Soybean susceptibility to manufactured nanomaterials with evidence for food quality and soil fertility interruption

Abstract

Based on previously published hydroponic plant, planktonic bacterial, and soil microbial community research, manufactured nanomaterial (MNM) environmental buildup could profoundly alter soil-based food crop quality and yield. However, thus far, no single study has at once examined the full implications, as no studies have involved growing plants to full maturity in MNM-contaminated field soil. We have done so for soybean, a major global commodity crop, using farm soil amended with two high-production metal oxide MNMs (nano-CeO 2 and -ZnO). The results provide a clear, but unfortunate, view of what could arise over the long term: (i) for nano-ZnO, component metal was taken up and distributed throughout edible plant tissues; (ii) for nano-CeO 2 , plant growth and yield diminished, but also (iii) nitrogen fixation-a major ecosystem service of leguminous crops-was shut down at high nano-CeO 2 concentration. Juxtaposed against widespread land application of wastewater treatment biosolids to food crops, these findings forewarn of agriculturally associated human and environmental risks from the accelerating use of MNMs.nanoparticles | nanotechnology | agriculture

Environmental release, fate and ecotoxicological effects of manufactured ceria nanomaterials

“…However, the inhibition of bacterial nitrogen fixation did not necessarily result in nitrogen shortage for the plants; soybeans exposed to high doses of nanoceria actually grew better those exposed to low doses of nanoceria in the Priester study, 83 suggesting that the plants successfully used an alternative source of nitrogen for growth. In a related study, Bandyopadhyaya et al 84 observed that nanoceria at 31-125 mg/l significantly inhibited the growth of Sinorhizobium meliloti, the primary symbiotic nitrogen fixing bacteria of alfalfa.…”

“…The authors also observed nanoceria in the vasculature of leaf veins, providing further evidence that nanoceria may be transported from roots to shoots with water through vascular tissues. 82 Priester et al 83 noted that soybean exposed to 100-1000 mg/kg nanoceria had root ceria content of up to 200 mg/kg but that translocation was minimal. Plant growth and yield were modestly reduced but importantly, nitrogen fixation was almost entirely eliminated.…”

Interactions between engineered nanomaterials and agricultural crops: implications for food safety

“…In Glycine max (soybean), nitrogen fixation potential per nodule was also severely diminished at medium and high nano CeO 2 treatments (50, 100 g/kg soil), which are correlated to absent bacteroids in nodules (Priester et al, 2012). Similarly, nano TiO 2 disrupted Rhizobium-legume symbiosis between Pisum sativum (peas) and R. leguminosarum bv.…”

“…To date, the knowledge of ENMs-crop interactions in soil-based systems is very limited. In some published trials, sand or soil was either amended with nanomaterial powders or with ENMs suspensions (Du et al, 2011;Dimkpa et al, 2012;El-Temsah and Joner, 2012;Priester et al, 2012;Zhao et al, 2012a;Khodakovskaya et al, 2013). A design with outdoor lysimeters under field condition was first introduced to investigate the impact of ENMs on Triticum aestivum (wheat) growth and soil enzyme activities; here, the topsoil was ex-situ amended with TiO 2 and ZnO nanoparticles (Du et al, 2011).…”

Advanced Analytical Techniques for the Measurement of Nanomaterials in Food and Agricultural Samples: A Review

“…However, this could release an excess of ENMs in soil, ground water, and food products, with unknown consequences (Klaine et al, 2008;Boxall and Molhave, 2011). ENPs like ZnO and CeO 2 ENPs, widely used in food and commercial products, are potentially toxic to humans and plants (Nel et al, 2006;Lin et al, 2009;Moos et al, 2011;Lee et al, 2012;Mihranyan et al, 2012;Priester et al, 2012). These, as well as silver (Ag), gold (Au), and iron oxide (Fe 3 O 4 ) ENPs, are potentially toxic to soil microbiota (Barrena et al, 2009;Ge et al, 2011;Sinha et al, 2011;Bandyopadhyay et al, 2012a).…”