Overview
- The peer-reviewed PNAS paper modeled dose–response from 10,412 necropsies across 57 seabird species, all seven sea turtle species and 31 marine-mammal species, with plastics detected in 35% of seabirds, 47% of turtles and 12% of marine mammals.
- Seabirds showed extreme sensitivity to rubber, with six pea-sized pieces linked to roughly a 90% chance of death.
- Volume-based thresholds included less than three sugar cubes for a puffin-sized bird and about two baseballs for a loggerhead turtle to reach around 90% mortality.
- For marine mammals, roughly 29 ingested items often proved lethal, with soft plastics and fishing gear posing the highest risks.
- Researchers say the quantified thresholds can inform targeted measures such as curbs on balloons and plastic bags, while emphasizing the analysis excludes chronic toxicity and entanglement and likely understates overall harm.