Researchers at the National Institute of Standards and Technology (NIST) and the University of Massachusetts Amherst (UMass) have provided the first evidence that engineered nanoparticles are able to accumulate within plants and damage their DNA. In a recent paper, the team led by NIST chemist Bryant C. Nelson, showed that under laboratory conditions, cupric oxide nanoparticles have the capacity to enter plant root cells and generate many mutagenic DNA base lesions. This research is part of NIST's work to help characterize the potential environmental, health and safety (EHS) risks of nanomaterials, and develop methods for identifying and measuring them. Cupric oxide is a strong conductor of electric current, a property enhanced at the nanoscale level, which makes the nanoparticle form useful to semiconductor manufacturers.