Microplastic contamination in benthic organisms from the Arctic and sub-Arctic regions

Area of Science:

• Marine Biology
• Environmental Science
• Ecotoxicology

Background:

• The seafloor is a significant sink for microplastics (MPs).
• Limited data exists on MP contamination in Arctic and sub-Arctic benthic organisms.
• Understanding MP presence in these remote ecosystems is crucial for assessing ecological risks.

Purpose of the Study:

• To provide the first data on microplastic abundances and characteristics in benthic organisms from the Bering and Chukchi Seas.
• To identify dominant MP types, compositions, and sizes in these organisms.
• To explore potential transport mechanisms and trophic transfer of MPs in the Arctic benthic environment.

Main Methods:

• Analysis of microplastics in 413 dominant benthic organisms from 11 species.
• Quantification of microplastic abundance (items g⁻¹ wet weight and items individual⁻¹).
• Characterization of microplastics by type (fiber, film), color, composition (polyamide, polyethylene, etc.), and size.

Main Results:

• Mean microplastic abundances ranged from 0.02 to 0.46 items g⁻¹ ww or 0.04-1.67 items individual⁻¹, lower than global averages.
• The northernmost site showed the highest microplastic concentrations, indicating sea ice and cold currents as potential transport mediums.
• Fibers (87%) were the dominant type, primarily red and transparent, with polyamide (46%) as the main composition. Predator species showed higher MP ingestion, suggesting trophic transfer.

Conclusions:

• This study presents the initial assessment of microplastic contamination in Arctic benthic organisms.
• Trophic transfer may play a significant role in microplastic accumulation within Arctic benthic food webs.
• Further research is needed on temporal trends and the ecological impacts of microplastics on Arctic benthic fauna.