Nano Environmental Health and Safety (Nano EHS)At NIEHS, a unique combination of knowledge, expertise, and a commitment to understanding the role of environmental exposures in human disease enables a novel approach to the study of nanomaterials and their potential effects on human health. This field is known as Nano Environmental Health and Safety, or Nano EHS. The critical research challenges for investigating nanoscale materials — determining dose, assessing biological response, and quantifying exposure and risk — are the same challenges on which NIEHS has built its reputation.