Good morning,
i am doing a project on true cost accounting (in beef cattle) and they recommended using the USEtox tool for calculating human toxicity. The ranch only used a herbicide (glyphosate), and a fertilizer (urea) but i cant find them on the substance input. I clicked on the direct emission interface.
I would appreciate your help
For using USEtox to derive human toxicity impacts associated with the use of glyphosate and urea, we propose you combine (a) emissions of each of these substances to the air, soil and freshwater compartments on your side with (b) respective USEtox human toxicity characterization factors for these substances, separately for each emission compartment. The product of emission mass into each compartment and the respective characterization factor can then be aggregated per substance to get an overall human toxicity-related impact score.
If you cannot find emission data, you might want to assume as first proxy that 100% of both substances used at the farm reach the soil compartment.
USEtox 2.14 already provides characterization factors for both substances: for results for glyphosate please search the results files for CAS number 1071-83-6, and for urea please search for CAS number 57-13-6.