The absorption of polychlorinated biphenyls, dibenzo-p-dioxins and dibenzofurans was studied in four breast-fed infants. The absorption was measured by comparing the estimated total intake and the excretion in faeces, during 48 hours, at three different time points; 1, 2 and 3 months post parta. The levels of the analysed compounds in the human milk are typical for Sweden, i.e approximately 20 ppt toxic equivalents for the dibenzo-p-dioxins and dibenzofurans and for the polychlorinated biphenyls approximately 16 ppt toxic equivalents. For most of the congeners the absorption is found to be over 95%. Higher excretion is noticed for heptachlorinated and octachlorinated dioxins.