Erin Murphy, an alumna of the University of Illinois, School of Integrative Biology (B.S., 2013), and Earth Science and Environmental Change (M.S., 2015), has been at the forefront of marine conservation through her leadership role at Ocean Conservancy. As the manager of a study published in 2025, Murphy and her team revealed that small amounts of plastic can be lethal to ocean animals, highlighting the widespread and alarming reach of plastic pollution in marine ecosystems.
The comprehensive study analyzed data collected over decades from global sources, documenting plastic ingestion in species focusing on seabirds, sea turtles, and marine mammals to identify lethal thresholds for these groups. For example, just 6 pieces of rubber, each smaller than a size of a pea, are enough to kill 90 percent of seabirds. This research underscores the pervasive threat plastics pose to ocean health, affecting biodiversity, food webs, and ultimately human health through seafood consumption.
“We’ve long known that ocean creatures of all shapes and sizes are eating plastics; what we set out to understand was how much is too much,” said Murphy. “The lethal dose varies based on the species, the animal’s size, the type of plastic it’s consuming, and other factors, but overall it’s much smaller than you might think, which is troubling when you consider that more than a garbage truck’s worth of plastics enters the ocean every minute.”