Microplastics in Taihu Lake, China.

Area of Science:

• Environmental Science
• Ecotoxicology
• Aquatic Ecology

Background:

• Microplastic pollution in freshwater ecosystems is less understood than in marine environments.
• Taihu Lake is China's third-largest lake and is situated in a highly developed region, making it a critical site for studying pollution impacts.

Purpose of the Study:

• To investigate the levels and characteristics of microplastic pollution in Taihu Lake during 2015.
• To compare microplastic contamination across different environmental compartments (water, sediment, biota).

Main Methods:

• Collected plankton net samples, surface water, sediment, and Asian clams (Corbicula fluminea) from Taihu Lake in 2015.
• Quantified microplastic abundance, size, and composition in collected samples.
• Analyzed spatial distribution of microplastics and correlated with environmental indicators like chlorophyll-α and total phosphorus.

Main Results:

• Microplastic abundance varied significantly, with plankton net samples reaching 0.01×10^6-6.8×10^6 items/km², surface water 3.4-25.8 items/L, sediments 11.0-234.6 items/kg dw, and clams 0.2-12.5 items/g ww.
• Highest microplastic concentrations were found in plankton net samples (southeast) and sediments (northwest).
• Fibers were the dominant microplastic type (100-1000 μm), primarily composed of cellophane. Microplastic levels in clams showed a negative correlation with sediment microplastic levels.

Conclusions:

• Taihu Lake exhibits some of the highest microplastic contamination levels reported globally for freshwater lakes.
• Microplastic pollution is pervasive in Taihu Lake, affecting not only water bodies but also aquatic organisms.
• The findings highlight the urgent need for effective management strategies to mitigate microplastic pollution in large freshwater systems.