Range-Finding Risk Assessment of Inhalation Exposure to Nanodiamonds in a Laboratory Environment

Delivered dose was calculated by using the In vitro Sedimentation, Diffusion and Dosimetry (ISDD) model developed by Hinderliter et al. [1]. The ISDD model is based on the general dynamics of particles in viscous media where mass transfer is driven by diffusion and sedimentation [2–4]. Because environmental conditions in in vitro—experiments are homogenous, advection is assumed to be negligible. The model is designed for primary particles and agglomerates which do not interact with each other, and thus the model does not take into account agglomeration during the simulation. For fractal particles, the model assumes that agglomerate pores are uniformly filled by the media and there are no flows through the agglomerate. Agglomerate behavior in viscous media in the ISDD model is described by Sterling et al. [5]. The ISDD model to calculate delivered dose of agglomerated particles requires the following parameters: temperature T (K), media density (g·cm −3 ) and viscosity μ (Pa·s), media height h (m), ND hydrodynamic agglomerate size in the test media dH (m), ND primary particle size d (m) and density ρp (g·cm −3 ), packing factor PF (–) and fractal dimension DF (–).