Sasamoto Takeo, Horii Shozo, Ibe Akihiro, Takada Naoko, Shirota Kinji
Division of Food Contaminants, Tokyo Metropolitan Institute of Public Health, Tokyo 169-0073, Japan.
Chemosphere. 2006 Jul;64(4):642-9. doi: 10.1016/j.chemosphere.2005.10.054. Epub 2005 Dec 20.
Breast milk is known to discharge dioxins from the human body. However, to date, no direct comparison has been made of the concentrations of dioxin analogues in breast milk obtained from identical population after successive deliveries. We present here follow-up survey results of PCDDs, PCDFs, and dioxin-like PCBs concentrations in human breast milk samples from 35 women living in Tokyo from whom samples had been obtained and analyzed to determine the corresponding concentrations in the past. The average concentrations of total PCDDs, PCDFs, dioxin-like PCBs were 8.5, 5.5, 11 TEQ pg/g fat for the first samples and 5.4, 4.0, 6.6 TEQ pg/g fat for the second samples, respectively. The degrees of reduction of total PCDDs and total dioxin-like PCBs were higher than that of total PCDFs because 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and 3,3',4,4',5-PeCB (#126), which were the predominant congeners among PCDDs, PCDFs, and dioxin-like PCBs, respectively, had different degrees of reduction. Moreover we observed a significant increase of the concentrations of PCDDs, PCDFs, and dioxin-like PCBs in samples from three women in this follow-up survey, and the patterns of increased isomers differed among the three samples. It was conjectured that the increase of the concentrations was due mainly to dietary intake between deliveries. It is important for pregnant women to have a balanced diet to mitigate the exposure of infants to these chemicals.
众所周知，母乳可排出人体中的二噁英。然而，迄今为止，尚未对同一人群连续分娩后母乳中二噁英类似物的浓度进行直接比较。我们在此展示了对东京35名女性母乳样本中多氯二苯并对二噁英（PCDDs）、多氯二苯并呋喃（PCDFs）和类二噁英多氯联苯（PCBs）浓度的跟踪调查结果，这些女性的母乳样本在过去已采集并分析过以确定相应浓度。第一批样本中总PCDDs、PCDFs、类二噁英PCBs的平均浓度分别为8.5、5.5、11毒性当量皮克/克脂肪，第二批样本分别为5.4、4.0、6.6毒性当量皮克/克脂肪。总PCDDs和总类二噁英PCBs的降低程度高于总PCDFs，这是因为分别作为PCDDs、PCDFs和类二噁英PCBs中主要同系物的1,2,3,7,8 - 五氯二苯并对二噁英、2,3,4,7,8 - 五氯二苯并呋喃和3,3',4,4',5 - 五氯联苯（#126）具有不同程度的降低。此外，在本次跟踪调查中，我们观察到三名女性样本中PCDDs、PCDFs和类二噁英PCBs的浓度显著增加，且三个样本中异构体增加的模式有所不同。据推测，浓度增加主要是由于两次分娩期间的饮食摄入。孕妇保持均衡饮食对于减少婴儿接触这些化学物质很重要。
