综述：生态系统中的微塑料：生态毒理学威胁及其缓解与治理策略

《Frontiers in Marine Science》：Microplastics in ecosystems: ecotoxicological threats and strategies for mitigation and governance

微塑料（MP）污染已成为全球性环境威胁，影响生态完整性、食品安全及人类健康。本文系统综述了MP的来源（分解大塑料及工业排放）、环境分布（水、土、大气及生物体内）、检测技术（光谱、机器学习、LIBS）及降解策略（生物降解、光催化、磁分离）。研究发现MP通过食物链传递导致生物积累和毒性效应，而AI增强检测、微生物降解及政策框架是关键治理路径。需多学科协作推动从实验室到实地的综合解决方案，以实现微塑料零污染生态系统。

　　
Microplastic (MP) pollution has emerged as a pressing global challenge, affecting ecosystems, human health, and environmental sustainability. This analysis synthesizes the current understanding of MP sources, distribution, impacts, and mitigation strategies, emphasizing the need for interdisciplinary collaboration and innovative solutions.

### 1. **Production and Environmental Entry of Microplastics**
Plastic production has surged, reaching 9 billion tonnes annually by 2020, with Asia as the top contributor. Only 78% of plastic waste is managed properly, leaving 22% to pollute ecosystems. Single-use plastics, particularly in packaging and textiles, are major contributors. These plastics fragment into microplastics (MPs) through UV degradation, mechanical abrasion, and biological processes. Primary MPs (e.g., microbeads, fibers) enter environments directly, while secondary MPs result from larger plastics breaking down. Urban runoff, wastewater discharge, and atmospheric deposition are key pathways for MPs to reach aquatic systems, sediments, and even the air.

### 2. **Distribution and Ecological Impact**
MPs are pervasive in marine, freshwater, and terrestrial ecosystems. Marine environments face significant pollution from rivers, fishing gear, and coastal waste. Freshwater systems, including rivers and lakes, accumulate MPs through urban runoff and industrial discharge. Terrestrial ecosystems are impacted by agricultural plastics, construction waste, and atmospheric deposition. Studies highlight that MPs vary in size (1 μm–5 mm), shape (fibers, fragments, films), and polymer type (PE, PP, PET), influencing their behavior and toxicity.

The ecological impact is severe. In aquatic environments, organisms from plankton to whales ingest MPs, leading to physical blockages, oxidative stress, and bioaccumulation of toxins like heavy metals and persistent organic pollutants (POPs). Terrestrial ecosystems experience altered soil microbiota, reduced agricultural yields, and toxicity to plants and animals. Atmospheric deposition of MPs poses inhalation risks to humans and wildlife.

### 3. **Detection and Analytical Challenges**
Detecting MPs is complex due to their small size, diverse morphologies, and the lack of standardized protocols. Traditional methods like visual identification and density separation are error-prone. Advanced techniques such as hyperspectral imaging, machine learning algorithms, and laser-induced breakdown spectroscopy (LIBS) have improved sensitivity and accuracy. For example, LIBS enables real-time monitoring of MPs in water and tissues, while AI-enhanced imaging automates identification in complex matrices.

### 4. **Toxicological Effects and Health Implications**
MPs carry toxic additives (e.g., BPA, DEHP) and adsorb pollutants like heavy metals and pesticides. In aquatic life, they disrupt reproduction, immunity, and growth, with effects magnified through trophic transfer. Marine species such as mussels, fish, and seabirds exhibit bioaccumulation, leading to chronic health issues. Terrestrial impacts include soil degradation and toxicity to农作物的. Humans face risks through ingestion (drinking water, seafood), inhalation (airborne MPs), and dermal exposure, potentially causing cancer, reproductive disorders, and immune suppression.

### 5. **Mitigation Strategies and Innovations**
Addressing MP pollution requires a multifaceted approach:
- **Prevention**: Reducing plastic production and consumption, especially single-use plastics. Promoting biodegradable alternatives and circular economy models to minimize waste generation.
- **Treatment Technologies**:
- *Physical Methods*: Filtration, sedimentation, and magnetic separation are effective for large-scale MP removal but face limitations in efficiency and scalability.
- *Chemical Methods*: Advanced oxidation processes (AOPs) like photocatalysis and Fenton oxidation break down MPs into harmless byproducts. Coagulation and adsorption techniques enhance removal from wastewater.
- *Biological Solutions*: Engineered microbes (e.g., *Ideonella sakaiensis*) and biofilms degrade MPs enzymatically. Fungi and algae show potential in breaking down plastics under specific conditions.
- **Policy and Governance**: Strengthening regulations on plastic production and waste management, incentivizing recycling, and enforcing bans on single-use plastics. International cooperation is critical to address cross-border pollution and harmonize standards.

### 6. **Emerging Trends and Research Gaps**
Recent advances include AI-driven detection systems and nanomaterial-based separation methods. For example, machine learning algorithms optimize hyperspectral imaging for MP identification, achieving over 94% accuracy. Nanomaterials like graphene oxide and magnetic carbon nanotubes enhance adsorption and removal efficiency. However, challenges persist:
- **Detection Standardization**: Lack of uniform protocols for sampling, extraction, and analysis complicates data comparison.
- **Treatment Scalability**: Many methods are lab-based and lack field validation. High costs and operational complexity hinder large-scale adoption.
- **Ecotoxicological Data**: Limited understanding of long-term effects of MPs on ecosystems and human health, particularly at the nanoscale.

### 7. **Future Directions**
- **Interdisciplinary Research**: Integrating environmental science, materials engineering, and public policy to develop holistic solutions.
- **Advanced Technologies**: Leveraging synthetic biology to engineer microbes with enhanced degradation pathways and AI for real-time monitoring.
- **Circular Economy**: Transitioning from linear "take-make-dispose" models to circular systems where plastics are reused, recycled, or composted.
- **Global Collaboration**: International agreements to reduce plastic waste discharge, standardize detection methods, and share best practices.

### Conclusion
Microplastic pollution is a systemic issue requiring global cooperation across sectors. While progress in detection and treatment technologies offers hope, scaling solutions and ensuring compliance with policies are critical. A shift toward sustainable materials, robust waste management, and public engagement is essential to protect ecosystems and human health. Future research must prioritize interdisciplinary innovation, standardized protocols, and long-term ecological impact assessments to achieve a microplastic-free future.