Investigation of current situation and pollution source of human body contamination for highly toxic bromine system dioxins

本研究首次建立了溴系二恶英和溴系阻燃剂的高精度痕量分析方法。其次，通过这些分析方法，明确了血液、母乳、餐饮、食品等溴系二恶英和溴系阻燃剂的污染现状。溴系二恶英的主要污染源多溴二苯醚(PBDEs)对母乳的污染清楚地表明，食物摄入量的影响是暂时的。这一新知识表明，通过摄入污染较少的适当食物，母乳污染是可以减轻的。此外，还阐明了溴化阻燃剂、四溴双酚A、三溴苯酚、溴化/氯化二恶英、溴化二恶英等多溴联苯醚在初产妇和经产妇的污染实际情况的差异。另一方面，母乳中的溴化/氯化二恶英对二恶英毒性当量(TEQ)的污染率与人造奶或牛奶相比已进入相当高的状态，表明污染的原因可能来自住宅。即使在空腹期哺乳30分钟左右，母乳中多溴二苯醚的浓度和组成比也发生了很大的变化。这一结果表明，多溴二苯醚在人体内积累的作用是复杂的。如上所述，这项研究获得了一些宝贵的新发现。可以肯定的是，这些结果可以极大地促进针对未来人体污染、哺乳污染、环境污染、食品污染等的缓解措施。

In this research, the high precision trace analytical methods for all the bromine system dioxins and brominated flame retardants were first developed. Next, by using these analytical methods, the current pollution situation of bromine system dioxins and brominated flame retardants was clearly clarified about blood, breast milk, a meal, food, etc. The pollution of breast milk by the polybrominated diphenyl ethers (PBDEs) which are the main pollution sources of bromine system dioxins showed clearly that the transient influence by dietary intake was received. This new knowledge suggests that pollution of breast milk is mitigable by taking in suitable food stuffs with little contamination. In addition, the difference of the pollution actual condition in primiparae and multiparae was clarified about PBDEs of brominated flame retardants, tetrabromobisphenol A, tribromophenol, brominated/chlorinated dioxins, and brominated dioxins. On the other hand, the pollution rate of the brominated/chlorinated dioxins which occupies breast milk to dioxin toxicity equivalency quantity (TEQ) compared with artificial milk or milk had changed into the quite high state, showing a possibility that the cause of pollution originated in a dwelling. Even at breast-feeding of a short time for about 30 minutes in stomach empty period with little influence of a meal, the concentration and the composition ratio of PBDEs in mother's milk were changed sharply. This result suggests the complicated action of PBDEs accumulated into a human body. As mentioned above, some precious new findings were able to obtain in this research. It is sure that these results can greatly contribute to the measure against mitigation to future human body contamination, suckling contamination, environmental pollution, food contamination, etc.