According to *Nutrition During Lactation*, Institute of Medicine, National Academy Press, Washington DC, 1991, p. 129: "There is no relationship between maternal copper status and concentrations in human milk (Lonnerdal et al, 1981). Copper secretion into milk apparently is controlled, since milk copper concentrations are three to four times lower than serum concentrations." Here is the citation for Lonnerdal: Lonnerdal, B, CL Keen & LS Hurley. 1981. Iron, copper, zinc, and manganese in milk. Annu. Rev. Nutr. 1:149-174. Cindy Turner-Maffei Massachusetts, USA