Bioavailability of cerium oxide nanoparticles to Raphanus sativus L. in two soils

Soil organic matter influences cerium translocation and physiological processes in kidney bean plants exposed to cerium oxide nanoparticles

“…OMES-OM fraction accumulated 4.9 ± 2.9 to 118 ± 10 mg/kg Ce at 62.5 to 500 mg/kg nanoCeO 2 exposure treatments. In a recent study by Zhang et al (2016), higher concentration of oxidizable fraction of CeO 2 was found in soil with higher organic matter, suggesting strong association of nanoCeO 2 in soil with SOM. As Miracle Gro potting mixes are commercially sold as mix of nutrient supplements for plants, untreated OMES (10.1% SOM) also had significantly higher levels of macronutrients like N and S, and micronutrients like Fe, than LOMS (4.2% SOM) ( Table 1).…”

“…Values are expressed as mean ± SE (n = 4). Bars with different letters within same soil type, represent significant difference at p ≤ 0.05. holds higher concentration of Ce in soils with lower SOM (Zhang et al, 2016), which decreases with increase in exposure concentration. In our study, significant leaching was not observed in either soil, since the irrigation water was adjusted to the soil pore volume.…”

“…In LOMS, the surface charge of the heterogeneous soil colloids allows the nanoparticles to aggregate and thereby restrict their ability to pass through the soil pores (Schwabe et al, 2013). As shown by Zhang et al (2016), the major proportion of the Ce from nano-CeO 2 in soil gets associated with the silicate minerals in the residual fraction. Moreover, at 100 mg/kg nano-CeO 2 , the residual fraction Fig.…”

“…In corn plants, lower Ce translocation to aerial tissues was observed in organic matter rich soil, compared to natural unenriched soil amended with bare as well as alginate-coated nano-CeO 2 (Zhao et al, 2012b). According to Zhang et al (2016), silty loam soil with lower SOM content (~2%) had more exchangeable/bioavailable fraction of Ce, leading to higher translocation to radish shoots, compared to loamy sand soil (~12%). This suggests that soil components have a high potential to modulate the surface properties of ENMs.…”

Interactions between nanoparticles and plants: phytotoxicity and defense mechanisms

“…When the biomass of radishes was compared in silty loam (∼2.21% ± 0.04% soil organic matter) and loamy sand (∼11.87% ± 0.56% soil organic matter), the former had significantly higher root biomass and the presence of 1000 mg/ kg CeO 2 NPs made no substantial difference. The Ce accumulation in fine roots and in the storage root showed that growth in loamy sand was higher than that in silty loam (Zhang, Musante, et al 2015). Kidney bean plants exposed to CeO 2 NPs for 52 days in a low organic matter soil usually possessed higher Ce concentration than the same tissues collected from an organic matter-enriched soil (Majumdar et al 2016).…”