Initiating environmental microplastics analysis: A review and planning guide with practical insights from laboratory implementation

Recent research indicating that microplastics (MPs) are ubiquitous and may have harmful environmental and human health effects has led to widespread interest in MP monitoring. While a plethora of MP methods are available and in development, challenges remain, and little comprehensive advice is available to inform interested laboratories about planning, initial setup, time investment, capital and operating costs, and logistics. Grounded in current literature and informed by the authors' experience initiating environmental MP analysis, this review provides comprehensive, practical guidance that can assist other laboratories in planning and decision-making for initiating MP analysis. This work focuses on commonly used nondestructive methods, including physical isolation, quantification, and characterization, though alternative methods are also presented. Quality Assurance and Quality Control (QA/QC), including contamination reduction, is addressed as the primary challenge to robust analysis. An iterative planning diagram that works backwards from characterization method to sampling plan is provided. Time, costs, and logistics are also discussed. This review provides valuable information to utility, commercial, and research laboratories as they plan to undertake MP analysis. Although not intended to be the best fit for every laboratory, the authors' methods are referred to throughout to serve as a concrete example, and the developed standard operating procedures (SOPs) are also provided in Supplementary Material.