When David J.X. Gonzalez thinks about the places that have most shaped his life, he remembers the 18-mile stretch of sand dunes bordering his hometown on California's Central Coast.
In the 1990s, the vast Guadalupe-Nipomo Dunes Complex was his playground - a place where he could run down steep hills before collapsing into the soft, sandy earth. There, people fished offshore, hikers watched for hawks and beachcombers scouted for the threatened western snowy plover.
It was also the site of a decadeslong oil spill that nearly destroyed an ecosystem.
Today, Gonzalez is an environmental health scientist and assistant professor at UC Berkeley's School of Public Health, where he studies the legacy of California's oil and gas industry and its effects on human health. Inspired by his childhood experience, his research has influenced policy about the proximity of oil wells to people's homes and sparked conversations about the effects of oil drilling and worsening wildfires on human health.
"We're counting harm," Gonzalez said. "We are counting people that have been harmed by different practices and pollution from certain industries that have created the world that we live in today. I want to transition to a place where we're counting benefits."
At the moment, that future feels far off, Gonzalez said. Federal officials have recently rejected scientific consensus about climate change, gutted regulations governing fossil fuel industries and curtailed programs that monitor environmental and human health.
Gonzalez said it's a hard time to be a public health scientist who studies air pollution, oil and gas development and threats to marginalized communities. But the books lining his office chronicling past fights for justice remind him that progress isn't always linear. By collaborating with communities, quantifying harms has become his responsibility - and also a form of resistance.
"Doing my science is an act of hope," he said, "and an act of love for people that I care about and for the places that I call home."
Pacific Southwest Region USFWS from Sacramento via Wikimedia Commons
'A chance to live a happy, healthy life'
Growing up in the small community of Nipomo in San Luis Obispo County, Gonzalez remembers peering out the window on family drives to the grocery store. Along Highway 101, he saw fields of produce punctuated with oil drilling machines. He thought they looked like dinosaurs.
Gonzalez didn't know then that, for nearly four decades, pipelines owned by the Union Oil Company of California had leaked some 12 million gallons of diluent - a product similar to kerosene that helps crude oil flow. While the Exxon Valdez spill became known around the world, the slow-motion disaster at the Guadalupe-Nipomo Dunes received significantly less attention.
Courtesy of David J.X. Gonzalez
The Silent Spill, as many people called it, would become one of the largest oil spills in U.S. history. Benzene and other volatile compounds leached into the sand dunes and groundwater, contaminating surface wetlands and poisoning the marshes and estuaries inhabited by numerous rare birds and amphibians.
The company responsible for the leak, also known as Unocal, shuttered the site in 1994. In addition to habitat restoration, the company agreed to a $9 million settlement to repair damaged natural resources and provide visitor services in the area. Chevron acquired the company in 2005, continuing the cleanup work.
Gonzalez said the aftermath of the Guadalupe-Nipomo Dunes disaster showed him the importance of regulating polluters and how scientists can - and should - work to protect historically marginalized communities.
His childhood also taught him another formative lesson. Gonzalez suffered from a disease called pseudotumor cerebri, a condition causing debilitating headaches and vertigo that can mimic the effects of a brain tumor. The illness made him miss half of fifth grade and all of sixth grade. While his illness wasn't linked to the spill, he said it dramatically shaped his identity and interests in preventing disease.
"When I think about how I got to where I am today, I think of wanting to make sure that every kid grows up with a chance to live a happy, healthy life," Gonzalez said.
Courtesy of David J.X. Gonzalez
Back to the dunes
In addition to the cleanup, money from the settlement helped finance organizations like the Dunes Center, a museum and conservation nonprofit dedicated to the dunes. Gonzalez's younger sister interned there - work that launched her non-profit career and helped inspire Gonzalez's own path. He returned to the area as a UC Davis undergraduate and joined the local land conservancy, where he helped with habitat monitoring and restoration linked to the spill.
During his graduate work at Yale and Stanford, Gonzalez attended community meetings and met with advocates and lawyers who had direct experience with polluting industries and environmental harms. He also learned of the links between California's oil production, air pollution and adverse birth outcomes. In the 1920s, for example, Southern California produced 20% of the world's oil supply, oil derricks dotted Huntington Beach and fires at drill sites burned near fast-growing subdivisions.
"I don't think you need a Ph.D. in public health to know that that might not be good for you," Gonzalez quipped.
Federal Writers' Project of the Works Progress Administration of Northern California via Wikimedia Commons
Yet today, a century later, there remains a shortage of epidemiological research looking at the industry's effect on human health. It's difficult to study, he said, noting the challenges with isolating the causes of someone's asthma or a rise in premature births. But as he thought of communities like his, he considered how knowledge can be reciprocal - that communities with direct experiences should shape the research, which can ultimately help improve lives.
Brandon Sánchez Mejia/UC Berkeley
Through a multi-year study of air quality and residential experiences of living near wells in Southern California, Gonzalez and a team of researchers concluded that living close to oil wells was linked to preterm birth. Drilling, producing, transporting, processing, refining and burning oil harm public health - and disproportionately affect people living close to those operations, he said.
Findings from the team of health experts became part of the base of evidence in a 2024 report to the state, which advocacy groups and lawmakers used to craft legislation about setback requirements for new oil and gas developments.
"My theory of change," Gonzalez said, "is that we can work alongside communities and back up their knowledge with peer-reviewed science, and bring that evidence to regulators and policymakers."
It's a theory that would serve him well when he came to Berkeley in 2021.
Learning from communities first
Rachel Morello-Frosch, a renowned professor of public health and of environmental science, policy and management at Berkeley, co-chaired that group of experts. She met Gonzalez near the end of his time at Stanford, and she hired him as a postdoctoral fellow at Berkeley for the project looking at community health and oil and gas development.
Courtesy of Lara Schwarz
"I'm grateful to have such an interdisciplinary scholar as my colleague who is now training a new generation of environmental health scientists," Morello-Frosch said. "Not only is David committed to undertaking innovative and high-caliber research, he seeks to translate his scientific work into opportunities for policy change."
It ultimately led him to becoming a member of the Berkeley faculty in 2023. Since arriving at Berkeley, Gonzalez has led research into the compounding effects of worsening wildfire. In 2024, his team found that more than 100,000 oil and gas wells across the western U.S. are in areas burned by wildfires in recent decades. Some 3 million people live next to wells that could soon be in the path of fires worsened by climate change - potentially creating a perfect storm of health harms.
Brandon Sánchez Mejia/UC Berkeley
In his fall course about environmental health equity, he encourages students to interrogate their surroundings and ask questions about pollution in the very places they played as children. To invite fresh perspectives, he opens his lab meetings to all students, regardless of research experience. When he publishes new research, he often translates his findings into Spanish to reach an even broader audience.
That kind of openness and commitment to teaching for the public good encapsulates what Gonzalez is like as a mentor, said Lara Schwarz, a postdoctoral researcher who has worked with him for two years.
"He's very thoughtful about the potential impact of our work as well as the accessibility of doing this research," Schwarz said. "He's also making sure that we're thinking through all the different barriers to getting this information to the public and trying to make it as accessible as possible."
Gonzalez said connecting with students and communities is a core part of his research. For him, first-hand expertise from local meetings and interviews can outweigh lessons from textbooks. The reason, he said, is that those who can help find actionable solutions to a problem are often those who have experience with it.
"For some people, this is something they read about," Gonzalez said. "For others, this is something they live."
