0
Article ? AI-assigned paper type based on the abstract. Classification may not be perfect — flag errors using the feedback button. Tier 2 ? Original research — experimental, observational, or case-control study. Direct primary evidence. Sign in to save

Recommendation: Transfer quantification and surface changes of microplastics along the earthworm-chicken food chain — R1/PR7

Original title: Recommendation: Transfer quantification and surface changes of microplastics along the earthworm-chicken food chain — R1/PR7

2026
Jie Yang, Li Xiang, Lianzhen Li, Chen Tu, Yi Luo

Summary

Scientists tracked tiny plastic particles as they moved from soil to earthworms to chickens, finding that the plastic gets broken into smaller and smaller pieces along the way—especially inside the chicken's gizzard, which acts like a grinder. This matters because chicken is a major food source worldwide, and this research shows how plastic pollution can travel through the food we eat, getting more fragmented (and potentially easier to absorb into the body) at each step of the chain.

Polymers
Body Systems

Microplastic (MP) pollution in terrestrial ecosystems is attracting global attention. The transfer of MPs in terrestrial food chains remains poorly understood, particularly in poultry systems. This study investigates polystyrene (PS) MP transfer and surface weathering characteristics in an “earthworm-chicken” food chain by feeding chickens earthworms that had been previously exposed to PS MPs and by oral gavage. The results showed that MP concentrations decreased from soil (10.06 ± 0.03 mg/g) to earthworm casts (6.39 ± 1.05 mg/g) to chicken faeces (3.76 ± 0.39 mg/g), and the transfer process of MPs in the “earthworm-chicken” food chains is characterized by continuous fragmentation. MPs were distributed throughout different parts of the chickens’ digestive tract after 3 h oral gavage and were only detected in the faeces after 24 h. Scanning electron microscopy and Fourier transform infrared spectroscopy revealed that MPs underwent varying degrees of weathering in the earthworm casts, chicken faeces and gastrointestinal tract, exhibiting surface holes and cracks. Compared with pristine MPs, the significantly higher carbonyl index of MPs in the gizzard demonstrates the key role of the gizzard in MP fragmentation. This study contributes to understanding the trophic transfer and fragmentation processes of MPs in chickens, and provides a basis for future research on the environmental processes of MPs in terrestrial food chains.

Share this paper