Positron emission tomography (PET) is a non-invasive method for studying physiological phenomena in a living subject with radiopharmaceuticals. The physical decay of radioactive radiopharmaceuticals induce ionization in subjects, which results in an absorbed dose. Developing a new radiopharmaceutical always raises the question of how much of this substance can we inject into the patient? Administering radioactive substance to patients should always be justified and the potential benefit should outweigh the risk. Determining radiation doses for new positron emitting radiopharmaceuticals is an important part of the benefit-risk assessment of the use of radioactivity.

In this study, the evaluation of radiation doses was conducted using PET imaging technology. Prior to PET/CT scanners, studies were limited to dynamic imaging of just one part of the body (brain, thorax, abdomen or skeletal muscle). However, developments in the performance of PET scanners enabled producing series of whole body PET scans. With this whole body scanning method, more source organs were evaluated per participant and the number of measurements was increased per timepoint with the same number of participants. This produced more precise temporal time-activity-curves for source organs and more precise radiation dose calculations.

Radiation doses were calculated using computer programs that are commonly used in published dosimetry studies. There were updates in the programs during the course of the study as mathematical models of the human anatomy became more sophisticated and coefficients reflecting the harm caused by radiation to tissues became more accurate.

Dosimetry is only one part in development of a new radiopharmaceutical, and based on the results in this thesis these radiopharmaceuticals can be introduced for clinical use from a radiation safety point of view.