Characterization of Pollution Episode With Combined Lead and Biomass Burning Contributions Based on Chemical and Isotopic Data

Two-stage sampler, the stacked filter unit, recommended by International Atomic Energy Agency (IAEA) was applied to collect fine and coarse aerosol samples from March 28 to April 8, 2002 in Changdao, Shandong province. The chemical and isotope analyses were implemented by using ICP-MS, ICP-AES, ion chromatography, and scanning electron microscope (SEM). The fine aerosol samples collected with quartz-filter were measured for organic carbon and element carbon. The precision of 206Pb/207Pb is better than ±0. 3%. The 206Pb/207Pb ratio for fine aerosol samples is 1. 111-1. 160, while for coarse aerosol samples 1. 114~1. 164. The content of Pb in fine and coarse aerosol samples varied dramatically. A lead pollution episode was observed during the period of March 30 to April 1, 2002. It may be attributable to non-ferrous metallurgical industry with typical low ratio of 206Pb/207Pb and strong association between lead and zinc. The data of ionic and carbonaceous species showed a peak value for K ion and organic carbon, indicating a fine particle predominating pollution episode. The results from SEM analysis showed the higher K-S and Si-K-S content, as an evidence of remarkable characteristics of the biomass burning emission. The pollution episode was featured by combined contribution from both biomass burning emission and lead pollution. The air mass back-trajectory and satellite information provided a clue of the origin of pollution.