Hello!
I am using SimaPro LCA software with USETox and have some results however I have no idea how to interpret the significance of the results. For example is 1 CTUh a serious human health threat or would it have to be in the order of 1000 CTUh? Likewise for CTUe (eco toxicity). To give an example I have found that the carcinogenic toxicity associated with the system I am studying is 9.0E-07 CTUh over the 50 year lifecycle of the system.
Thanks in advance!
Best regards,
Martin Freney
In our section about frequently asked questions (FAQ), we have listed several comments on how to use and interprete USEtox™ results (see How to use USEtox™ characterization factors). Specifically in the first FAQ entry here, we explain how to interprete the units [CTUh] = [disease cases per kg emitted] and [CTUe] = [PAF × m³ × day per kg emitted].
Whether in your case 9.0E-07 CTUh = 9.0E-07 disease cases per kg emitted chemical(s) over 50 years life cycle of your studied system is relatively high or small depends on many factors including the system dimensions, emitted chemicals, etc.