A release of engineered nanoparticles into the environment may occur during the production process, as waste or during the usage of products. Nanoparticles can get into the air, into water bodies as well as into the soil. (Fig. Flowchart) Besides plants, which get into contact with nanoparticles via soil and water over their roots or via the air over their leaves, one also has to consider many micro organisms such as bacteria or fungi. The latter have important functions within the ecosystem and can be exposed to particles via soil, air and water. After all, a number of organisms such as worms in soil or water organisms are exposed only via one environmental compartment. For all the other organisms, such as for humans, the air is the most important route of entry. In this context it is important to differentiate between engineered and natural occurring nanoparticles, the latter arising from combustion processes (volcanoes, forest fires) or the weathering of rock by wind and rain. These nanoparticles represent natural components of our environment and humans, animals and plants are adopted to an exposure for a long time.
Engineered nanoparticles, however, are an altogether novel challenge. It is difficult to measure (analyze) these really tiny particles. The instruments required are very expensive and are not yet even able to measure accurately anywhere in the environment. Therefore, different projects funded by the Federal Government and the European Union have been dedicated to the development of methods and instruments that allow a reliable and exact measurement of nanoparticles in workplaces or in the environment.