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

Sea-surface retention effect shapes ocean microplastic fibers

Physical Review Research 2026

Summary

Scientists found that longer plastic microfibers tend to get "trapped" right at the ocean's surface, in a thin film called the sea-surface microlayer, rather than sinking or spreading evenly through the water, likely because they get physically pinned there. This matters because that surface layer is where a lot of marine life feeds and where air meets sea, so understanding which microplastic fibers linger there helps researchers figure out how these pollutants might enter the food chain and eventually reach us.

Study Type Environmental

Microfibers contaminate the global ocean, but their impact depends on length-dependent residence at the air-sea interface. In the submillimeter range, the sea surface exhibits a surface-enrichment signature: The long-to-short fiber ratio is higher at the interface than a few meters below (about 5 m), meaning that longer fibers are relatively more represented at the surface, despite an approximately length-flat fragment production expected below the fiber breakage cutoff. We show that this contrast is consistent with length-selective retention in the sea-surface microlayer via capillary pinning and attachment to sparse anchoring sites. A minimal two-state mixed-layer column model yields an approximately linear surface enrichment, reproduces the observed surface-subsurface contrast, and identifies the microlayer as a dynamic reservoir shaping residence times, exposure, and air-sea exchange of fiberlike pollutants.

Share this paper