For various reasons an increasing importance has been given in recent time in many parts of the world to the evaluation of the trace element pathways from environment to man. In Italy a large program was recently started based on the study in different groups of population of the relationship existing between the trace element dietary intake and the trace element content in the total excretion and in some human tissues (mainly blood). In this paper the complete data concerning the daily dietary intake, the urinary and fecal excretion, and the blood concentration referred to five population groups living in different regions of Italy will be reported. The main trace elements considered are: Ag, Co, Cr, Cs, Eu, Fe, Hg, Ni, Rb, Sb, Sn, Sc, Se and Zn; all the measurements were performed by means of non-destructive neutron activation analysis.