A biokinetic model for manganese

The International Commission on Radiological Protection (ICRP) is updating its biokinetic models used to derive dose coefficients and assess bioassay data for intake of radionuclides. This paper reviews biokinetic data for manganese and proposes a biokinetic model for systemic manganese in adult humans. The proposed model provides a more detailed and physiologically meaningful description of the behavior of absorbed manganese in the body than the current ICRP model. The proposed model and current ICRP model yield broadly similar estimates of dose per unit activity of inhaled or ingested radio-manganese but differ substantially with regard to interpretation of bioassay data. The model is intended primarily for use in radiation protection but can also serve as a baseline model for evaluation of potentially excessive intakes of stable manganese in occupational settings.

► Manganese is an essential trace element but a neurotoxin when inhaled excessively.
► Manganese-54 is an important radiation hazard in and around nuclear reactors.
► Biokinetic data for manganese are reviewed and a new biokinetic model is developed.
► The main purpose is to update the manganese model used in radiation protection.
► The model can also be applied in evaluations of manganese as a chemical hazard.