Toxicologia Ambiental e Analítica

Physicochemical Characteristics of Two Prototypical Home-Use Consumer Products Containing Engineered Nanomaterials

Abstract

Christie M Sayes, Aishwarya Sooresh and Kenith E Meissner

The extensive use of nanomaterials in new products for the building envelope is expanding rapidly and continues to influence materials science and environmental health. However, there is still uncertainly around the safety of these novel materials to humans and the environment; therefore, more life cycle data is needed. One analytical technique to gather information critical to the development of safe nanomaterials is to characterize the physicochemical properties of the nano-enabled product along various stages of the product life cycle. This research investigates two different products fortified with nanoscale titania relevant to the building and construction industry: (1) a white paint and (2) a lacquer formulation. Three brands of commercially available titanium dioxide (TiO2) nanoparticles were incorporated into labformulated paint and lacquer mixtures. These fortified products were subjected to simulated degradation processes (a.k.a. “wear-and-tear” scenarios) to mimic the real world. Unincorporated TiO2, as well as TiO2 incorporated “wornand- torn” powders, were processed and analyzed for physical, chemical, and toxicological characteristics. Electron microscopy confirmed the presence of nanoscale TiO2 particles in the painted and lacquered matrices for all three nanoparticle-types. Cell viability and reactive oxygen species (ROS) generation was measured in immortalized human lung epithelial cells (A549). Results from bioassays showed that ROS generation between unincorporated TiO2 particles and TiO2 incorporated paint powders showed little difference, but, the TiO2 incorporated lacquered powders demonstrated significantly lower ROS generation and cell death. Thus, the polymer-based lacquer mitigated tissue damage. Our results show that using a life cycle approach may help provide data – and by extension, an understanding - of nanomaterial properties in the context of developed consumer products.