To establish causal relationships between radiation exposure and tissue effects, it is necessary to calculate the doses to critical organs and tissues and to evaluate the dose-effect relationship. The tools of non-human biota dosimetry that exist nowadays do not take into account the heterogeneous radionuclide distribution between organs and tissues. In the current study, a computational phantom of the roach body segment was developed based on the assessment of the morphometric parameters of target organs. The spine, ribs and head kidney were considered as target organs for bone and hematological effects of radiation exposure. The dose factors to convert specific activity of incorporated