| Abstract: | A sensitive and selective determination of cadmium in aerosols by flameless atomic absorption spectrometry is described. By two successive treatments in 0.1 M suprapure nitric acid, the cadmium is removed from the paper filter on which the particulates have been collected. Routinely 10–50 μl of the 100-ml solution are injected into a graphite oven and the % absorption at 228.8 nm is measured. If half a 24-h filter (400 m3 air) is used, the dilution is made to 50 ml and 50 μl is injected, an unusually low concentration of 0.20 ng m-3 can be determined quantitatively with a relative standard deviation of 10%. The reproducibility of the complete procedure is 4.8%. An interlaboratory comparison indicated that the accuracy is very good. The same solution can also be used for lead determination mostly without any further dilution. As an application, the cadmium concentrations were measured on two different days at 14 stations of the nationwide sampling network, and the influence of nonferrous industries on the cadmium levels is shown. |
