Selenium contents of human milk and infant formulas in Spain

The selenium content of Spanish human milk samples and different milk-based and soy-based infant formulas has been estimated by using a flow injection hydride atomic absorption spectrometric method after microwave digestion o f the organic matter. Mean values of 11.4 +/- 3.7 and 10.7 +/- 4.6 ng/ml fo r colostrum and transitional milk, 8.4 +/- 3.4 and 5.3 +/- 1.9 ng/ml for ma ture milk at 1 month and up to 2 months respectively, was obtained. These v alues are close to those reported by others authors in Europe, and lower th an the ones from the US, Japan and Korea. Selenium contents of the analyzed infants' formulas ranged from 2.7 to 9.6 ng/ml and from 1.8 to 7.5 ng/ml f or soy and milk-based infant formulas, respectively. The variability in sel enium contents is large, although mean values are close to the ones given i n other European countries. Selenium contents are not usually given on the product. The selenium intakes were estimated assuming that infants fed only human milk. The intakes ranged from 2.0 to 8.4 mu g/day and from 3.4 to 12 .9 mu g/day for colostrum and transitional milk, respectively, and from 2.6 to 10.3 mu g/day for mature milk at 1 month, and from 1.2 to 8.3 mu g/day for milk up to 2 months. The analyzed infant formulas provide significantly less selenium than the 10 mu g/day corresponding to the recommended daily allowance for infants from 0 to 6 months. (C) 1999 Elsevier Science B.V. Al l rights reserved.