GC-MS ANALYSIS OF THE PCB SUBSTITUTE UGILEC-141 AND ITS OCCURRENCE INWASTE MINERAL-OILS

After the restrictions on production and use of PCBs, Ugilec 141, a te chnical mixture of dichlorobenzyldichlorotoluenes (DBDTs), has been us ed as a PCB substitute in hydraulic systems, In the Netherlands, the p roduction, import and use of Ugilec 141 has been forbidden since 1988, A method has been developed for the analysis of Ugilec 141 in waste m ineral oils to control waste oil import and processing. The method dev elopment was based on modification of procedures for the analysis of P CBs in oil and dioxins in fatty matrices and analysis was performed wi th gas chromatography with mass spectrometry. For sample clean-up, sev eral combinations of column chromatography with activated carbon, alum ina, and silica gel have been tested to obtain extracts free from matr ix interferences, An internal standard of C-13-labeled DBDT was examin ed to check recoveries from the clean-up procedures, Quantification wa s performed by comparison with the six most abundant peaks of an exter nal Ugilec 141 standard mixture, Validation experiments showed a linea r range from 0.25 to 60 mg Ugilec 141 kg(-1) oil, a reproducibility of 3 % and a limit of determination of 0.25 mg Ugilec 141 kg(-1) waste o il. The method was applied in a survey of 70 samples of waste mineral oils from producers all over the Netherlands; this revealed levels bel ow the limit of determination and one positive sample with a concentra tion of 5.7 +/- 0.1 mg Ugilec 141 kg(-1) oil. In an inspection inquiry one contaminated oil was found containing 116 +/- 9 g Ugilec 141 kg(- 1) oil.