US EPA

Soils have accumulated CDDs/CDFs both from air deposition and from direct application associated with a variety of human activities. If even limited quantities of these dioxins can re-enter the atmosphere, then soil could be an important reservoir source of dioxins. The purpose of this study is to explore the potential of soils to act as a reservoir source of CDDs/CDFs through volatilization to the atmosphere. The CDDs/CDFs are semi-volatile compounds with the lower chlorinated compounds having the highest vapor pressures. In the atmosphere, the partitioning of lower chlorinated dioxins have been observed to fluctuate between particle and vapor phases as a result of changes in ambient temperatures (Bidleman, 1988). It is has not been demonstrated, however, whether this same exchange occurs between soil and the atmosphere at ambient temperatures. This project measures changes in concentrations of dioxins in the atmosphere and relates them to nocturnal/diurnal and seasonal temperature variations. Such fluctuations could serve as evidence of dioxin volatilization from soils

Cleverly, D., D. L. Winters, G. Schweer, S. McCarthy, J. Ferrario, J. Buchert, C. Greene, C. Byrne, AND A. Dupuy. A Study Of The Diurnal And Nocturnal Measurement Of Polychlorinated Dibenzo-P-Dioxins (Cdds) And Polychlorinated Dibenzofurans (Cdfs) In Ambient Air. Ecoinforma Press, Bayreuth, GERMANY, 1999.

The full paper is available in the Downloads section. Posting of short paper approved by Ecoinforma Press, Jean-Paul-Str. 30, D-95444 Bayreuth. Fax: 49-021-54626. E-Mail: otto.hutzinger@uni-bayreth.de