Perfluorinated alkylated substances in the aquatic environment: an Austrian case study

Area of Science:

• Environmental Chemistry
• Environmental Science
• Analytical Chemistry

Background:

• Perfluorinated alkylated substances (PFAS) are globally significant due to their environmental persistence.
• Eleven PFAS, including perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), were analyzed.
• PFAS are categorized into perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates (PFS), and perfluoroalkyl sulfonamides (PFSA).

Purpose of the Study:

• To analyze PFAS concentrations in surface waters and sediments.
• To determine the contribution of wastewater discharges to PFAS mass flow in rivers.
• To identify potential sources of PFAS contamination in aquatic environments.

Main Methods:

• Analysis of eleven PFAS compounds in surface water and sediment samples.
• Quantification of perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS) in surface waters.
• Determination of PFCAs, PFS, and PFSA in lake and river sediments.
• Calculation of proportional mass flows from wastewater discharges.

Main Results:

• Maximum concentrations of 21 ng/l for PFOA and 37 ng/l for PFOS were found in surface waters.
• PFCAs were detected in most lake sediments (up to 1.7 microg/kg dry wt), while PFSA and PFS were not.
• PFOA, PFHxA, and PFHpA were present in all Danube river sediments (0.1-5.1 microg/kg dry wt).
• Wastewater discharges accounted for over 50% of PFAS mass flow in rivers, despite being only up to 10% of the average flow.

Conclusions:

• Wastewater discharges are a major contributor to PFAS mass flow in rivers.
• PFAS contamination in surface waters originates from multiple sources, including wastewater, point sources, precursor degradation, and runoff.
• Further investigation into diverse PFAS sources is crucial for effective environmental management.