Linking Vegetable Per- and Polyfluoroalkyl Substance Accumulation with Root Chemical Traits

Area of Science:

• Environmental Chemistry
• Plant Science
• Toxicology

Background:

• Per- and polyfluoroalkyl substances (PFAS) are persistent organic pollutants found in food crops.
• Understanding PFAS accumulation in diverse plant species and influencing factors is crucial for food safety.
• Farmland irrigation with treated wastewater presents a potential route for PFAS uptake by vegetables.

Purpose of the Study:

• To investigate PFAS bioaccumulation patterns in 20 vegetable species.
• To correlate PFAS accumulation with root chemical traits in vegetables grown in wastewater-irrigated soil.
• To assess the impact of vegetable type and PFAS species on potential human exposure.

Main Methods:

• Analyzed PFAS concentrations in 20 vegetable species grown in farmland irrigated with treated wastewater.
• Quantified PFAS species, focusing on short-chain perfluorobutanoic acid (PFBA) and long-chain PFAS.
• Examined the relationship between root chemical composition (alkyl carbon, O-alkyl carbon, dissolved organic carbon) and PFAS accumulation.

Main Results:

• Leafy vegetables accumulated significantly higher PFAS concentrations (mean: 9.24 ng/g) than root vegetables.
• Short-chain PFBA was the dominant PFAS species, accumulating in edible aerial parts of leafy vegetables.
• Long-chain PFAS were primarily retained in the roots, with accumulation influenced by root dissolved organic carbon.

Conclusions:

• Plant species and root chemistry significantly influence PFAS bioaccumulation and distribution.
• Crop selection (choosing low-accumulation varieties) can reduce dietary PFAS exposure by up to 90%.
• Rhizosphere management strategies can be employed to mitigate PFAS uptake in food crops.