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

本研究首次建立了全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，明确了溴系二恶英和溴化阻燃剂在血液、母乳、膳食、食品等方面的污染现状。母乳中溴系二恶英的主要污染源多溴联苯醚（PBDEs）的污染表明，受膳食摄入的短暂影响。这一新知识表明，母乳污染可以通过摄入适当的污染少的食物来减轻。此外，还阐明了溴化阻燃剂、四溴双酚A、三溴苯酚、溴化/氯代二恶英、溴化二恶英等多溴联苯醚类物质在水体中的污染现状与多溴联苯醚类物质的污染现状的差异。另一方面，母乳中的溴化/氯化二恶英与二恶英毒性当量（TEQ）的污染率与人造奶或牛奶相比已进入相当高的状态，显示污染原因可能源自住宅。即使在胃排空期间进行约30分钟的短时间母乳喂养，且进餐的影响很小，母乳中多溴联苯醚的浓度和组成比例也发生了急剧变化。这一结果表明，多溴联苯醚在人体内积累的作用是复杂的。如上所述，本研究获得了一些宝贵的新发现。这些研究结果对今后的人体污染、哺乳污染、环境污染、食品污染等的防治措施具有重要的参考价值。

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.