The Proceedings of the National Academy of Sciences (PNAS) posted on its website on August 20, 2012, an article entitled “Soybean susceptibility to manufactured nanomaterials with evidence for food quality and soil fertility interruption.” According to the authors, no single study to date has examined the full implications of growing plants to full maturity in field soil contaminated by manufactured nanomaterials. The PNAS study does so for soybeans in farm soil amended with two metal oxide manufactured nanomaterials. The abstract states: “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-CeO2, plant growth and yield diminished, but also (iii) nitrogen fixation — a major ecosystem service of leguminous crops — was shut down at high nano-CeO2 concentration.” The authors conclude that, “[j]uxtaposed 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” manufactured nanomaterials.
