Exploring correlations between microplastics, microorganisms, and water quality in an urban drinking water source

Area of Science:

• Environmental Science
• Ecotoxicology
• Microplastic Research

Background:

• Microplastic pollution is a growing concern in freshwater systems, impacting river ecology and ecosystem health.
• Understanding the distribution and effects of microplastics is crucial for risk assessment and mitigation strategies.
• The Xiangjiang River, an urban drinking water source, faces potential microplastic contamination.

Purpose of the Study:

• To investigate the correlations between microplastics and free-living microorganisms in the Xiangjiang River.
• To analyze the influence of microplastic properties (size, shape, color) on water indicators and microbial communities.
• To apply multivariate statistical analysis to understand complex interactions within the river ecosystem.

Main Methods:

• Sampling of surface water and sediments from the Xiangjiang River.
• Quantification and characterization of microplastics (size 50 μm to 5 mm).
• Multivariate statistical analysis to assess correlations between microplastics, water quality indicators, and microbial communities (Proteobacteria, Chloroplastida).

Main Results:

• Microplastic abundance ranged from 7.32 ± 2.36 items L⁻¹ in surface water to 150 ± 75.6 items kg⁻¹ dw in sediments, indicating pollution.
• Higher microplastic concentrations were found in urban areas and downstream of wastewater treatment plants.
• Microplastic properties (transparent/black color, 50-100 μm size) showed stronger correlations with water indicators and microorganisms than overall abundance.

Conclusions:

• Microplastic pollution exists in the Xiangjiang River, even in protected drinking water sources.
• Microplastic properties, not just abundance, are key factors influencing their ecological impact and interactions.
• Multivariate statistical analysis reveals complex relationships between microplastic characteristics, water quality, and microbial life in river systems.