Human Exposure To Halogenated Aromatic Compounds

人类接触卤化芳香族化合物

• 批准号: 6534998
• 负责人: WALTER ROGAN
• 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/6534998
• 关键词: Mexico; Taiwan; United States; child behavior disorders; child mental disorders; child physical development; clinical research; cooperative study; dichlorodiphenyltrichloroethane; embryo /fetus toxicology; environmental contamination; environmental exposure; environmental toxicology; epidemiology; halobiphenyl /halotriphenyl compound; human milk; human puberty; human subject; lactation; longitudinal human study; malaria; menstrual cycle; pesticide biological effect; placental transfer; prenatal stress

Aims: PCBs and similar compounds are a worldwide pollution problem, and appear with high prevalence in human tissue. For many years we have been studying the consequences for child development of exposure to these compounds, at obviously toxic levels in a food poisoning incident in Taiwan, at relatively high agricultural exposures in rural Mexico, and at background levels in the US. This year, only the Yucheng, or oil disease, study of poisoned persons from Taiwan produced new analyses, although we have used the data from the Mexico study to inform the new, worldwide debate on the use of DDT to combat the resurgence of malaria. Procedures and techniques: In a separate study, we examined and then followed children who were born to mothers poisoned by PCBs and the highly toxic polychlorinated dibenzofurans in the 1979 "Yucheng" incident. We have also followed the adults. We hypothesized that, in 1995, the children would continue to be affected by their prenatal exposure to PCBs/PCDFs as they were in 1991-1992. We hypothesized that the adults would report higher rates of problems known to be associated with PCBs, like acne, but we also hypothesized that the women would report increased menstrual flow and perhaps dyspareunia, because of the primate model of dioxin toxicity showing endometriosis from long term, low level exposure. Accomplishments: In Taiwan, we have been following about 117 children who had transplacental exposure to high doses of PCBs and related compounds. Beginning in 1985, we have documented that the children who were born between 1979 when the poisoning occurred and 1985 have ectodermal defects, developmental delay, and a behavior disorder. This year, for the first time, we were able to show that, by 1995, the reported behavioral abnormalities in the children were diminishing, although their developmental delay remained fixed. This has implications for the study of how PCBs affect the brain, since in previous data the cognitive and behavioral abnormalities occurred together, making it difficult to tell whether they occurred through the same or different mechanisms. A paper describing this work is submitted. We did a survey of the general health of the adults who were poisoned in Taiwan, some of whom were the mothers of the children we have been studying. Since these compounds are very toxic to the female reproductive system when studied in monkeys, we were very interested to find the mild disturbance of menstrual function seen among the older women, with only minor differences in menstrual flow reported, and no change in reported dysmennorhea, fertility, family size, or libido. Those who advocate the use of DDT for malaria control claim that little or no morbidity results from its use. We claim that shortened duration of lactation, which we have observed in association with DDE exposure in North Carolina and Mexico, might result in increased infant mortality in the same regions where it would be most logical to spray for malaria, since poverty and infection rates are high there. The question of how best to control malaria and how to study the consequences of the tactics used will be an active area for the next several years, since 25 countries have gotten exemption s from the world wide ban on DDT to use it to kill mosquitoes.

目的：多氯联苯及其类似化合物是一个世界性的污染问题，并出现在人体组织中的高患病率。多年来，我们一直在研究暴露于这些化合物对儿童发育的影响，在台湾的食物中毒事件中，这些化合物处于明显的毒性水平，在墨西哥农村相对较高的农业暴露水平，以及在美国的背景水平。今年，只有针对台湾中毒者的“禹城”（即油病）研究得出了新的分析结果，尽管我们使用了墨西哥研究的数据，为世界范围内关于使用滴滴涕防治疟疾死灰复燃的新辩论提供了信息。程序和技术：在另一项研究中，我们检查并跟踪了1979年“禹城”事件中被多氯联苯和剧毒多氯二苯并呋喃中毒的母亲所生的孩子。我们也跟着大人。我们假设，在1995年，儿童将继续受到影响，他们的产前接触多氯联苯/多氯二苯并呋喃，因为他们在1991-1992年。我们假设成年人会报告与多氯联苯相关的问题，如痤疮，但我们也假设女性会报告月经量增加，可能是性交困难，因为长期低水平暴露的二恶英毒性灵长类动物模型显示子宫内膜异位症。成果：在台湾，我们一直在跟踪约117名经胎盘接触高剂量多氯联苯和相关化合物的儿童。从1985年开始，我们已经记录了在1979年中毒事件发生到1985年之间出生的儿童有外胚层缺陷，发育迟缓和行为障碍。今年，我们第一次能够证明，到1995年，报告的儿童行为异常正在减少，尽管他们的发育迟缓仍然固定。这对研究多氯联苯如何影响大脑有影响，因为在以前的数据中，认知和行为异常是一起发生的，因此很难判断它们是通过相同还是不同的机制发生的。提交了一份介绍这项工作的文件。我们对台湾中毒的成年人的一般健康状况进行了调查，其中一些人是我们研究的孩子的母亲。由于这些化合物在对猴子进行研究时对雌性生殖系统具有很强的毒性，因此我们非常感兴趣地发现，在老年女性中观察到月经功能的轻度紊乱，仅报告了月经量的微小差异，并且报告的痛经、生育力、家庭规模或性欲没有变化。主张使用滴滴涕控制疟疾的人声称，使用滴滴涕很少或根本不造成发病。我们认为，我们在北卡罗来纳州和墨西哥观察到的与DDE接触有关的哺乳期缩短可能会导致婴儿死亡率增加，而在这些地区，由于贫困和感染率较高，因此最合理的是喷洒疟疾。如何最好地控制疟疾以及如何研究所用策略的后果将是今后几年的一个活跃领域，因为有25个国家已获得豁免，不受世界范围内禁止使用滴滴涕来杀灭蚊子的禁令的约束。