(331c) Methodology Development for the Identification of Environmental Microplastic Samples Using Py-GC/MS

Microplastic pollution has gained traction over the past few years for its increasing threat to the environment and while several researchers have conducted studies to understand the impact, there remains significant research gaps in the characterization and identification of the plastic waste. Apart from being complex in size, shape, color, etc., environmental microplastics undergo weathering which can significantly affect the original properties of the material. Additionally, field samples are likely a mixture of organics and inorganics that are difficult to separate. These drawbacks make traditional characterization methods, such as microscopy or spectrometry, challenging. In their place, this research proposes a pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) method that can accurately be used to identify environmental microplastics by their characteristic pyrolyzates and additives. Microplastics used in this study were sampled from the Concord River and treated with either a sodium hypochlorite mixture (household bleach) or potassium hydroxide (KOH) to understand the significance of digesting environmental samples and its effect on analysis results. The data obtained from this study suggests high concentrations of rubbers, styrenes, and acrylics in local waterways though in different proportions depending on the pretreatment method. This work provides foundational knowledge on the prevalence of microplastics in the environment and is intended to be a foundation for future microplastic studies.