Exposure Modeling of Nanomaterials in the Environment

As shown previously, ENMs are released from products during use. This knowledge, however, is not sufficient to allow an estimation of the possible environmental risks that these ENMs may pose. The risks of any compound to organisms in the environment is linked to their exposure concentration. Because of the lack of analytical measurements of ENMs in the environment, the expected concentrations in the environment have to be modeled. These modeled concentrations can then be used to evaluate the impact of an ENM or a certain ENM-containing product on the environment. This risk evaluation is needed to rate the impact of a certain ENMs and it also allows different ENM products and applications to be compared. 

Another study used a life-cycle perspective to model the quantities of engineered nanoparticles released into the environment [8]. The ENMs nano-Ag, - 2, and carbon nanotubes (CNTs) were studied. The quantification was based on a substance flow analysis from products to air, soil, and water in Switzerland. The life-cycle of the nanoproducts formed the basis for assessing the mass flows of the ENMs from the products to the environment during the use phase and disposal. The following 

Qo Water, sludge, soil, air UK Different market penetrations of nanoproducts assumed 

8 Tto2, Ag, CNTs Water, air, soil CH All ENM applications and products considered 

54 Ag Water EU Only dissolution of Ag-ENM and release of Ag+ considered, no ENMs modeled 

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