New Insights into Concrete Contamination by Persistent Fluorochemicals from Firefighting Foams
Seminar
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Date
19 Mar 2025
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Organiser
CEE / HKIE Civil Division
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Time
17:00 - 18:00
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Venue
Online via Webinar
Speaker
Prof. Jinxia LIU
Enquiry
CHAN, Winnie PK [CEE] winnie.pk.chan@polyu.edu.hk
Summary
Contamination by per- and polyfluoroalkyl substances (PFAS) in soil, water, and biota is well-documented, but their presence in concrete exposed to Aqueous Film-Forming Foams (AFFF) at airports and military bases remains underexplored. Recent field studies in Australia have revealed significant PFAS contamination in concrete, influenced by exposure duration and intensity, and demonstrated that PFAS can back-diffuse during rainfall, leaching slowly over decades. Laboratory experiments confirmed PFAS uptake into the porous concrete matrix, with surface-damaged concrete and exposed interfacial transition zones accelerating PFAS migration. Notably, we identified a previously unreported decomposition of PFAS compounds, despite their high chemical stability, in the concrete matrix. Robust sample preparation methods were developed, and DESI-MS proved effective in visualizing PFAS penetration. This study highlights concrete’s dual role as a PFAS reservoir and source, with significant implications for groundwater contamination and environmental management.