Abstract
Analysis of trace elements using a polarized Zeeman atomic absorption spectrophotometer was performed on breast milk, cow's milk, and a modified milk powder commonly consumed in Japan. The elements examined in the samples were cobalt, nickel, chromium, manganese, molybdenum, and iron.
Average values of contents (per g wet weight) of these elements in breast milk obtained from mothers 19-384 days post partum were 1.4ng, 3.6ng, 6.5ng, 9.5ng, 24ng and 0.32 μg, respectively and those in cow's milk were 2.4 ng, 9.5 ng, 14 ng, 27 ng, 50 ng and 0.23 μg, respectively. The ratio of contents of cobalt, nickel, chromium, manganese, and molybdenum in breast milk was similar to that in cow's milk. There was no infant formula deficient in these elements as compared to those in breast milk when the levels of trace elements were expressed per ml of 14% (w/v) milk reconstituted from each milk powder. In addition, higher contents of iron and manganese in milk powder were noted.
