Modeling the inhalation enhancement factor in prospective radiological risk assessment

Sandia National Laboratories, 1180 N. Town Center Dr. Las Vegas, NV 89144, USA

Abstract

Inhalation of suspended particulates originating from contaminated soil is an important exposure pathway that may result from disposal of long-lived solid radioactive waste. A hypothetical scenario was evaluated involving long-term irrigation of agricultural land with contaminated water and ensuing accumulation of radionuclides in surface soil. One of the factors affecting the dose from inhalation of suspended soil particulates is the radionuclide enhancement (enrichment) in airborne soil particles relative to that of the underlying soil. The enhancement factor (enrichment factor) is defined as a ratio of airborne particle activity concentration (Bq kg^-1) to surface soil activity concentration (Bq kg^-1). The values of this parameter and its effect on inhalation dose were evaluated for different soil types and inhalation exposure conditions.