Researchers Examine Soybean Uptake of Nanoparticles from Soil

A recent study has purportedly found that soybean plants can uptake
widely used industrial nanoparticles (NPs) from the soil, raising concerns
about potential effects on the food chain and the next generation of crops.
Jose Hernandez-Viezcas, et al., “In Situ Synchrotron X-ray Fluorescence
Mapping and Speciation of CeO2 and ZnO Nanoparticles in Soil Cultivated
Soybean (Glycine max),” ACS Nano, February 2013. Researchers apparently
used microscopic synchrotron X-ray beams on soybean plants grown in
soil contaminated with zinc oxide (ZnO) and cerium dioxide (CeO2) NPs to
trace “the potential storage of these NPs or their biotransformed products in
edible/reproductive organs of crop plants.”

Although x-ray absorption spectroscopy studies evidently did not find intact ZnO NPs within the plant tissues, micro-X-ray absorption near end structure (µ-XANES) data did identify “O-bound Zn, in a form resembling Zn-citrate, which could be an important Zn complex in soybean grains.” The µ-XANES data also reportedly showed “that Ce remained mostly as CeO2 within the plant.”

“To our knowledge, this is the first report on the presence of cerium dioxide
and zinc compounds in the reproductive/edible portions of the soybean
plant grown in farm soil with cerium dioxide and zinc oxide nanoparticles,”
conclude the study’s authors. “In addition, our results have shown that cerium
dioxide NPs in soil can be taken up by food crops and are not biotransformed
in soybeans. This suggests that cerium dioxide NPs can reach the food chain
and the next soybean plant generation, with potential health implications.”
See ACS Nano Press Release, February 6, 2013.