Jaewoo Choi

“The effect of PFAs alternatives, focusing on PFECA (Perfluoroether Carboxylic Acids) and 6:2 FTS Fluorotelomer Sulfonate), on marine organisms, and their potential structural causes”

Started Dec. 3, 2024

Abstract or project description

Per- and polyfluoroalkyl substances (PFAS) are widely used for industrial purposes due to their incredible properties of resistance to heat, water, and oil. Although these properties are beneficial for consumer home products, textiles, fire retardant, and more, PFAS have raised concerns and found to have serious environmental harms. In response, PFAS alternatives, including Perfluoroether Carboxylic Acids (PFECAs) and 6:2 Fluorotelomer Sulfonate (6:2 FTS), were developed as an attempt to minimize these harms. However, recent studies suggest that although they are marketed as a better choice, these alternatives may also cause environmental and health issues.

This literature review focuses on the structural properties, bioaccumulations and toxicity, and, ultimately, the connection of structure-toxicity of PFECAs and 6:2 FTS regarding various marine organisms. Understanding these effects on marine organisms are important, as marine ecosystems are crucial for global biodiversity. Although both PFECAs and 6:2 FTS is known as an alternative of PFAS, their overall structure is different in that PFECA contains ether-linked perether-linked perfluorinated carbon chains that increase their environmental persistence and mobility, while 6:2 FTS features a fluorotelomer-based sulfonate group, which contributes to its surfactant properties and partial degradation into persistent byproducts.

Both 6:2 FTS and PFECAs demonstrate similar bio accumulation tendencies in marine organisms but differ in toxicity level throughout the food chain and environmental persistence from different structural properties. 6:2 FTS has been found to impact aquatic species in their respiration and reproduction, with a toxicity relatively lower than PFOS. While it is shown that it has no immediate effect, it raises concerns due to potential cumulative effects. PFECAs, which get splitted into long and short chains, illustrate a varying concentration level throughout the food chain. Long chain PFECA show significant biomagnification at higher trophic levels, while short chains accumulate mainly in invertebrates.

Future research should continue to study how specific structural factors of these PFAS alternatives, such as functional groups and molecular length, result in bioaccumulation and toxicity in marine organisms, to inform the development of safer PFAS alternatives that can protect marine biodiversity.