Selenium contents of serum and human milk from Finland and neighbouring countries

In this work we have measured selenium concentration in 204 individual serum samples and in 105 human milk samples to compare the selenium levels in Finland after 10 years' selenium supplementation to neighbouring districts: North Estonia, Karelia in Russia, and St. Petersburg. Samples were collected between 1992 and 1994 and analysed with Zeeman graphite furnace AAS. Highest selenium concentrations were found from Finnish human milk (mean concentration in mature milk 19.2 μg/L, range 16–43 μg/L) and serum samples (mean 111.1 μg/L, range 71–163 μg/L). Selenium levels were low in the Karelian district (mean 11.5 μg/L, range 7–29 μg/L in colostrum milk), but in St. Petersburg levels were near to the levels in Finland (mean 21.9 μg/L, range 12–53 μg/L in colostrum milk and mean 88.3 μg/L, range 50–130 μg/L in serum. In Estonia we found unexpectedly low levels for selenium in human milk (mean 11.2 μg/L and range 9–14 μg/L in colostrum milk in Tallinn) and serum samples (48.2 μg/L, range 38–58 μg/L in Tallinn and 63.0 μg/L, range 31–104 μg/L in Rakvere). J. Trace Elem. Exp. Med. 10:225–232, 1997. © 1997 Wiley-Liss, Inc.