Tritium Hazard via the Ingestion Pathway

Abstract

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Tritium Dynamics in Mice Exposed to Tritiated Water and Diet

“…When the mice were exposed to dietary OBT, however, OBT enter directly into the free 8 HHO pool within the body accounted for a significant proportion of the cumulative dose. These results were thus consistent with more detailed models of chronic environmental exposure where organisms are exposed to both TWT and OBT and include both the dose from OBT formed by exchange with TWT (Till et al 1979) and the dose from ingestion of tritiated diet (Etnier et al 1984;Travis 1988;ICRP 1989).…”

“…The apparent independence of drinking water and diet in their contributions to TWT and OBT specific activities may account for the success of these models when 3HH0 is the primary source of 3H exposure (see also Travis 1988). When the mice were exposed to dietary OBT, however, OBT enter directly into the free 8 HHO pool within the body accounted for a significant proportion of the cumulative dose.…”

“…In their review of the key environmental and dosimetric questions relating to tritium, Till et al (1979) concluded that the total dose resulting from chronic exposure to 'HHO would increase by approximately 20% when the dose from OBT formed by exchange with TWT was included, rather than the increase of 10% predicted by classical models 33 I of occupational 3H exposure (ICRP 1979;NCRP 1979). The inclusion of doses from ingestion of tritiated foodstuffs further increased the total dose commitment from OBT (Etnier et al 1984;Travis 1988). Accordingly, more complex models, that incorporate uptake of dietary OBT and the slower clearance of OBT (Etnier et al 1984;Travis 1988;ICRP 1989), may be required for chronic environmental 3H exposure.…”

“…The inclusion of doses from ingestion of tritiated foodstuffs further increased the total dose commitment from OBT (Etnier et al 1984;Travis 1988). Accordingly, more complex models, that incorporate uptake of dietary OBT and the slower clearance of OBT (Etnier et al 1984;Travis 1988;ICRP 1989), may be required for chronic environmental 3H exposure.…”