Ultralow Dose PAH Binary Mixture Study

Inclusion Criteria: * Age 21-65 (inclusive) * If female, must be post-menopausal or have had surgical sterilization to eliminate any possibility for fetal exposure * Willing to defer blood donation for one month before, throughout, and one month after completion of study activities * Willing to avoid consuming cruciferous vegetables, I3C or DIM supplements, smoked or cured meat or cheeses, or charcoal-grilled meats for 2 weeks prior to and during each study cycle (gas grilled foods acceptable) Exclusion Criteria: * Smoker (tobacco or other substances) or use of smokeless tobacco in past 3 months or living with smoker * Regular use of medications that affect gut motility or nutrient absorption (e.g. cholestyramine, sucralfate, orlistat, pro- or anti-motility agents) * History of gastrointestinal surgery (e.g. bariatric surgery, cholecystectomy) or gastrointestinal disorder (Crohn's disease, celiac disease, IBS, or colitis) * Current or history of kidney or liver disease * Prior high-dose 14C exposure from medical tests. (micro-dose 14C exposure not exclusionary) * Occupational PAH exposure (e.g. roofers, asphalt pavers, fire-fighters, etc.) * Regular use of indole-3-carbinol or DIM dietary supplements