Prenatal Timing of Heavy Metal Exposures from Autistic and Non-Autistic Children

描述（由申请人提供）：对自闭症的病因或风险因素知之甚少，自闭症是一种影响美国50名儿童中1名的疾病。虽然遗传和环境因素被认为是共同作用的，但具体机制尚不清楚，并且缺乏在神经发育关键时期对环境风险因素的测量。这项病例对照研究旨在应用一种新的牙齿生物标志物的早期生活金属暴露，包括在子宫内，以确定ASD的危险因素。除了关注曝光强度，我们还将 能够识别病例和对照之间暴露时间的差异。这将使我们能够确定暴露时的关键窗口，即使是低水平，也会增加ASD的风险。使用拟定的生物标志物，我们将直接评估胎儿暴露，而不依赖于母体生物标志物，母体生物标志物可能仅提供胎儿金属暴露的间接测量。这项工作将对早期生命化学物质关系的流行病学调查产生重大影响。 它可以用于客观地重建暴露强度和时间。

DESCRIPTION (provided by applicant): Little is known about the etiology or risk factors for autism, a disease affecting 1 in 50 children in the U.S. While genetic and environmental factors are thought to act together, the specific mechanisms are not known and the measurement of environmental risk factors during critical periods of neurodevelopment has been lacking. This case-control study seeks to apply a novel dental biomarker of early life metal exposure, including in utero, to identify risk factors for ASD. Beyond looking at exposure intensity, we will be able to identify differences in exposure timing between cases and controls. This will allow us to identify critical windows when exposure, even at low levels, increases the risk of ASD. Using the proposed biomarker, we will directly assess fetal exposure, and will not rely on maternal biomarkers which may only provide an indirect measure of fetal exposure to metals. This work will have substantial impact on epidemiologic investigations of the relation of early life chemical exposures to ASD and other neurodevelopmental disorders as it can be used to objectively reconstruct both exposure intensity and timing.