Microplastics in Waste Water Treatment Plants 2022

This report details a study to ascertain levels and compositions of microplastics in selected wastewater treatment plants (i.e., Publicly Owned Works or POTWs) in coastal California, and removal efficiencies for microplastics at various levels of wastewater treatment (e.g., primary, secondary, tertiary). Seven POTWs in major coastal urban areas of the state participated in this study. Wastewater samples were collected in influent, primary effluent, secondary effluent, tertiary effluent, and biosolids at various locations at these POTWs between November 2022 and December 2023. For each of two sampling events per POTW, up to 5800 L of effluent water was collected using online filtration, and up to 40 L of influent water was collected using standard integrative autosamplers. Microplastic particles were extracted from these samples using an acid/alkaline digestion technique to destroy interferences from organic particulate matter and density separation to remove inorganic particulates, and quantified and identified using visual microscopy and Fourier-transform infrared (FTIR) spectroscopy. The dataset contains one row for each particle identified in each size fraction of an individual sample, and the associated concentration of the particles, polymer types, morphologies, and colors of particles in that sample. The concentration value is based on the total volume samples and the percentage of the sample processed. (LINK TO ACCOMPANYING REPORT TBD) Not-Applicable