Examining a Novel Gastrointestinal Intervention to Negate Environmental Toxicants (ENGINE)

Inclusion Criteria: * Male firefighter * California resident * Age 18-64 * Full-time, active-duty (fire suppression and/or arson investigation) * English-speaking * Access to a reliable internet connection * Willing to attend 3 in-person study visits in the San Francisco Bay Area over about 6.5 months * Willing to receive weekly text message reminders to complete online surveys * Willing to complete a mail-based, at-home finger-prick blood test * Willing to take 3 tablets (each tablet about the size of a multivitamin) orally twice daily for a total of 6 months * Evaluated by study team to have an elevated risk of PFAS exposure (e.g., duration of firefighting service, prior NASEM-7 result greater than or equal to 10) Exclusion Criteria: * Gastroparesis or other severe gastrointestinal motility disorders * Bowel obstruction * History of major gastrointestinal tract surgery * Dysphagia or difficulty swallowing (due to tablet size) * History of hypertriglyceridemia (triglycerides exceeding 500 mg/dL) * History of hypertriglyceridemia-induced pancreatitis * Type 1 or 2 diabetes * History of fat-soluble vitamin deficiencies i.e., vitamins A, D, E, or K * Phenylketonuria * History of known bleeding/clotting disorders * Medications or treatments that may impact the excretion of PFAS, such as activated charcoal, other bile acid sequestrants, chelation therapies, etc. * More than one blood or plasma donation in the past 12 months and/or unalterable plans to donate blood or plasma during the study participation period * Use of clomiphene, testosterone, human chorionic gonadotropin, anabolic steroids, anastrozole or any other substances that may impact testosterone levels in males