Young Chemist Award

Congratulations to our 14th Annual Young Chemist Award winner, Sarah Ortbal!

The University of Alabama

Research Title: PFAS Evaluation in Various Matrices using Targeted Analysis and Adsorbable Organic Fluorine

Summary: Per- and polyfluoroalkyl substances (PFAS) are persistent, synthetic, organic contaminants frequently used in a variety of consumer and industrial products. Their widespread use has led to the contamination of many waterways. Due to their toxicity at low concentrations, some PFAS are now being regulated in drinking water as low as 4 parts per trillion. This research focuses on improving water quality through comprehensive monitoring, analysis, and treatment of PFAS.

Investigating PFAS behavior throughout wastewater treatment systems is essential to determine where PFAS accumulate or persist, which helps identify areas of concern and informs decisions about where treatment should be implemented in full-scale systems. Streamlined analytical methods for PFAS and the utilization of adsorbable organic fluorine (AOF), a non-targeted analysis for synthetic fluorinated organic chemicals, revealed the overall organic fluorine load throughout wastewater treatment and the potential presence of thousands of PFAS that cannot be detected using traditional targeted methods. Results also identified contaminated chemical additives, revealed PFAS recirculation within biological basins and activated sludge, and demonstrated that non-target analysis can quantify 25 times more fluorinated organics than traditional PFAS methods.

Furthermore, to evaluate the extent of PFAS contamination in surface waters, statewide monitoring was conducted across Alabama. Samples were collected upstream and downstream of wastewater treatment plants in every Alabama county. This work included developing a statewide map of PFAS contamination, highlighting priority watersheds where elevated concentrations warrant further investigation. In this project, analytical capabilities were expanded to include trifluoroacetic acid (TFA), an ultra-short-chain PFAS frequently detected at concentrations orders of magnitude higher than many legacy PFAS. Ongoing work extends this analysis to include diverse water matrices (groundwater, lagoons, direct effluent monitoring, etc.) in coastal counties throughout Alabama and Mississippi.

While PFAS monitoring is crucial for identifying contaminated waters, optimized treatment technologies are also essential for effective PFAS removal and destruction from contaminated waters. One removal technology, ball-milled colloidal activated carbon, enhances PFAS adsorption through decreased particle size, increased surface area, and improved suspension stability. For PFAS destruction, advanced oxidation processes, such as heat-activated peroxydisulfate (PDS), can degrade PFAS into non-toxic byproducts. AOF, fluoride, and targeted PFAS were evaluated in bench-scale experiments, and results indicated significant PFAS defluorination and overall treatment effectiveness of heat-activated PDS.