Greg Zarus is a lifelong scientist and experience community leader, including smalltown mayor, university lecturer, and federal agency office director. He was a career federal scientist at the Agency for Toxic Substances and Disease Registry (ATSDR), the Centers for Disease Control and Prevention (CDC), and as consultant to the Environmental Protection Agency (EPA), the Department of Defense (DoD), Federal Bureau of Investigation (FBI). He has instructed at the US Coast Guard and at several universities. And continues to serve as adjunct faculty or graduate student advisor. Throughout his distinguished career, Greg has managed government programs evaluating chemical exposures associated with the Department of Defense and industrial facilities. He has worked in partnership with 18 federal agencies and 24 state and local organizations, leading investigations and HazMat response efforts that protect communities nationwide. His research contributions include groundbreaking work on microplastics and human health, landfill air quality assessments, and chemical exposure evaluations. Greg continues to translate complex scientific findings into actionable public health guidance through Our1World.