[Serum selenium levels in school children: results and health assessment]

In Germany, where geogenic selenium concentrations are low, only few data on selenium status in children are available. Aim of the study was to investigate serum selenium concentrations of children in a population-based sample and to additionally investigate spatial and temporal differences.

In three consecutive cross sectional studies the selenium concentration in serum was determined in 1,918 children (mean age 10.3 years) from four study areas. Potential factors of influence were assessed by questionnaires filled in by parents and physicians, respectively. Selenium determination was done by hydride atomic absorption spectrometry after microwave digestion.

Mean selenium concentrations for the subcollectives ranged from 54.5 +/- 10.5 micro g/l to 71.9 +/- 15.1 micro g/l. The minimum observed was 14 micro g/l, the maximum 216 micro g/l. Turkish children had lower selenium concentrations than German children and children of other nationality, respectively. Controlling for sex and year of investigation German children from Stuttgart had significantly lower selenium concentrations than children from Aulendorf/Bad Waldsee. In the same regression model for the period from 1995/96 to 1998/99 a decreasing trend was found to be significant. However, the regression model only explains a very small part of variance.

The selenium concentrations determined in this study are in the range also found in other studies in children from Germany. They are far below the toxicologically relevant range, which starts at about 600 micro g/l. The 5 th percentile in nearly all subcollectives was below the threshold limit of the lower tolerable selenium concentration of 45 micro g/l. For children from south Germany deficiency of selenium is therefore more to be suspected than a burden relevant to health. Selenium supplementation should however be considered thoroughly. Balanced nutrition is also a main factor for an optimum selenial supply.