The ingestion of plastics by animals poses risks to individuals, ecosystems, and human health. While the abundance and size distribution of environmental plastics are increasingly understood, it's unclear which sizes any given animal ingests. This study uses published data to establish an allometric relationship between plastic consumption and animal size, estimating the size distribution of plastics animals can feasibly ingest. Analysis of over 2000 gut content analyses from animals spanning three orders of magnitude in size (9 mm to 10 m) reveals that body length accounts for 42% of the variance in ingested plastic length, indicating an approximate 20:1 size ratio between animal body length and the largest ingested plastic. This work improves global plastic pollution risk assessments by quantifying the link between animals and the plastics they ingest.

Ifan B. Jâms, Fredric M. Windsor, Thomas Poudevigne-Durance, Steve J. Ormerod, Isabelle Durance