Comparative modeling of exposure to airborne nanoparticles released by consumer spray products

Abstract

Consumer exposure to sprays containing nano-objects is a continuing concern as a potential health hazard. One potential hazard has been formulated in the overload hypothesis. It describes a volume fraction of the macrophages that is occupied by deposited nanoparticles that leads to reduced macrophage mobility. Subsequent chronic inflammation may then lead to severe health consequences including cancer. To calculate lung deposition of spherical particles, the Multiple-Path Particle Dosimetry (MPPD) model (ARA, Albuquerque, NM) provides different kinds of lung models and age settings. Using the MPPD v 2.11 software, we modeled several consumer-related exposure scenarios. Different body orientations and age groups were investigated. Moreover, a number of materials representing different densities were used, and the exposure calculated using MPPD is compared to the hazard derived from the overload hypothesis. Conditions leading to macrophage overload were found for exposures to high particle doses for prolonged times and repeated exposure. Such conditions are unlikely in the context of regular consumer exposure. The overload hypothesis assumes the particles to be inert and biopersistent, a condition that currently lacks a clear regulatory definition and is valid only for a few selected materials. Furthermore, because of material-specific effects and the possibility of surface adsorption of hazardous chemicals, nano-objects in propellant sprays remain of concern for consumer health.

• Consumer spray products
• exposure modeling
• nanoparticle
• overload hypothesis

Acknowledgements

We would like to thank Anja Köth, Heinz Kaminski and Thomas Kuhlbusch for their involvement in research leading up to data related but not discussed in this study.

Declaration of interest

The authors declare no conflict of interest.

This study was supported by the German Federal Ministry of Education BMBF, nanoGEM Project, FKZ 03X0105. Parts of the data have been discussed and are published in the final report of the nanoGEM project (see: www.nanogem.de).

Supplementary material available online

Supplementary Tables 1, 2, 3 and 4, Figures 1 and 2.