TOXICITY OF METHYL MERCURY IN A FISH EATING POPULATION

甲基汞对食鱼人群的毒性

• 批准号: 6382339
• 负责人: THOMAS W CLARKSON
• 金额: $ 85.46万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 财政年份: 2000
• 资助国家: 美国
• 起止时间: 2000-07-21 至 2005-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6382339
• 关键词: clinical research; developmental neurobiology; developmental nutrition; diet; environmental toxicology; fish; food chain contamination; human subject; mercury; mother /embryo /fetus nutrition; neuroprotectants; nutrition related tag

Methyl mercury is considered to be a developmental neurotoxicant. However, contrary to expected findings, a longitudinal study in the Seychelles has revealed a positive association between increasing mercury levels, measured in maternal hair prenatally and in infant hair, and enhanced child development. Given that fish consumption the Seychelles is high, and that fish intakes correlate with hair mercury levels, we hypothesize that certain micronutrients in fish may be (a) beneficial the child development and (b) protective against the neurotoxic effects of methyl mercury. We propose to test this hypothesis in a new study of 250 mother-infant pairs recruited in the Seychelles during the first trimester and followed longitudinally until the infants reach 29 months of age using the most sensitive developmental endpoints available. The four likely micronutrients, based on their levels in fish and their documented roles in brain development and prioritized in terms of biological plausibility, are the long chain polyunsaturated fatty acids principally docosahexaenoic acid, iodine, iron and the amino acid taurine. Also, selenium may play a role as a modifier of the toxic action of methyl mercury and, as such, will be included with mercury as an independent variable. Mercury in maternal and infant hair will continue to be used as our primary measure of prenatal and post natal exposures. In addition to direct measures of mercury, micronutrient status and selenium levels in biological samples from mother and infant, a diet survey including fish consumption will be made at selected pre- and postnatal stages of this study. These data will allow us to characterize metabolic interrelationship between fish intake and levels of mercury and micronutrients that should further test the plausibility of our hypothesis. This proposed study should break new scientific grounds on the interrelationship between nutrition and toxicology. Specifically, we expect that data emanating from the project to indicate that nutritional variables must be taken into account in any evaluation of the neurotoxicity of methyl mercury when fish is the principal source of human exposure to mercury.

甲基汞被认为是一种发育神经毒物。然而，与预期的结果相反，塞舌尔的一项纵向研究显示，孕妇产前和婴儿头发中汞含量的增加与促进儿童发育之间存在正相关关系。鉴于塞舌尔的鱼消费量很高，而且鱼的摄入量与头发汞含量相关，我们假设鱼中的某些微量营养素可能(A)有益于儿童发育和(B)保护儿童免受甲基汞的神经毒性影响。我们建议在一项新的研究中验证这一假设，该研究在塞舌尔招募了250对母婴，在怀孕的前三个月，使用可用的最敏感的发育终点进行纵向跟踪，直到婴儿达到29个月大。根据鱼类中的含量及其在脑发育中的有据可查的作用和生物可信度，四种可能的微量营养素是长链多不饱和脂肪酸，主要是二十二碳六烯酸、碘、铁和牛磺酸氨基酸。此外，硒可以作为甲基汞毒性作用的修饰剂，因此，将作为独立变量包括在汞中。母亲和婴儿头发中的汞将继续作为我们产前和产后暴露的主要指标。除了直接测量母亲和婴儿的生物样本中的汞、微量营养素状况和硒水平外，还将在这项研究的选定出生前和出生后阶段进行包括鱼类消费在内的饮食调查。这些数据将使我们能够描述鱼类摄入量与汞和微量营养素水平之间的代谢相互关系，这应该会进一步检验我们假设的合理性。这项拟议的研究应该会在营养和毒理学之间的相互关系上开辟新的科学基础。具体而言，我们期望该项目产生的数据表明，在对甲基汞的神经毒性进行任何评估时，必须考虑营养变量，因为鱼类是人类接触汞的主要来源。