Watch an Environmental Health Professor Explain Wastewater Woes

What happens to human and animal waste once it's flushed away? UC Berkeley professor Jay Graham says the answer is more important than you may think.

Few of us think about what happens to our waste after we flush the toilet, but to Jay Graham, its path is a critical part of improving human health.

Graham is a professor of environmental health at UC Berkeley’s School of Public Health. While most of us don’t give a flush a second thought, it’s what drives much of his professional life. As he puts it succinctly in this 101 in 101 video, “I study poop!”

His work has ranged from studying the effects of greater access to public toilets in San Francisco, particularly for the unhoused, to understanding how untreated wastewater from livestock contaminates fruits and vegetables with fecal matter, leading to outbreaks and recalls across the U.S.

As he explains, his interest in waste was spurred by learning that much of the earth’s population doesn’t have access to basic sanitation and clean drinking water — and even those who do are still often flushing their untreated wastewater into the environment, where it can lead to disease.

Graham has also been studying how human and livestock waste affect the environment and health in less-resourced parts of the world. His research has taken him to sub-Saharan Africa, to informal housing along the US-Mexican border in Juarez, and to Ecuador, where he’s been researching antimicrobial resistance caused by poultry waste. 

“In my work, we identify the problem and break it down into its various parts,” explains Graham. “And then we look for solutions and also analyze the impact that those solutions will have.”

Watch more 101 in 101 videos featuring UC Berkeley faculty and experts here.