Dosimetry of internal emitters - quo vadis?

The dosimetry of internally administered radiopharmaceuticals in nuclear me dicine procedures using MIRD formalisms and dosimetry in the case of intake s of radionuclides and ICRP methodology for the purpose of radiological pro tection are well established working practices. It should however, be remem bered that dose or dose coefficients calculated refer to a reference indivi dual, defined in terms of a mathematical phantom established on the basis o f certain biokinetic reference parameters The reference individual represen ts a typical caucasian adult of West Europe or North American origin. Recen tly, some attempts have been made to define a Reference Asian and a Referen ce Indian individual and to assess the effects of anatomical differences an d changes in the biokinetics of radiopharmaceuticals and other radionuclide s in these different reference individuals on the estimation of dose and do se coefficients in relation to the intake of internal radionuclides. The as sessment of doses to the embryo/fetus due to intake of radionuclides by pre gnant women, local dose estimates, microdosimetry, radiobiology and radiati on protection aspects relating to Auger electron emitters represent other a reas of active research in the area of dosimetry of internal emitters The p resent review summarises these different aspects of work.