Principles and indicators for assessing the environmental dimension of sustainability within green and sustainable chemistry

In this current opinion, we travel through the evolution of the principles and indicators to assess environmental sustainability of chemical products and processes. Although the first ones were developed within Green Chemistry to account for the green characteristics of a chemical product/process, they are unable to quantify sustainability of that product/process, since they are more focused on synthetic aspects. These limitations, concurrently with the ever-greater pervasiveness of Sustainable Development, led to the development of more comprehensive principles, metrics, and indicators able to assess possibly all the phases of a chemical product/process life cycle, thus quantifying its environmental impact in a holistic manner, thus its belonging to Sustainable Chemistry (SC). This current opinion overviews these metrics/indicators limitedly to the environmental dimension of green and SC. Finally, the potentialities of selected metrics in covering the quantitative assessments of chemical products and processes circularity and their contributions to the seventeen Sustainable Development Goals, are highlighted.