Yukio Noma

Senior Reseacher of Waste Science Section, Hiroshima Prefectural Health and Environment Center
(1-6-29 Minami-machi, Minami-ku, Hiroshima 734-0007 Japan)

Abstract

Analytical methods for polychlorinated biphenyls (PCBs), organochlorine pesticides, and dioxins, known as POPs, are reviewed. Some components in oil samples, causing severe interferences in the determination of POPs, should be almost perfectly removed through clean-up processes such as sulfuric acid treatment, alkali treatment, and column chromatography with florisil, silica gel, alumina or activated carbon. Depending on what kinds of components are in the oil sample, it is necessary to determine an appropriate combination of clean-up processes. Four types of determining equipments, a low resolution packed column GC attached by an electron capture detector (LRGC/ECD), a high resolution capillary column (HR) GC/ECD, a HRGC/low resolution (LR) mass spectrometer (MS), and a HRGC/HRMS, are tabulated in regard to their advantages and disadvantages. All of the four methods are usable in PCBs analysis at the detection limit of 0.5mg/kg in waste oil samples, but specially careful and perfect clean-up processes will be needed for the LRGC/ECD method. To accurately detect each isomer during analysis, the HRMS method is the most recommended. To analyze many polluted waste samples, a HRGC/ECD or a HRGC/LRMS is requested as the widely used rapid method. The method using an ECD or a LRMS is inferior to a HRMS in accuracy, but it will be usable for screening purposes after the accumulation of analytical data.

Key words: waste oil, clean-up, PCBs, organochlorine pesticides, dioxins