DEVELOPMENT OF AN ANALYTICAL PROCEDURE TO STUDY LINEAR ALKYLBENZENESULPHONATE (LAS) DEGRADATION IN SEWAGE SLUDGE-AMENDED SOILS

A procedure for determining linear alkylbenzenesulphonates (LASs) in s ewage sludge and amended soils has been developed. Extraction by sampl e treatment with 0.5 M potassium hydroxide in methanol and reflux was compared with a previously described extraction procedure in Soxhlet w ith methanol and solid sodium hydroxide in the sample. Repeatability r esults were similar with savings in extraction time, solvents and evap oration time. A clean-up method involving a C,, cartridge has been dev eloped. Analytes were quantified by a reversed-phase HPLC method with UV and fluorescence detectors. Recoveries obtained were higher than 84 %. The standing procedure was applied to high doses of sewage sludge-a mended soils (15%) with increasing quantities of added LASs. Degradati on data for a 116-day period are presented.