Project Summary This project seeks to examine the role of the exposome as a significant risk factor for Alzheimer's disease (AD) among non-Hispanic whites, African Americans and Mexican Americans. This work will utilize blood samples from the 3,000 participants in the ongoing Health & Aging Brain Study – Health Disparities study (NIA, U19AG078109). This work can lead to strategies to lower environmental exposures in at-risk populations in order to reduce their risk for developing AD.