David Griffith grew up in Ann Arbor, Mich., and first became excited about sewage in the summer of 2006 while he was collecting water samples for his master’s thesis project from the Hudson River near one of New York City’s largest wastewater treatment plants. Huge sewage discharges that contained lots of contaminants and carbon that appeared quite old based on radiocarbon dating got him wondering about the fate of these sewage-derived contaminants in the ocean. Since entering the MIT/WHOI Joint Program, he has used chemical and isotopic methods to understand the flow of carbon and the behavior of estrogens in coastal ocean ecosystems. When he’s not extracting seawater, he enjoys biking, angling for trout, and playing upright bass in the bluegrass band, Gone To Seed. His mentor on this article was Marguerite Holloway, a contributing editor at Scientific American and the director of science and environmental journalism at the Columbia Graduate School of Journalism.