DETERMINATION OF PCBS AND LABS IN SEWAGE, SLUDGE FROM A WASTE-WATER TREATMENT-PLANT

The results from a study of the presence and temporal variability of l inear alkylbenzenes (LABs) and polychlorinated biphenyls (PCBs) in sew age sludge are presented in this work. The sewage sludges, with anaero bic treatment, were originated in the Arazuri (Pamplona, Spain) wastew ater primary treatment plant, which receives urban and industrial wast ewaters. The organic pollutants extracted from the sewage sludge by a Soxhlet apparatus. Then, PCBs and LABs were separated from the rest of the pollutants on a chromatographic column. Some different detectors were flame ionization (FID), electron capture (ECD) and mass spectrosc opy (MS). The results showed that LABs concentration varied between 1. 4 and 73.0 mg kg(-1) dry matter (d.m.). PCBs appear in smaller quantit y, between 0.050 and 0.929 mg kg(-1) (d.m.). The factor analysis of th e results allowed verification of the different origin of PCBs and LAB s.