Secondly, applying a cut off to inventory may imply the exemptions of some chemicals from emissions profile and the underestimation of possible toxic effect (either ecotox or human tox). E.g. Methylchloroisothiazolin is a component of the Isocide C, an ingredient which was excluded due to cut-off. However, in USEtox, it has CFs for ecotoxicity which are quite high. Indeed, CFs span from 4.73E+3 CTUe for emission into air, to 1.61E+4 CTUe for emission into soil, up to 5.44E+04 CTUe for emission into water.
Finally, as for other LCA involving chemicals, the impact of the mixture of chemicals in the different life cycle stages is not evaluated. This could lead to underestimation of the magnitude of toxicity related impact as, in reality, some emissions occur simultaneously in water/air.
In conclusion, referring to the goals of the analysis (see Section 2.1), the study evaluates the environmental performance of bio-based ingredients in order to support the better option and to avoid the risk of burdens shifting. The possibility of increasing the relevance of LCA in helping designing green chemistry and ecoinnovation is also related to data availability. Therefore, it is of uppermost importance to improve the availability of LCI data for fine chemicals and especially cosmetic ingredients.
Appendix A. Supplementary data
The following is the supplementary data related to this article: