An Integrated Approach to Meet NanoEHS Challenges Along the Life Cycle of Nano-Enabled Products: The Case Study of Engineered Nanoparticles Emitted from toners used in Printing Equipment

D. Bello, P. Demokritou
University of Massachusetts Lowell, US

Keywords: nano-enabled product, dosimetry, integrated approach, printers

Summary:

A large number of engineered nanomaterials (ENM) are already in use in different nanotechnology sectors as well as consumer and personal care products. Populations of workers and consumers are being exposed to ENM across the life cycle (LC) of nano-enabled products (NEPs), during synthesis, consumer use, and at the end of life. Harnessing the potential of any nanotechnology application requires careful balancing of benefits against potential risks. In this context, science-based assessment of potential adverse effects and risks is critical. Currently, the risk assessment paradigm used in nano toxicology is based on the toxicological properties and exposures of bulk ENMs at the occupational level. Toxicological and risk assessment along the life cycle of NEPs presents several unique challenges compared to primary production of bulk ENM in occupational settings: (i) Little is known about realistic exposures per se across LC; (ii) Scenarios are scattered across LC; (iii) The physicochemical and morphological (PCM) properties of emitted particles are usually significantly different from the input nanomaterials used in the synthesis; (iv) As a result, toxicological properties of actual particle exposures are often unknown (and so is the hazard and risk) and cannot be inferred from that of input ENMs used in the synthesis of NEPs. We present here an integrated and structured approach to address the needs of science-based hazard and risk assessment across the LC of NEPs. We illustrate the approach with a case study of an NEP widely used by almost everyone: consumer and workplace exposure to engineered nanoparticles from toners used in printing equipment. This approach is suitable for other similar scenarios such as mechanical processing of advanced composites containing carbon nanotubes and other ENM, and end-of-life incineration of such composites.