The dynamic development of nanotechnology and the use of a variety of nanomaterials in many areas of activities and daily life products creates the possibility of emissions of dangerous “nanocontaminants” to the environment. Nanomaterials can be released into the environment at every stage of the product life cycle. The toxicity of nanomaterials is related to their specific physical and chemical properties. Evaluation of the potential environmental risks requires precise and conclusive data on nanomaterial toxicity, their emissions, information on the fate of nanomaterials in the environment and possible exposure levels.