Selenium determination in human milk in Niger: influence of maternal status.

Selenium (Se) was determined in human milk from women residing in Niamey (Niger) at different periods of lactation. To this purpose, a rapid electrothermal atomic absorption spectrometric (EAAS) method using Zeeman background correction and palladium matrix modifier was developed. Linear range (10 nmol/L-6.25 mumol/L, 0.8-494 micrograms/L), within-run (7.6%), between-run (10.4%), precision and recovery of standard addition (101 +/- 7%) were sufficient to allow routine determination of Se in breast milk. Values of breast milk Se decreased from 5 days to 6 months postpartum. No significant correlation was found between the milk Se and any of the following parameters: mother serum Se, parity, age of the mother, age of the previous child. In mother serum, Se concentration increased from delivery to 3 months postpartum and remained stable afterwards. The Se concentrations found in breast milk and in mother serum suggest that Se status is adequate in Niger.