The aim of the present study was to establish the population- and laboratory-specific reference intervals RIs for the Slovenian adult population for 24 trace elements TEs in blood, plasma and erythrocytes and to evaluate the impact of gender, age, seafood consumption, smoking habits and amalgam fillings on TEs levels.
Uniform RIs for non-essential and gender-specific for essential TEs in blood, plasma and erythrocytes were established. In our population, higher blood and plasma Cu, and erythrocyte Mn levels in women were found. Zn levels were higher in 30—39 years age group. Pb and Sr increased with age.
Essential TEs were inside recommended levels, and the non-essential ones were far below critical levels. Established RIs will provide an important foundation for clinical diagnostics, safety erythrocyte transfusions assessment, toxicology and epidemiological studies.
Trace elements TEs in the human body are of exogenous origin and are therefore highly dependent on diet and environmental exposure from natural and anthropogenic sources. Their levels in the human body also depend on personal characteristics gender, age, lifestyle habits, genetic variability, etc. Generally, for a group of essential elements, their biochemical functions are well known. Still, the functions of most of the presumably non-essential TEs in the human body are poorly known and understood.
As there are complex interactions between essential and non-essential TEs, it is important to monitor the presence of both non-essential and essential TEs to assess their levels and impact on biological systems [ 1 , 2 ]. The concept of reference values was developed in [ 4 ] and was followed by a Clinical and Laboratory Standard Institute CLSI document in [ 3 ].
