DISPOSITION OF HALOGENATED DIBENZOFURANS

卤代二苯并呋喃的处置

• 批准号: 3918602
• 负责人: L S BIRNBAUM
• 金额: --
• 依托单位: NATIONAL INSTITUTE OF ENVIRONMENTAL HEALTH SCIENCES
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/3918602
• 关键词: Pongidae; biotransformation; chemical structure function; detoxification; dioxins; embryo /fetus toxicology; environmental contamination; environmental toxicology; gastrointestinal toxin absorption; halobiphenyl /halotriphenyl compound; halogenation; laboratory rat; occupational hazard; polychlorodibenzofuran; toxicant screening; toxin metabolism

Chlorinated dibenzo-p-dioxins (CDDs) and dibenzofurans (CDFs) are found worldwide as environmental pollutants. They have no known industrial use but are produced during the synthesis and breakdown of other chlorinated organic chemicals. They have been involved in several incidents of human poisoning. Brominated dioxins and furans are also suspected of posing an occupational and environmental hazard. Brominated napthalenes, a related group of compounds, were involved in an incident of human and animal poisoning in the past decade. The degree of halogenation correlates with the toxicity of these compounds, with those congeners possessing less than four halogens being relatively non- toxic. Halogenation in the four lateral positions is required for toxicity which then tends to decrease as the number of halogens increases. Metabolism of these chemicals is a detoxification process. Persistence can result in increasing body burdens upon repeated low dose exposures. While oral absorption is quite good (>70%), dermal absorption tends to be limited. However, as doses are decreased towards the levels which exist in environmental situations, as much as 40-50% of the applied dose may be absorbed through the skin. After a single application, absorption continued for several days at a slow rate. 2,3,7,8-TetraCDF (TCDF), which is metabolized relatively rapidly, was better absorbed than the related compounds, 2,3,4,7,8-pentaCDF, 1,2,3,7,8-pentaCDF, or 2,3,7,8-tetraCDD (TCDD). The disposition of 1,2,3,7,-pentaCDF was examined in male rats. This isomer was distributed throughout the body (liver and adipose were the major tissue depots), and eliminated in the feces with a half-life of 2 days. Metabolism occurred prior to biliary excretion. These results are similar to those obtained with TCDF but are in contrast to those from studies with 2,3,4,7,8-pentaCDF and TCDD which are both poorly metabolized, and therefore persistent.

氯化二苯并对二恶英 (CDD) 和二苯并呋喃 (CDF) 是 作为环境污染物在全世界范围内发现。 他们没有已知的 工业用途，但在合成和分解过程中产生 其他氯化有机化学品。 他们曾经参与过 发生多起人类中毒事件。 溴化二恶英和 呋喃还被怀疑构成职业和 环境危害。 溴化萘，一组相关的 化合物，涉及人类和动物事件 近十年中毒事件。 卤化度 与这些化合物的毒性相关 具有少于四个卤素的同系物相对非 有毒的。 需要在四个横向位置进行卤化 毒性随着卤素数量的增加而降低 增加。 这些化学物质的代谢是解毒 过程。 长期坚持会增加身体负担 重复低剂量暴露。 虽然口服吸收还是不错的 (>70%)，皮肤吸收往往受到限制。 然而，随着剂量 减少到环境中存在的水平 情况下，多达 40-50% 的施用剂量可能被吸收 通过皮肤。 单次涂抹后，持续吸收 以缓慢的速度连续几天。 2,3,7,8-TetraCDF (TCDF)，其中 代谢相对较快，吸收效果更好 相关化合物，2,3,4,7,8-pentaCDF，1,2,3,7,8-pentaCDF，或 2,3,7,8-tetraCDD (TCDD)。 1,2,3,7,-pentaCDF 的处置是 在雄性大鼠中进行了检查。 该异构体分布于 身体（肝脏和脂肪是主要的组织库），以及 随粪便排出，半衰期为2天。 代谢 发生在胆汁排泄之前。 这些结果类似于 通过 TCDF 获得的结果，但与研究结果相反 2,3,4,7,8-pentaCDF 和 TCDD 均代谢不良， 因而坚持不懈。