Polychlorinated dibenzo-p-dioxin and polychlorinated dibenzofuran levels in human breast milk from Vietnam compared with cow's milk and human breast milk from the North American continent

PCDDs and PCDFs were determined in samples of human milk collected in 1973 and 1985 in the south of Vietnam and the levels compared to samples taken in 1970 and present day North American samples. In the Vietnam samples from the three time periods between one-half and two-thirds were positive for 2,3,7,8-TCDD. Average levels of the positives on a lipid basis, declined from about 484 ppt in 1970, to 121 ppt in 1973 and then to 12 ppt in 1985. The latter value is higher but similar to the value of about 5 ppt presently found in North American human milk and much higher than that found in samples from the north of Vietnam where Agent Orange was not used. The average body burden of 2,3,7,8-TCDD in the nursing mothers from 1970 and 1973 has been estimated to be 3.6 and 0.98 micrograms, respectively. Such an accumulation is near the value calculated by us to produce chloracne and other symptoms in some industrial workers.