Young-onset type 2 diabetes (T2D) is a priority public health issue, since it is often unrecognized, responds poorly to treatment, and results in rapid progression of microvascular and macrovascular complications. In this project we are examining how exposure to multiple environmental chemicals may increase susceptibility to T2D in youth. The multidisciplinary team of investigators is testing this hypothesis in a discovery longitudinal cohort of Hispanic adolescents at risk for T2D with existing gold standard clinical assessments of glucose homeostasis, insulin secretion, and β-cell function (the Study of Latino Adolescents at Diabetes Risk, SOLAR), and to replicate findings and examine generalizability in a longitudinal cohort of similar design with a representative sample of Hispanic and non-Hispanic youth (Children Health Study, CHS). In addition, high resolution metabolomics profiles will advance our understanding of the mechanisms underlying the diabetogenic effects of POPs. In both cohorts, we will use novel statistical and bioinformatics methods to predict subgroups of youth at increased risk for T2D based on their exposure to environmental chemicals and metabolomics profiles