Bioavailability and toxicity of legacy and emerging per- and polyfluoralkylated substances (PFAS) in a terrestrial food chain: effects at different levels of biological organisation (BIOTOX-Terra)

Per- and polyfluoroalkyl substances (PFAS) are chemicals globally present in the environment and biota, as a result of their massive production and use in numerous applications, such as food contact paper, fire-fighting foams, textiles, construction and cleaning products. Their bioaccumulative and persistent properties have led to global regulatory measures for PFOS and PFOA. These are the most frequently detected legacy PFAS and their concentrations are still very high in the environment and biota. In addition, there are many emerging PFAS alternatives developed, with similar structures and chemical properties, not yet regulated and hence used unrestrictedly. However, very little or no information is available on the bioavailability, biomagnification and toxic effects of these emerging compounds, particularly for the terrestrial environment. PFAS may thus accumulate in the environment, posing risks to organisms. There are also many uncertainties on which factors might influence the bioavailability and biomagnification, especially of emerging PFAS. The identification of emerging PFAS, which have largely replaced the legacy PFAS, would allow us to investigate the environmental relevance of currently-used PFAS, as well as to characterize possible point sources. Detailed field studies on soil, plants, invertebrates (e.g. earthworms, woodlice, caterpillars, snails, slugs, and spiders), and great tits (Parus major; a songbird model species) planned in this project will provide us with: 1) an overview of the distribution of legacy and emerging PFAS present in the terrestrial environment near a fluorochemical polluting hotspot in Antwerp, 2) how the concentrations in the food chain are influenced by soil properties, and 3) their potential toxicity in key model species. In addition, experimental lab studies with PFAS and elevated temperature (T) as stressors on terrestrial invertebrates and plants will be performed to: 4) disentangle causal links from confounding effects regarding the soil properties, 5) verify whether or not increased T and PFAS have an additive toxic effect when combined, and 6) create a mechanistic framework explaining the underlying subcellular basis of root growth responses towards PFAS/increased T in the plant model species Arabidopsis thaliana. This project will allow us to understand the bioavailability and mechanism of the toxicity of emerging and legacy PFAS in plants, invertebrates, and birds and will offer instruments for regulators to assess the environmental risk and potential effects on human health.

Keywords:ECOTOXICOLOGY, BIOCHEMISTRY, MONITORING, IMMUNOLOGY

Disciplines:Animal immunology, Plant biochemistry, Environmental chemistry, Environmental impact and risk assessment, Environmental monitoring