USTUR Scientific Advisory Committee chair, Roger McClellan, discussed the history of radiation and chemicals at Hanford and how science informs public policy during the Spring 2019 Herbert M. Parker Lecture Series. Dr. McClellan gave two lectures that were open to the public, and one that was open only to students. Dr. McClellan is an internationally recognized authority in the fields of inhalation toxicology, aerosol science and human health risk analysis. He is currently an adviser to public and private organizations on inhalation toxicology and human health risk issues. The Parker Lecture Series was sponsored by the Herbert M. Parker Foundation in partnership with WSU Tri-Cities.