Analytical approaches for quantifying and characterizing microplastics: Environmental impacts and bioaccumulation in aquatic Systems

Background: Microplastics (MPs) are pervasive pollutants found in various environments, including soil, air, and water. Their increasing presence worldwide has raised concerns due to their potential environmental and health impacts. Effective mitigation strategies depend on accurate quantification and characterization of MPs. This review provides an extensive overview of the current methods used for MP detection and analysis, addressing their prevalence and risks, especially in aquatic ecosystems, where MPs are subject to bioaccumulation. Scope: This review focuses on several detection and characterization techniques for MPs, such as Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy (RS), Thermogravimetric Analysis (TGA), microscopy, Nuclear Magnetic Resonance (NMR), and mass spectrometry (MS). It also highlights the pathways through which MPs enter aquatic organisms and their subsequent bioaccumulation, alongside the broader environmental and health implications. Moreover, it explores the challenges in quantifying MPs in different matrices, including biological samples, soil, water, and air, identifying the knowledge gaps that require further investigation. It explores the advantages and limitations of traditional techniques like FTIR, RS, and MS while emphasizing the transformative potential of green chemistry workflows, including solvent-free methods and on-site instrumentation, for sustainable MPs analysis. Key Findings: The review highlights that analytical methods for MP quantification, such as FTIR, RS, and MS, have unique strengths and limitations. FTIR effectively identifies polymers but struggles with MPs smaller than 20 mu m, while RS offers high spatial resolution but is affected by fluorescence interference. Advanced techniques like Pyrolysis-GC/MS provide detailed chemical insights but are resource-intensive. Green chemistry-based workflows, including solvent-free methods and on-site instrumentation, enable sustainable and efficient MP analysis, with sensor-based detection advancing real-time, eco-friendly monitoring. The study emphasizes MPs' ecotoxicological effects, such as endocrine disruption and oxidative stress, along with biomarker responses in aquatic organisms, posing risks to ecosystems and human health. Mitigation strategies focus on standardized protocols, biodegradable alternatives, robust waste management, and high-throughput analytical advancements for improved risk management.