The Department of Public Health Sciences (DPHS) proudly welcomes Dr. Onja Davidson Raoelison as a new Assistant Professor of Environmental Health.

Dr. Raoelison earned her PhD and Master of Science in Environmental Engineering from the University of California, Los Angeles. She also holds a Master of Science in Civil Engineering from École Spéciale des Travaux Publics in France. Before joining DPHS, she completed a postdoctoral fellowship at the Stanford University School of Medicine.

Her path to environmental health began in Madagascar, where she was born and witnessed the serious consequences that limited access to safe water can have on communities. “I saw firsthand how people became sick and even died because of unsafe water,” Dr. Raoelison said. “Because both of my parents are doctors, I hesitated to choose between engineering school and medical school. Then I realized that, instead of trying to heal people who were already sick, I wanted to find solutions that could prevent people from becoming sick. Therefore, I could save lives.”

That goal led Dr. Raoelison to pursue environmental engineering to develop sustainable solutions that protect water quality and, in turn, human health.

Dr. Raoelison’s research examines the intersection of climate change, the environment, and human health, with an emphasis on communities affected by extreme events. Her previous research has focused on wildfires and their effects on water quality in surface and coastal waters, as well as the resulting health consequences for vulnerable communities. “I am so glad to be at DPHS as an Environmental Health professor because my research integrates environmental engineering and medicine,” she said. “When combined, these fields are at the core of environmental health and can help address pressing public health challenges that are being exacerbated by climate change.”

At UH Mānoa, Dr. Raoelison plans to expand this work by investigating how nature-based solutions can mitigate the environmental health effects of extreme events. “As a tropical island, Hawaiʻi receives significant rainfall. Naturally, rain flows through rivers and streams, infiltrates the soil, which acts as a natural filter, and recharges underground aquifers. Groundwater is Hawaiʻi’s most critical natural resource, supplying 99% of domestic water. However, water diversion and widespread paving have disrupted this cycle, transforming what was once a renewable resource into hazardous wastewater during storm events,” she said. 

Her research specifically asks: what was given to Hawaiʻi, what has been lost, and how do we restore it? By combining laboratory and field-based research, she hopes to develop resilient green infrastructure that responds directly to the needs of island communities while respecting and incorporating Native Hawaiian values and practices.

In addition to advancing environmental health research, Dr. Raoelison hopes to help address Hawaiʻi’s need for a stronger Environmental Health workforce through teaching, mentorship, and hands-on student training.

“Native Hawaiians nurture the connection between land wellbeing and human health,” said Dr. Raoelison. “My ambition is to build a new generation of Environmental Health leaders in Hawaiʻi who are able to advocate against health threats related to issues such as climate change and pollution.”

Her research will enhance student learning by providing hands-on opportunities in both laboratory and field settings. Students will contribute to the development of innovative and practical solutions that help communities become more resilient.