A BIOKINETIC MODEL FOR RN-222 GAS-DISTRIBUTION AND ALPHA-DOSE IN HUMANS FOLLOWING INGESTION

A biokinetic model for absorption and distribution of 222Rn in the bod y following ingestion in drinking water was developed. The rate parame ters for the model are derived from historical human data reported in experiments of Harley et al. (1958) and Hursh et al. (1965). The bioki netic model fits the human data of Hursh et al. well for whole body re tention following ingestion of 222Rn in water on an empty stomach. The equivalent dose to stem cells for stomach and colon cancer is estimat ed to be 1.6 x 10(-9) Sv B(q-1). The model calculations yield 4 and 3 calculated stomach and colon cancers from continuous intake of water a t the estimated U.S. average of 5.5 B(q) L-1.