Yoshira ‘Yoshi’ Ornelas Van Horne, Ph.D. – Putting Communities at the Center of Exposure Science Research Skip Navigation
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Your Environment. Your Health.

Yoshira ‘Yoshi’ Ornelas Van Horne, Ph.D. – Putting Communities at the Center of Exposure Science Research

August 23, 2022

Yoshira ‘Yoshi’ Ornelas Van Horne, Ph.D.
Ornelas Van Horne joined the department of environmental health sciences at Columbia University in August 2022.

Every data point is a person, and every person deserves respect and answers. That philosophy guides Yoshira "Yoshi" Ornelas Van Horne, Ph.D., who studies what chemicals people are exposed to in the environment and how those exposures occur. She says the field of exposure science has not always taken a community-centered approach to research – and she wants to change that.

“To fully characterize people’s exposures, you have to work with and listen to communities to understand their stories and lived experiences,” said Ornelas Van Horne, an assistant professor at Columbia University.

It was through her graduate and postdoctoral research on two NIEHS-funded projects – one working with Diné (Navajo) communities, the other with Latino children and their families – that she came to recognize the importance of including community perspectives in exposure science research.

Water Is Life

Ornelas Van Horne first saw the benefits of a community-based approach during her doctoral research at the University of Arizona. With her advisors, Paloma Beamer, Ph.D., and Karletta Chief, Ph.D., she worked on an NIEHS-funded project to understand exposure risks for Diné communities following the 2015 Gold King Mine spill, which sent 3 million gallons of polluted water into the San Juan River.

Yoshira ‘Yoshi’ Ornelas Van Horne, Ph.D. leading a seminar on water sampling
Ornelas Van Horne, left, leading a water sampling seminar with Diné college students and Navajo Nation community health representatives. (Photo courtesy of Rietta Wagoner).

“For the Diné, water is life,” she explained. “The river supports their livelihood and is essential for many cultural and spiritual activities.”

The spill demanded a risk assessment, an evaluation of how the polluted water may harm human health and the environment. However, that assessment was based on the needs of outdoor recreationalists and did not consider how Diné communities interact with the river and how those interactions can affect health, according to Ornelas Van Horne.

To help address Indigenous community health concerns, Ornelas Van Horne collaborated with Diné students, researchers, and community health representatives.

Yoshi Ornelas Van Horne and Mariah Paul sampling water
Ornelas Van Horne, left, and Mariah Paul conduct water sampling on the San Juan River. Photo courtesy of Rietta Wagoner).

Through focus groups and surveys designed with community members, the team identified 43 distinct ways in which the Diné rely on the San Juan River for their livelihood, diet, recreational, cultural, spiritual, and arts and crafts activities.

“Excluding these activities from the risk assessment process can result an underestimation of exposures for the Diné people,” she said.

Ornelas Van Horne and her Diné research partners shared their results through culturally appropriate materials. Their approach included:

Agent of Change

In 2019, Ornelas Van Horne became the first Latina to receive a Ph.D. from the environmental health sciences department at the University of Arizona.

“Part of me is really proud, but the other part recognizes that academia has a long way to go — and that builds a fire in me to connect with and mentor young researchers from historically underrepresented backgrounds in the sciences,” she said.

She is doing just that through her work with Agents of Change for Environmental Justice, an organization focused on increasing diversity in science and nurturing the next generation of environmental justice leaders.

“Agents of Change gives early career researchers a safe and inclusive space to connect while learning how to use science communication to amplify their work,” she said.

As an Agents of Change fellow, Ornelas Van Horne participated in a podcast and wrote a personal essay describing her journey in environmental health and the importance of centering research on communities. She now serves as assistant director of the organization.

Agents of Change was founded by Ami Zota, Ph.D., and is administered through the environmental health sciences department at the Columbia University Mailman School of Public Health. Environmental Health News is a key program partner.

  • Creating print materials that were individually delivered to participants.
  • A series of videos narrated in Navajo.
  • Hosting meetings in Navajo Chapter houses, a familiar and important space for participants.
  • Ensuring a Diné translator was present at all meetings.
  • Respecting Indigenous data sovereignty, or the right of the Diné to govern how study data is collected, who owns it, and how it can be used.

Importantly, the research team disseminated Diné-specific water use guidelines for crop irrigation and livestock purposes — two of the main ways participants reported interacting with the river. The guidelines help Diné communities make informed decisions about river-based farming practices and allow them to continue passing cultural farming traditions down to younger generations.

The Reason Behind the Research

Ornelas Van Horne said that working with the Diné community was one of the biggest “aha!” moments of her career.

“I just knew that this was it, that this is how we move science forward — by partnering with communities to answer their questions. From that point on, I knew I only wanted to do research if it involved and benefited communities,” she said.

That revelation spurred her to take a postdoctoral position at the University of Southern California where she worked with Latino families in the agricultural community of Imperial Valley, California. Supported by a diversity supplement from NIEHS, she aimed to address community concerns about pesticide exposure and children’s respiratory health.

“Many schools and homes in Imperial Valley are located near agricultural fields sprayed with pesticides. Parents are worried that exposure to these pesticides may contribute to asthma in their children,” said Ornelas Van Horne, who noted that the area has some of the highest child asthma rates in the state and nationally.

Yoshi Ornelas Van Horne and CCV community partner checking air pollution monitors
Ornelas Van Horne, kneeling, and CCV community partner checked on air pollution monitors as part of the AIRE study. (Photo courtesy of Dayane Duenas Barahona).

To shed light on this association, she is using data from the NIEHS-funded Assessing Imperial Valley Respiratory Health and the Environment (AIRE) study. Co-led by Shohreh Farzan, Ph.D., and Jill Johnston, Ph.D., AIRE researchers are assessing how dust from the drying Salton Sea, pesticides, and other air pollutants affect respiratory health in more than 500 elementary school-age children.

“None of this would be possible without our community partner, Comité Cívico Del Valle, and the Imperial Valley families and children, who are so willing to participate in the AIRE study in hopes of a healthier community,” she said.

Her research is ongoing, but preliminary findings suggest a link between pesticide applications, especially sulfur, and an increased risk of wheezing in children.

Roadmap for Redefining Exposure Science

To help other exposure scientists take a community-centered approach, Ornelas Van Horne and collaborators developed a framework. Grounded in the principles of environmental justice, the framework encourages researchers to move beyond simply characterizing harmful exposures to identifying and implementing solutions for communities — especially those dealing with high levels of pollution.

For those scientists, Ornelas Van Horne offers this advice: “Let go of your assumptions and take time to listen. You can learn a lot from community members and that local knowledge will help strengthen your science and generate community-driven solutions.”

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