ABSTRACT
Life-cycle impact assessment (LCIA) makes the link between the life-cycle inventory, which catalogues all relevant pollutant-emissions, and how those inventory items contribute to various environmental and human health impacts. Specifically, for toxicological impacts, there are a series of consideration from the point of emission to the ultimate uptake and damage at a receptor (i.e. human organ) that, in itself, is a quite rigorous exercise involving many different disciplines such as chemistry, biology, geosciences, and toxicology, for example. Thus, the history and development of LCIA models for toxicity impacts has always been about the trade-off between competing specializations, the accuracy of the resulting impact values and the feasibility of implementing the amount of details required in accounting for all relevant parameters. In the case of engineered nanomaterials (ENM), there has only been very limited cases of development of fate, transport, exposure and toxicity modeling in LCA for such emissions. In most cases, rule-of-thumb or generic assumptions were made to make such models fit with existing ones for organic chemicals. However, ENM behave quite differently than their organic counterparts and, in particular, are most appropriately addressed using dynamic modeling assumptions. This chapter explores the use of dynamic fate and exposure models in order to define the relevant human health toxicity characterization factors needed to for an LCIA.
