The processes of tritium uptake, losses, transformation and organically bound tritium (OBT) build-up in crops such as potatoes, tomatoes, lettuce and wheat were studied in a set of experiments on crop' short-term exposure to tritiated water (HTO) in a greenhouse. The crops were exposed at the stage of linear growth between blossoming and ripening. The results of experiments were used to develop a model of OBT build-up in crop's storage organs.

The model allows estimate tritium uptake, losses in crop's leaves as well as its transformation in OBT and transport to storage organs of plants. The model parameters were obtained from the measured data for each crop's type by using regression analysis. The model was validated against experiments. The model can be used to assess OBT activity in storage organs of crops upon short-term exposure in the atmosphere contaminated by HTO.