Microplastic toxicity: mechanisms, assessment methods, and future research directions.

Area of Science:

• Environmental Science
• Toxicology
• Ecotoxicology

Background:

• Microplastics (MPs) are pervasive environmental contaminants with adverse effects on organisms and human health.
• Existing reviews often focus on isolated aspects of MP toxicity or assessment methods, leaving critical knowledge gaps.
• A unified understanding of MP impacts across different domains is needed.

Purpose of the Study:

• To synthesize MP toxicity mechanisms into a unified "particle-environment-organism" cascade.
• To critically evaluate methodological advances and propose a standardized dosing framework for improved cross-study comparison.
• To bridge ecological and human toxicology with an integrative model and outline research/regulatory strategies.

Main Methods:

• Literature synthesis of physical, chemical, and biological MP toxicity mechanisms.
• Critical evaluation of existing methodologies for MP assessment.
• Development of an integrative conceptual model for MP risk assessment.

Main Results:

• A unified "particle-environment-organism" cascade model for MP toxicity.
• A proposed standardized dosing framework to enhance comparability of MP studies.
• An integrative model linking MP properties to ecological and human health outcomes.

Conclusions:

• This review synthesizes current understanding of MP toxicity and provides a framework for enhanced study comparability.
• The proposed framework guides future research and regulation, aiming to translate lab findings into practical risk mitigation strategies.
• Bridging ecological and human toxicology is crucial for addressing the real-world impact of microplastic pollution.