Review of Recent Advances in Microplastic Ecological Risk Assessment: From Problem Formulation to Risk Characterization

Abstract

Microplastic (MP) pollution represents a significant environmental threat, impacting aquatic ecosystems and human health. This review examines critical elements of MP risk assessment, including exposure pathways, properties (polymer type, size, and shape), bioaccumulation, and ecological and health effects. It underscores the challenges of quantifying MP exposure and identifying pollutants, as well as gaps in understanding pollutant adsorption/desorption and biofilm impacts. MPs serve as carriers for organic pollutants, heavy metals, and chemical additives, potentially magnifying toxic effects. Emerging contaminants, such as pharmaceuticals, exacerbate these risks. Laboratory research is crucial to trace MPs through food chains from primary producers to humans and assess bioaccumulation and health impacts. Current assessments, however, are insufficient to provide comprehensive ecological risk evaluations. The review highlights the need for improved methodologies to assess MPs’ fate, trophic transfer, and long-term ecological effects. MPs often release harmful additives like plasticizers and flame retardants, necessitating studies to differentiate the impacts of polymers and additives. It emphasizes integrating MP toxicity data into risk models while fostering collaboration among scientists, policymakers, and communities. The paper advocates for a comprehensive framework combining advanced analytical methods and environmental monitoring to refine risk assessment models. These efforts aim to strengthen public awareness, support informed environmental policies, and promote sustainable practices to mitigate MP pollution impacts. Addressing these research gaps will significantly enhance the scientific understanding of MP risks and guide effective management strategies for environmental and human health protection.