Description:Untargeted analysis of plasma from repeated samples from the USDoD in a study of Inflammatory Bowel Disease. Serum samples from 6-10 years, 4 years, 2 years, and within 1+- years of a Crohn's diagnoses, Ulcerative Colitis, or matched controls were analyzed with GC-HRMS. Associations between the chemical mixture and IBD were tested.