Another one bites the plastics.

Area of Science:

• Ecology
• Environmental Science
• Entomology

Background:

• Old-growth forests harbor diverse invertebrates, including saproxylic insects vital for nutrient cycling.
• Plastic pollution is a pervasive threat, with terrestrial impacts largely unexplored.
• Expanded polystyrene (EPS) is a common plastic pollutant with low degradation rates.

Purpose of the Study:

• To investigate the potential of saproxylic cetonid beetle larvae to degrade expanded polystyrene (EPS).
• To quantify the fragmentation of macroplastics into microplastics by these larvae.
• To assess the ingestion, egestion, and external attachment of microplastics to larvae.

Main Methods:

• Field-collected saproxylic cetonid larvae were placed in an EPS box.
• Larvae were observed to fragment the EPS material.
• Post-experiment, larvae and their substrate were analyzed for ingested, egested, and attached microplastics.

Main Results:

• Larvae fragmented the EPS box, producing 3441 microplastic particles.
• Microplastics were found in the larvae's egested substrate.
• An average of 30.7 microplastic particles were observed attached to larval setae.

Conclusions:

• Saproxylic cetonid larvae can fragment macroplastics into microplastics.
• Attached and ingested microplastics may be transported and transferred through food webs.
• Plastic pollution poses a risk to vulnerable species, ecosystem services, and potentially human health.