A study examining the potential for human inhalation of nanoparticles through the use of nanotechnology-based cosmetic powders indicates that the predominant deposition of these particles would occur in the tracheobronchial and head airways rather than in the lungs.
The study, conducted by researchers at Rutgers University and published in Environmental Health Perspectives, concludes that this deposition of nanoparticles could potentially lead to different health effects than those investigated in previous studies of nanoparticle behaviour and toxicology that have primarily focused on nanoparticles’ effects on lung health.
They note that the observed effect may be occurring because the particles in the tested cosmetics products tended to be larger or to agglomerate, whereas smaller particles would be more likely to penetrate lungs. The authors note that to the best of their knowledge, this is the first study to determine the human inhalation exposure potential for nanomaterials released from cosmetic powders “in a realistic exposure simulation".
The study characterised cosmetic particles using a mannequin to simulate product application. It compared the inhalation potential of several commercially-available cosmetic products with and without nanoparticles, including: a blusher, a moisturiser, and a loose-powder sunscreen. Given the apparently strong potential for inhalation exposure, the researchers recommend exposure assessment studies for such products and a requirement that manufacturers report the presence of engineered nanomaterials in their products.