I am reminded of the wisdom and kind words shared with me by an elder: Medicine allows you to treat, psychiatry provides the space to heal, and education will let you share. Jonathan Credo, M.D., Ph.D.
From the Navajo Nation to the Lab: A Scientist Who Answers to His Community
Dr. Credo brings chemistry, medicine, and Indigenous values together to tackle the environmental health crises affecting Native American communities.
As a Diné (Navajo)-Filipino scientist, Jonathan Credo, M.D., Ph.D. already felt connected to the land where environmental threats facing the Native community weren't just abstractions. Unregulated water sources laced with uranium and arsenic. Air quality shaped by decades of industrial activity. Health disparities with deep roots and few resources to address them. Today, as a classically trained environmental analytical chemist and physician, Dr. Credo has spent his career turning those lived realities into research communities can use.
Dr. Credo holds dual bachelor's degrees in Biomedical Sciences and Chemistry from Northern Arizona University, a Ph.D. in Clinical Translational Sciences and an M.D. from the University of Arizona, and currently serves as an Internal Medicine-Psychiatry resident at UC Davis. But his credentials only tell part of his story. What sets his work apart is the philosophy underneath it: That communities affected by environmental health problems should be at the table from the very beginning helping to shape the questions, guide the research, and ultimately own the results.
That philosophy has produced real outcomes. In a recent EPA-funded project with a federally recognized southern Arizona tribe, Dr. Credo and his collaborators didn't just measure how local air quality was affecting schoolchildren, they built workshops with Tribal educators and leaders, developed educational materials grounded in the community's own context, and helped the tribe establish its own independent air quality monitoring program, securing additional federal and state funding to sustain it long after the grant period ended.
“Dr. Credo’s research program is explicitly translational," says Timothy E. Albertson, M.D., Ph.D., Chair of the Department of Internal Medicine at UC Davis. "He has developed community-driven projects that integrate rigorous exposure assessment with culturally appropriate interventions. His work on air monitoring and HEPA-based mitigation strategies in school settings directly contributed to the establishment of a tribal-led monitoring network, demonstrating the impact of his research beyond the academic sphere.”
Earlier projects quantified elemental contaminants like uranium and arsenic in unregulated water sources across the western Navajo Nation, investigated environmental exposures along the Colorado River affecting Indigenous and rural communities, and explored the potential links between legacy mining and kidney cancer in Navajo communities. Across all of it, Dr. Credo has experienced something the field doesn't always reckon with directly: data sovereignty — the principle that Tribal communities have the right to control, interpret, and decide what happens to data collected on their lands and about their people.
Dr. Credo also weaves the cultural and traditional teachings of communities into how that work is conducted. Findings are shared back with communities in large, coordinated gatherings, and not just in journal articles. Traditional knowledge holders and community leaders are invited to guide how results are communicated. The research process, from first conversation to final dissemination, is structured around respect.
The impact of that approach extends beyond any single project. Dr. Credo has mentored more than 40 students and early-career scientists, spanning high school through assistant professor level, many from rural and Native American backgrounds. Mentees have gone on to graduate theses, doctoral dissertations, and careers of their own in science. He has received recognition from the National Institutes of Health, the U.S. Public Health Service, and the broader research community, and his work has drawn attention from policymakers at the local, Tribal, state, and national levels.
Dr. Credo's work is a model for what environmental health research can look like when it is built on trust, accountability, and the understanding that the communities most affected by environmental harm deserve science that works for them.
Novel Air Quality Surveillance to Optimize Clinical Interventions for Health Improvement in Rural Four Corners Communities
The Navajo Nation is the largest contiguous federally recognized tribe in the United States — yet across its 72,000 km² territory, consistent air quality monitoring is virtually nonexistent. Decades of uranium, oil, and natural gas extraction in an arid, wind-prone landscape have created serious and ongoing health risks for Four Corners communities, with little data to document them and limited training for the healthcare providers who serve those communities.
Dr. Credo's EHSC Scholar project addresses that gap directly. Working in partnership with three Navajo Nation communities, his team will deploy low-cost air quality sensors to track particulate matter and build the first meaningful baseline of air quality data in these regions. Crucially, the project is community-led: sensors are designed to be accessible and easy to understand, and the work includes developing culturally grounded curricula and workshops with local schools and Tribal educators.
The data collected cannot be used to enforce federal clean air standards — but that's not the point. This project is about putting actionable information in the hands of the people most affected, establishing UC Davis as a committed academic partner, and laying the foundation for larger-scale interventions to come.
