVIRONMENT

This paper reviews the kinetics of biodegradation of linear alkylbenze ne sulfonate (LAS) in engineered (wastewater treatment) and natural en vironment systems, focusing on work conducted in our environmental lab oratories over the past 10-15 yr. Biodegradation studies were conducte d in laboratory microcosms in which pure-chainlength [C-14]-ring-label ed LAS homologs were used to allow complete mineralization to be asses sed. In general, biodegradation rates for a series of LAS homologs (C1 0-C14) were comparable to each other and to values for naturally occur ring materials such as sugars and fatty acids. Half-lives for LAS mine ralization ranged from 1-2 d in aerobic and anaerobic sewage sludges, river water and sediments, to 1-3 wk in surface and subsurface soils a nd estuarine environments. The half-life for LAS degradation in differ ent environmental compartments, relative to its residence time in thes e compartments, makes biodegradation a practically significant removal mechanism in a broad range of aquatic, benthic and terrestrial habita ts.