Elemental profiling of human semen with confirmed normozoospermia: Baseline levels for 44 elements.

Background: As a consequence of the progressive decline in human semen quality in recent decades, modern epidemiological investigations have identified several trace elements that could be responsible for this phenomenon. However, their levels in semen have not been clearly elucidated, particularly for elements present in ultra-trace levels.

Methods: We aimed to determine the levels of 39 (ultra)trace elements and 5 macroelements in human semen samples with confirmed normozoospermia using ICP-based techniques. The research was amplified by analyzing blood samples from the same participants.

Results: Among the analyzed (ultra)trace elements in semen samples, Zn is the most and Tm is the least prominent. Zn levels in semen are so high that Zn should be considered as a macroelement in this matrix. The levels of Zn, Rh, Sm, Re, Ir, Tl, Na, and Ca were significantly higher in semen, while the levels of Cu, As, Rb, Gd, Sb, Tb, Tm, Lu, K, and Fe were significantly higher in blood. Correlation analysis of the levels of 44 individual elements in paired semen and blood samples revealed positive correlations between 43 of the elements, particularly for Tl and Pt. An exception was the negative correlation for Cu, which showed that its high level in semen is associated with a low level in blood and contrariwise.

Conclusion: The reported data can be used as baseline levels/reference values for 44 elements in human semen. Furthermore, the findings of this study could be relevant for further consideration of male infertility.