Extensive Biodegradation of Synthetic Detergents

Abstract

THE principal surface-active constituent of most modern commercial synthetic detergents is a mixture of sodium alkylbenzene sulphonates (ABS) derived from a highly branched, low-molecular-weight propylene polymer and benzene. This material is not completely destroyed in typical activated sludge sewage treatment plants. Thus, some of it finds its way into rivers, lakes, ponds, etc., where unsightly foaming occasionally results. There is widespread belief that only part of the ABS mixture is biodegradable, and that those isomers which survive normal sewage treatment are refractory to further biological action. Contrary to this belief, I have found that essentially all isomers are truly degradable, though the rate of degradation of some of the more resistant components is, as expected, quite slow.