Longitudinal study of chromium in human milk.

Using low temperature ashing and graphite furnace atomic absorption, the concentration of chromium in breast milk samples of 10 breast-feeding mothers was measured and the chromium intake of their totally breast-fed infants was evaluated. Ten samples were collected during 8 to 18 days and five samples during 47 to 54 days and 128 to 159 days of lactation. The milk samples represented every feed during a period of 24 hr and contained foremilk and hindmilk in equal proportions. The mean chromium concentration in the breast milk was 0.39 (SD 0.15) ng/ml and the intake 0.27 (SD 0.11) microgram/day. The mean chromium concentration, or intake in the breast milk did not significantly change with advancing stages of lactation.