DIRECT DETERMINATION OF ATMOSPHERIC LEAD BY ZEEMAN SOLID SAMPLING GRAPHITE-FURNACE ATOMIC-ABSORPTION SPECTROMETRY (GFAAS)

Atmospheric lead was collected by membrane filters using two low volume air samplers at Jülich, Stolberg, and Wetzlar, Federal Republic of Germany. Sampling times varied from 2 to 8 h. After sampling, each filter was subsampled in two cross-sections using a clean stainless steel punch (diameter 5 mm). The lead content of each subsample disc was determined directly by Zeeman GFAAS, calibrated with aqueous standard solutions and supported by solid reference materials. The distribution of lead between the subsamples was generally homogeneous, with standard deviations ranging from 11 to 37%, but typically <15% for samples with 8 h sampling time. The analysis of each filter usually took about 30 min. The differences in air quality between the three sampling locations, as measured by the lead concentrations, are discussed. In general, Stolberg appears to have the highest lead concentrations. The mass particle-size distribution of lead in the aerosol samples collected by membrane filters using a cascade impactor at Stolberg was also investigated with the same analytical technique. Using graphite platform boats as direct samplers, it is possible for the dry deposition flux of lead to be estimated. This provides a quick means of assessing the levels of lead pollution in the atmospheric environment. With lead concentrations measured in parallel, the dry deposition velocities of lead can be estimated under various meteorological conditions. Application of similar sampling and analytical techniques to other atmospheric trace metals may be possible. © 1990 Springer-Verlag.