Mechanistic studies of perfluorooctane sulfonate, perfluorooctanoic acid uptake by maize (Zea mays L. cv. TY2)

Abstract

Background and aims Perfluorinated compounds (PFCs) are of particular environmental concern. The migration of PFCs from soil to plants is a likely pathway for PFCs to enter the human food chain. This study aimed to investigate the uptake mechanisms of perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) by maize (Zea mays L. cv. TY2).Methods Hydroponic greenhouse experiments were performed. Results The kinetics of PFOS and PFOA uptake fitted Mechaelis-Menten equation well, suggesting their carrier-mediated influx processes. Uptake of PFOS was insensitive to metabolic inhibitors (NaN 3 and Na 3 VO 4 ). In contrast, treated with NaN 3 and Na 3 VO 4 reduced the uptake of PFOA by 83 and 43 % respectively. PFOS uptake was decreased by 31 % and 25 % when plants were treated with aquaporin inhibitors, AgNO 3 and glycerol, respectively, while aquaporin inhibitors had no effect on PFOA uptake. Anion channel blockers, 4, 4′-diisothiocyanostibene-2,2′-disolfonate (DID) and 5-nitro 2-(3-phenylpropylamine) benzoic acid (NPPB) inhibited the uptake of PFOS by 33 % and 30 %, respectively. Anion channel blocker anthracene-9-carboxylic acid (9-AC) decreased the uptake of PFOA by 28 %. No competitive uptake was found between PFOS and PFOA. Conclusions Uptake of PFOS and PFOA by maize may have different mechanisms.

Pathways and factors for food safety and food security at PFOS contaminated sites within a problem based learning approach

“…Therefore, irrigation and rainfalls may contribute to PFOS levels in soil, also in areas without inputs from contaminated sludges. Plant/crop uptake of PFOS takes place to some extent (Dreyer et al, 2010;Felizeter et al, 2012;Wen et al, 2013;Zhao et al, 2013). However, as matter of the strong PFOS binding to organic carbon and anion exchange moieties in soil texture the uptake is moderate and may e.g.…”

The roles of protein and lipid in the accumulation and distribution of perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) in plants grown in biosolids-amended soils

“…They tend to accumulate in protein-rich tissues in fish and animals, such as liver and blood, rather than in fat tissues (Hoff et al, 2003). Wen et al (2013) found that the kinetics of PFOS and PFOA uptake by plant fitted Mechaelis-Menten equation well, suggesting their transport protein-mediated influx processes. In contrast, Felizeter et al (2012) suggested that uptake of PFASs by lettuce root was mainly governed by sorption to lipidrich root solids.…”

“…Up until now, PFOS and PFOA have been detected in all environmental and biological matrices, including the atmosphere Ahrens et al, 2011;Dreyer et al, 2009), soil (Kim et al, 2015;Wen et al, 2014;Washington et al, 2010), water (Eschauzier et al, 2010;Bossi et al, 2008), sediment (Kwadijk et al, 2010), biota (Houde et al, 2011), and human serum (Gao et al, 2015). Adverse effects of PFOS and PFOA on plants, animals and humans have been reported (Wen et al, 2013;Stevenson et al, 2006). Due to their global distribution, environmental persistence, long distance transportation, and potential accumulation and toxicity, PFASs have been at the center of an increasing number of environmental monitoring studies.…”

Accumulation and phytotoxicity of perfluorooctanoic acid in the model plant species Arabidopsis thaliana

“…Blaine et al (2014a) measured the concentrations of PFOA in radish and tomato and found that PFOA was highest in the shoots of the crops. Wen et al (2013) showed that the uptake of PFOA by maize root was an energy dependent active process, although the membrane transporters responsible for PFOA uptake remain unknown. Different from many organic (e.g.…”

“…There have been some reports on the effects of PFOA on plants, including agricultural crops (Stahl et al, 2009;Wen et al, 2013) and vegetables (Blaine et al, 2014a;Zhao et al, 2011). Most of the studies have focused on quantification of PFOA in plants and the potentiality of bioaccumulation and biomagnification of PFOA in the human food chain.…”