Investigation of the Source of Blank Problems in the Measurement of Lead in Sub-micrometre Airborne Particulates by Inductively Coupled Plasma Mass Spectrometry

Abstract

The development of a method for the determination of trace amounts of lead in airborne fine particulates using ICP-MS for sample analysis is described. A systematic approach to the reduction of blank readings and to the identification of sources of contamination was applied, using the techniques of factorial experimental design and multi-way analysis of variance (ANOVA). The former provides an economical method for indicating significant sources of contamination to the blank readings. The latter is a statistical method for the study of the effects of these sources and their interactions. It was found that a significant contribution of the high blank readings is attributable to the ‘memory effect’ exhibited by the laboratory PTFE-ware. As a result of this study, the detection limit of the method, in terms of the mass of lead on the filter, was reduced from 20 to 1 ng.

References

1. R. L. Boeckx, Anal. Chem., 1986, 58, 275A.
2. Sub-committee on Airborne Particles, Airborne Particles, University Park Press, Baltimore, MD, 1978, p. 107.
3. D. Banerjee and G. S. Pandey, Int. J. Environ. Anal. Chem., 1989, 35, 169.
4. M. Janssens and R. Dams, Anal. Chim. Acta, 1973, 65, 41.
5. J. Usero and I. Gracia, Int. J. Environ. Anal. Chem., 1987, 30, 69.
6. N. L. Ward, R. R. Brooks, E. Roberts and C. R. Boswell, Environ. Sci. Technol., 1977, 11, 917.
7. F. Valerio, C. Brescianini and S. Lastraioli, Int. J. Environ. Anal. Chem., 1989, 35, 10.
8. A. Hunt, D. L. Johnson, J. M. Watt and I. Thornton, Environ. Sci. Technol., 1992, 26, 1513.
9. B. C. Galli, P. R. Burki, U. P. Nyffeler and P. W. Schindler, Int. J. Environ. Anal. Chem., 1989, 35, 111.
10. H. Mukai, N. Furuta, T. Fujii, Y. Ambe, K. Sakamoto and Y. Hashimoto, Environ. Sci. Technol., 1993, 27, 1347.
11. T. A. Hinners, E. M. Heithmar, T. M. Spittler and J. M. Henshaw, Anal. Chem., 1987, 59, 2658.
12. A. M. Paudyn and R. G. Smith, J. Anal. At. Spectrom., 1990, 5, 523.
13. W. T. Sturges and R. M. Harrison, Atmos. Environ., 1985, 19, 1495.
14. B. Schneider, Spectrochim. Acta, Part B, 1989, 44, 519.
15. T. A. Pakkanen, R. E. Hillamo and W. Maenhaut, J. Anal. At. Spectrom., 1993, 8, 79.
16. M. Jannssens and R. Dams, Anal. Chim. Acta, 1973, 65, 41.
17. Z. Liang, G. T. Wei, R. I. Irwin, A. P. Walton and R. G. Michel, Anal. Chem., 1990, 62, 1452.