FECAL EXCRETION OF PCDDS/PCDFS IN A 3-MONTH-OLD BREAST-FED INFANT

Elimination of PCDDs/PCDFs through the faeces was studied in a 3-month-old breast-fed infant. There was very little excretion of the tetra- to hexa-chlorinated congeners. Also, when calculated on the basis of the I-TEs, our data suggest that almost complete absorption (> 90%) must have occurred. However, the 1,2,3,4,6,7,8-substituted dibenzo-p-dioxin and dibenzofuran as well as OCDD were highly concentrated in the stool fat (factor 5 to 12) over the concentration in the milk fat. These hepta- and octa-chlorinated congeners were apparently poorly absorbed from the intestinal tract or excreted again into the intestinal lumen. The amount of these 3 highly chlorinated congeners eliminated in the faeces was between 20% and 40% of the corresponding amount ingested with the milk (assuming 100% recovery from the diapers). Although on an absolute basis a considerable proportion of the PCDDs/PCDFs was apparently not absorbed, these congeners contribute only very little to the amount based on the sum of the I-TE values. New cotton diapers were found to contain measurable amounts of PCDDs/PCDFs, including the non-2,3,7,8-substituted ones.