Assessing Mass-based Fates of Microplastics Throughout the Waste Water Treatment Process Using a Novel TD-GC-MS MethodologyAnalyzing Microplastics in the Environment
Oral Presentation
Presented by C. Widdowson
Prepared by H. Calder1, L. An2, Y. Zhang3, Z. Wu4
1 - Markes International, 1000B Central Park, Western Avenue, Bridgend, (State/Province), CF31 3RT, United Kingdom
2 - State Key Laboratory of Environmental Criteria and Risk Assessment,, Chinese Research Academy of Environmental Sciences, Beijing, Beijing, 100012, China
3 - Key Laboratory of Water and Air Pollution Control of Guangdong Province, South China Institute of Environmental Sciences, MEE, Guangzhou, Guangzhou, 510655, China
4 - State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, Beijing, 100012, China
Contact Information: [email protected]; 01443230935
ABSTRACT
Sewage treatment plants (STPs) play a vital role in removing microplastics from wastewater but are also significant sources of microplastic pollution in the environment. Since STPs are not specifically designed for microplastic removal, understanding the mass-based fate of these particles during treatment is crucial for improving removal efficiency.
In this study, a thermal desorption–gas chromatography–mass spectrometry (TD–GC/MS) method was developed to quantify five common microplastics—polyethylene (PE), polypropylene (PP), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene glycol terephthalate (PET)—within the size range of 0.22 μm to 5.00 mm. This approach was applied to assess microplastic fate throughout the entire STP treatment process. Unlike pyrolysis (Py)-GC/MS analysis the thermal desorption approach utilises an offline pyrolysis step which enables a large sample size; resulting in high levels of reproducibility between samples. The offline pyrolysis step also means that the pyrolyzate is not transferred to the GC column increasing robustness and time needed between system maintenance.
In this presentation we will detail how the mass-based quantitation used was a considerable improvement on estimations based on particle volume. The polymer concentrations for four size ranges was analysed at five stages during the waste water treatment process (influent prior to treatment, primary sedimentation tank, aerated grit chamber, secondary sedimentation tank and final effluent).The results compare the polymer abundance for the five polymer types and whether particle size impacts the efficiency of removal.
