OCCURRENCE AND DETERMINATION OF ORGANIC POLLUTANTS IN AEROSOL, PRECIPITATION, AND SEDIMENT SAMPLES COLLECTED AT LAKE BALATON

The results of the determination of different organic pollutants [orga nic acids, polycyclic aromatic hydrocarbons (PAHs), n-alkanes, volatil e hydrocarbons] in aerosols, precipitation, atmosphere, and sediment s amples collected at Lake Balaton are presented. Different chromatograp hic methods were used: capillary zone electrophoresis (CZE) for organi c acids, GC-MS for n-alkanes, solid-phase extraction (SPE) and HPLC fo r PAHs and thermal desorption-GC for BTEX (benzene, toluene, ethylbenz ene, m- and p-xylene) compounds. For the determination of the size dis tribution of organic compounds aerosol was collected by an 8-stage Ber ner-type low-pressure impactor. Low-molecular mass organic acids were extracted in water in an ultrasonic bath and analysed by CZE. n-Alkane s were extracted by n-hexane, cleaned up on a silica cartridge and ana lysed by GC-MS. For analysis of PAHs in aerosols, samples were extract ed in dichloromethane and acetone, cleaned on a Sep-Pak C-18 cartridge and analysed by HPLC-fluorescence detection. Enrichment of PAHs of th e precipitation samples was accomplished by SPE on a C-18 cartridge. P AHs were eluted with dichloromethane and analysed by HPLC-fluorescence detection. The detection limit was <1 ng l(-1) for several PAHs. Well dried and sieved (500-mu m sieve) sediment samples were extracted wit h dichloromethane and acetone. The extracts were cleaned and analysed by HPLC-fluorescence detection. Fourteen PAHs were determined and fluo ranthene was found to have the highest concentration at 24 mu g kg(-1) . BTEX compounds were collected by diffusive sampling on Carbopack ads orbent. Samples were analysed by a GC-thermal desorber method and one magnitude higher concentration of volatile compounds was found among t he different locations. (C) 1997 Elsevier Science B.V.