GenX uptake by wheat and rice in flooded and non-flooded soils: a greenhouse experiment

Amnah Al Zbedy; Viktoria Müller; Andrew Kindness; Rainer Ebel; Gareth J Norton; Joerg Feldmann

doi:10.1007/s11356-023-31160-w

GenX uptake by wheat and rice in flooded and non-flooded soils: a greenhouse experiment

Environ Sci Pollut Res Int. 2024 Jan;31(1):1607-1620. doi: 10.1007/s11356-023-31160-w. Epub 2023 Dec 4.

Authors

Amnah Al Zbedy^{1

2

3}, Viktoria Müller^{4

5}, Andrew Kindness^{5

6}, Rainer Ebel², Gareth J Norton¹, Joerg Feldmann⁷

Affiliations

¹ School of Biological science, University of Aberdeen, Machar Drive, Aberdeen, AB24 3FX, UK.
² School of Natural and Computing Sciences, University of Aberdeen, Meston Walk, Aberdeen, AB24 3UE, UK.
³ Department of Chemistry, Al-Qunfudhah University College, Umm Al-Qura University, Makkah, Saudi Arabia.
⁴ TESLA-Analytical Chemistry, University of Graz, Universitätsplatz 1, 8010, Graz, Austria.
⁵ The James Hutton Institute, Craigiebuckler, Aberdeen, AB15 8QH, UK.
⁶ School of Chemistry and Physics, University of KwaZulu-Natal, Private Bag X54001, Durban, 4000, South Africa.
⁷ TESLA-Analytical Chemistry, University of Graz, Universitätsplatz 1, 8010, Graz, Austria. Joerg.feldmann@uni-graz.at.

Abstract

GenX (hexafluoropropylene oxide dimer acid) belongs to the group of per- and poly-fluoroalkyl substance (PFAS) compounds introduced to replace perfluorooctanoic acid (PFOA), which has been phased out in industrial and consumer product formulations. While GenX has been investigated in lab animals, there is limited information available regarding its uptake and translocation in wheat and rice. This study reports on a greenhouse experiment in which wheat and rice grown under flooded and non-flooded conditions were exposed to two GenX concentrations in the soil (0.4 mg kg^-1 and 2 mg kg^-1). GenX was analysed in the soil, porewater and shoots using targeted liquid chromatography-tandem mass spectroscopy (LC-MS/MS) analysis. Extractable organic fluorine (EOF) was determined using high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-GFMAS) instrument. Results showed that different species took up different amounts of GenX. The GenX concentration in rice shoots was found to be 2.34 (± 0.45) and 4.11 (± 0.87) μg g^-1 under flooded and non-flooded conditions, respectively, at a low exposure level. At high exposure, the GenX concentrations in flooded and non-flooded rice shoots increased threefold to 10.4 (± 0.41) and 13.4 (± 0.72) μg g^-1, respectively. Wheat shoots showed similar concentrations and increases between low- and high-level exposure. The translocation factor was significantly higher (P = 0.013) in non-flooded rice compared to flooded rice. The GenX bioaccumulation behaviours under the same culture conditions (e.g. temperature, humidity, light, same GenX concentration in the soil) were significantly different in non-flooded and flooded rice (P < 0.001). Non-flooded rice plants displayed a higher level of GenX bioaccumulation than flooded ones. Following exposure to GenX, flooded rice plants showed a reduction in biomass (25%) compared to the control plants (P < 0.014). Our findings indicate that GenX is a bioaccumulative compound, the presence of which likely inhibits the growth of plants.

Keywords: Agriculture practise; EOF; PFAS; Plant uptake; Rice; Wheat.

MeSH terms

Animals
Chromatography, Liquid
Oryza*
Soil
Soil Pollutants* / analysis
Tandem Mass Spectrometry
Triticum

Substances

Soil
Soil Pollutants