Scientists close to nanotechnology research on human health and environment have concluded that the technology's effects are not well understood, according to a recent literature review published in the Journal of Agricultural and Food Chemistry. But this hasn't deterred the Environmental Protection Agency (EPA) from pushing forward to regulate and oversee nanoagriculture.
A team of chemists at the University of Texas at El Paso set out to understand how nanoparticles amass on plants and if that creates problems for the plants and those who eat them. The particles' small size—think 25,400,000 nanometers in an inch—may allow them to pass through cell membranes or the blood-brain barrier, possibly resulting in unintended effects, said the EPA.
But EPA also states that the use of nanoscale materials in pesticide products may have positive potential. Nanoagriculture could allow for "more effective targeting of pests, use of smaller quantities of a pesticide and minimizing the frequency of spray-applied surface disinfection," according to the agency.
So far, the scientific evidence points to more questions than answers. The nanotechnology in agriculture review found that "very few studies have been conducted on the genetic response rendered by the nanoparticles on edible plants." Various factors influence toxicity of a plant, and the scientists concluded that no general toxicity trend could be found.
However, researchers cautioned that most of the studies observed physiological and visual toxicological effects, and that toxicity also should be studied at the proteomic, genomic and metabolic levels.
The review included studies and recent publications on the absorption, translocation, accumulation, and biotransformation of engineered nanomaterials in edible plants, such as soybean, pumpkin, alfalfa and corn.
U.S. government steps up nanotechnology review
Although there have been statements made regarding the development of nanoscale materials for agricultural applications, an EPA spokesperson said it has not approved any such an application.
Under the Federal Insecticide, Fungicide, and Rodenticide Act EPA seeks to evaluate both existing and new uses of nanoscale pesticides. If a pesticide using nanotechnology will be used on plants, then data for its effects may be required, said an EPA spokesperson. The EPA grants registration for pesticides provided that:
- The product's composition warrants its proposed claims
- The product's labeling, and other material required to be submitted, comply with FIFRA
- The product will perform its intended function without causing unreasonable adverse effects on the environment when used in accordance with widespread and commonly recognized practice
EPA also seeks to obtain information about what nanoscale materials are being introduced into commerce and to require companies to inform the agency before they produce new types of nanoscale materials. Data is also being collected on nanoscale materials already in production under the Toxic Substances Control Act reporting rule.
At this time, the agency reported it does not have a time frame for issuing a final policy.
Nanotechnology regulation beyond agriculture
Nanoagriculture is just one facet of a greater governmental focus on nanotechnology use. In June the White House announced a framework for regulating and overseeing nanotechnology use [PDF].
The National Nanotechnology Initiative (NNI), a top science and technology priority for the Obama Administration, already has invested almost $14 billion in research and development since 2001. The NNI's key goal is "the responsible development of nanotechnology, which requires maximizing the benefits of nanotechnology while understanding and managing the relevant risks," according to the report.
Other agencies also are involved in the effort. For example, the FDA recently released guidance about nanotechnology for FDA-regulated products such as sunscreen and dietary supplements.
