Organochlorine compounds in breast-fed vs. bottle-fed infants: preliminary results at six weeks of age

Abstract

Background: Polychlorinated biphenyls (PCBs), hexachlorobenzene (HCB), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) are ubiquitous compounds with carcinogenic and teratogenic properties. They are chemically very stable and lipophilic and, therefore, accumulate in our food-chain. They are prenatally transmitted from mother to foetus, and mother's milk due to its high lipid content is an elimination pathway of special importance. Therefore, breast-feeding has been held responsible for elevated concentrations of these organochlorine compounds as well as for harmful effects in children later in life. Methods: Blood samples (2.5 ml) were taken from each 10 breast-fed and bottle-fed infants at 6 weeks of age. Blood specimens were immediately centrifuged, and serum was stored in glass tubes at −20 °C until analysis. Three higher chlorinated PCB congeners (IUPAC nos. 138, 153 and 180), HCB, and the organic metabolite of DDT, p,p≪-DDE, were analysed with capillary gas chromatography with electron capture detection. Reliability was tested with gas chromatography-mass spectrometry. Results: There were no differences between the study groups of breast-fed and bottle-fed infants with regard to sex distribution, gestational age, birth-weight, age of the mothers, and smoking behaviour of the parents. In contrast, serum concentrations of all organochlorine compounds were significantly higher (P<0.0001) in breast-fed than in bottle-fed infants (mean): PCB 138, 0.38 vs. 0.10 μg/l; PCB 153, 0.49 vs. 0.1 μg/l; PCB 180, 0.31 vs. 0.04 μg/l; ΣPCB, 1.19 vs. 0.29 μg/l; HCB, 0.13 vs. 0.04 μg/l; p,p≪-DDE, 1.05 vs. 0.18 μg/l. Conclusions: Breast-feeding significantly increases the pollution of our infants with different organochlorine compounds as early as at 6 weeks of age. The progress of the present study will show whether this pollution will further increase with longer duration of breast-feeding, and whether breast-feeding bears any health risks for our offspring.