Microplastic Contamination: Sources, Risks, and Advanced Removal Strategies in Water Treatment

Microplastics (MPs), defined as plastic particles smaller than 5 mm, have infiltrated nearly every environmental compartment, becoming a paramount concern for water security and public health.

Sources and Environmental Burden

The primary sources of MPs are broadly categorized into primary and secondary . Primary microplastics are manufactured at a microscopic size (e.g., microbeads in cosmetics). Secondary microplastics, however, constitute the bulk of contamination, originating from the fragmentation of larger plastic debris due to UV radiation, mechanical abrasion, and weathering. Major contributors include the degradation of synthetic textiles during laundry, tire wear particles, and the breakdown of plastic packaging and agricultural films. Once in aquatic systems, these particles pose ingestion risks to aquatic life and act as vectors for transporting adsorbed pollutants.

Health Risks Associated with Aquatic Microplastics

The presence of MPs in water sources poses significant, though still heavily researched, risks to human health:

• Gastrointestinal Issues: Ingestion can lead to physical irritation and obstruction within the digestive tracts of organisms, including humans.
• Carcinogenic Potential: Microplastics often adsorb toxic chemicals (like PCBs and heavy metals) from the surrounding water. Ingesting these contaminated particles raises concerns about long-term carcinogenic effects.
• Endocrine Disruption: Leaching of chemical additives used in plastic manufacturing (such as phthalates and BPA) can lead to endocrine-disrupting effects, which are particularly concerning for vulnerable populations, especially children, potentially impacting development and hormonal balance.

Removal Strategies in Water Treatment Plants

Effective mitigation relies on incorporating targeted technologies capable of capturing these minute particles:

• Activated Carbon Filters (ACF): While highly effective for removing organic contaminants and improving aesthetic water quality, ACF struggles to completely capture the smallest microplastics due to its reliance on adsorption and pore size limitations, making it insufficient as a standalone solution for MPs.
• Ultrafiltration (UF) and Reverse Osmosis (RO): These membrane-based processes are highly effective. UF membranes, with pore sizes typically ranging from 0.01 to 0.1 μ\muμm, can physically block the vast majority of MPs. RO membranes, operating at the tightest separation level, virtually eliminate microplastics, ensuring high-purity effluent suitable for drinking water standards.
• Electrodeionization (EDI): EDI is primarily used for demineralization. While it functions by separating ions, its tight matrix structure can also contribute to the physical removal of suspended particles, complementing the main filtration steps.

The synergistic application of these technologies, prioritizing advanced membrane filtration, is crucial for
safeguarding water resources against the pervasive threat of microplastic pollution
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