A proposal for the derivatization of characterization factors for CdTe Quantum dots that integrates changing particle sizes throughout their life cycle

Authors
Blázquez Sánchez, Maria; Ligthart, Tom; Corral, Beatriz; Rosenbaum, Ralph; CAJARAVILLE, Miren P.

Abstract
Even if it has been claimed that Life Cycle Assessment (LCA) is an essential tool to analyse, evaluate, understand and manage the environmental and health impacts of nanotechnology, few studies incorporate characterization factors (CFs) for human toxicity and freshwater ecotoxicity of engineered nanomaterials (ENMs) beyond their manufacturing stage. The USEtox® model , which is the UNEP-SETAC consensus methodology to derive characterisation factors for freshwater ecotoxicity and human toxicity to be used in Life Cycle Impact Assessment (LCIA). In the present work the USEtox® model (which is not nanospecific) and the SimpleBox4Nano , model (which accounts for nanospecific processes, e.g. aggregation, and dissolution for fate derivatization) have been combined to derive CFs for a nanomaterial. The suitability of the proposed approach has been assessed in an ENM case study on polyethyleneglycol-coated cadmium telluride (PEG-CdTe) quantum dots (QDs). Existing information on the (eco)toxicological impact of this ENM was used for EF derivatization. A range of sizes representative of different life cycle stages of PEG-CdTe QDs were defined and experimentally derived. Combining the two selected models was done by alignment and resulted in CFs for three different size classes for both for freshwater ecotoxicity and human health impact. The approach hereby proposed allows to derive size-specific CFs for ENMs beyond the manufacturing stage to be used in LCIA.