ZeroPM removal workshop: Navigating the PFAS chemistry in complicated samples: Analysis in the Modern Laboratory and Future Prospects

Navigating PFAS Chemistry in complicated samples: Analysis in the Modern Laboratory and Future Aspects By Alexandros G. Asimakopoulos (PhD), Professor •EnviroChemistry Lab •How did it all start? -1938: The chemistry for PFAS (Perand polyfluoroalkyl substances) was initially discovered by Roy J Plunkett at Dupont’s Jackson Laboratory in Deepwater, New Jersey. Solid waxy powder Tetrafluoroethylene (TFE) -1945: DuPont commercialized PTFE as Teflon -PTFE was resistant to corrosion, had low surface friction, and high heat resistance. -TFE can cyclize with a wide variety of compounds which led to the creation of a range of organofluorine compounds. -1950s: First large-scale release of waste by 3M is documented in Lake Elmo, Minnesota, USA -1954: DuPont, received an inquiry about C8 (PFOA) "possible toxicity." -1961: PFOA low dose exposure was linked to the enlargement of rats’ testes, adrenal glands, and kidneys. So the first attempts for measuring fluorinated organic compounds/classes can be documented back to the late 1940s. •How many PFAS do we have ? https://doi.org/10.1016/j.jfluchem.202 5.110444; •PFAS Determination https://doi.org/10.1016/j.trac.2020.116114 0165-9936 edited, •Discovered that samples of his own blood serum contained two distinct forms of fluoride. •Only one of these was exchangeable with radioactive fluoride. The other, non-exchangeable form was detectable as fluoride only when sample preparation included ashing. Fluoride -Non-exchangeable form -Exchangeable form The inorganic fluorine was exchangeable with radioactive fluoride. The organic fluorine was detectable as fluoride only when sample preparation included ashing! •Organic Fluorocompounds vs. Inorganic fluorine 1976: •Intensified research on Organic Fluorocompounds •Navigating common sample preparation pitfalls DELAY COLUMN EXPLANATION; https://doi.org/10.1007/s00216-022-03905-y; https://doi.org/10.1016/j.trac.2023.117062 •If instrumental background levels were found, they were eliminated before analyses by injecting sufficient blanks to cleanse the system (8 to 10 blanks were required). •Additionally, to minimize build-up of PFCs during mobile phase equilibration and to keep background levels constant, the time duration for which the system was kept under initial conditions was maintained as short as possible. •Prior to daily use, we flushed the LC column with elution solvents [MeOH/5 mM ammonium formate (70 : 30, % v/v)] before initiating a sequence. •Tackling Background concentrations •TOP assay and Target Analysis https://doi.org/10.1016/j.teac.2024.e00242 •TOP assay and Target Analysis in Biological Media Distribution of PFCAs concentrations before and after TOP assay in shellfish (a, n=30), shorebird serum (b, n=12), shorebird red blood cell (c, n=12), and shorebird liver (d, n=25) •TOP assay and Target Analysis in Biological Media •TOP assay and Target Analysis in Environmental Media •TOP assay and Target Analysis in Environmental Media Under review https://doi.org/10.1016/j.teac.2024.e00242 Under review Thank you all for your attention! https://www.ntnu.edu/chemistry/research/envchem/asimakopoulos-group/