ASU alum contributes to Cozzarelli Prize-winning research on ocean plastics

Erin Murphy, an Arizona State University alum and adjunct professor in the School of Life Sciences, is part of the team behind a 2025 research paper that has been awarded the prestigious Cozzarelli Prize for scientific excellence from the Proceedings of the National Academy of Sciences.

The Cozzarelli Prize, awarded in April, recognizes the most outstanding scientific papers published in PNAS each year, placing the study among the top contributions in applied biological and environmental sciences. Murphy, now manager of ocean plastics research at Ocean Conservancy, contributed to the award-winning work as part of a broader team of scientists studying the impacts of plastic pollution on marine life.

Murphy earned her PhD in biology and society from ASU in 2023, where she studied in the ecology, economics and ethics of the environment track under professors Leah Gerber and Beth Polidoro. Her doctoral research laid the groundwork for the study, which addresses a critical and previously unanswered question: How much plastic does it take to kill marine animals?

While scientists have long known that marine animals ingest plastic, the study is among the first to quantify how much is actually lethal. Drawing on thousands of necropsies from around the world, the research team modeled the relationship between plastic ingestion and mortality across seabirds, sea turtles and marine mammals.

“What we didn’t really understand as a community is how much plastic is too much,” Murphy said.

The findings show that very small amounts of plastic can be deadly, far less than previously assumed. The research also reveals that risk varies by both species and material type. Rubber items like balloons are especially dangerous for seabirds because they are more likely to become lodged in the digestive tract, while marine mammals are particularly vulnerable to soft plastics such as bags. Sea turtles face risks from both hard and soft plastics.

The study adds urgency to a growing global concern: plastic pollution is not only widespread, but its impacts may be more severe than previously understood.

Murphy’s work reflects the interdisciplinary approach she developed at ASU, combining ecological science with policy-relevant research. Her interest in the field stems from a broader focus on how human activity shapes the natural world and how those effects feed back into society.

Before beginning her PhD, Murphy worked as a fellow at the Environmental Protection Agency, where she saw firsthand how scientific research informs environmental decision-making. That experience shaped her focus on producing research that can guide policy and management strategies.

At Ocean Conservancy, she continues that work by contributing to research, policy initiatives and public education efforts aimed at reducing plastic pollution worldwide.

Plastic pollution continues to pose a growing threat to marine ecosystems, affecting wildlife through ingestion, entanglement and chemical exposure. The study also highlights the disproportionate impact on vulnerable species, with many of the affected animals already at risk of extinction.

Murphy emphasized that addressing the issue requires a combination of prevention, improved waste management and cleanup efforts. Because even small amounts of plastic can be lethal, removing debris from local environments can have a meaningful impact on wildlife.

“The flip side of this research showing that small amounts can be lethal shows that, in local areas, cleanups can be really important,” she said.

Building on the findings, Murphy is now helping lead an international working group to expand plastic risk assessment models. The next phase of research will focus on linking environmental exposure to risk for marine species, helping scientists and policymakers better understand how plastic pollution translates into real-world impacts.