Evaluation of dioxin-like chemicals in pooled human milk samples collected in Australia Original Research Article

Human milk samples were collected and analysed for the levels of polychlorinated dibenzodioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and selected dioxin-like polychlorinated biphenyls (PCBs). In total, 157 individual samples collected during 2002 and 2003 as well as 24 samples collected in 1993 were analysed as 20 pools. Results PCDDs, PCDFs and dioxin-like PCBs were detected in all pooled samples. For samples collected during 2002/2003, the TEQDFP ranged from 6.0 to 15.2 pg TEQ g−1 lipid with an average of 9.0 pg TEQ g−1 lipid. The average lipid content was 3.7 ± 0.5%. No systematic differences were observed in the levels of PCDDs, PCDFs and PCBs in human milk samples collected from different regions of Australia during 2002/2003. For samples collected in 1993 and analysed as pools, the mean level, expressed as TEQDFP was 16 ± 1.4 pg TEQ g−1 lipid. The average lipid content was 3.9 ± 0.7%. Conclusion The levels of PCDDs, PCDFs and dioxin-like PCBs in the human milk of Australian women are both low compared to international levels and similar across all regions of Australia. Consistent with world-wide trends, the levels of PCDDs, PCDFs and dioxin-like PCBs have decreased over a 10 year period from 1993 to 2003 by approximately 40%.