A novel social life cycle assessment method for determining workers' human development: a case study of the sugarcane biorefineries in Brazil.

Purpose: The social life cycle assessment (S-LCA) methodology needs to advance in its methodological development, mainly regarding the impact assessment phase, in which a widely accepted method is missing. The goal of this study is to introduce a social metric to evaluate the human development of workers in production chains and economic sectors. Methods: The applied characterization model of the proposed social metric was inspired by the Human Development Index (HDI), whose significance and wide use make it a good proxy to express human prosperity. Similar to HDI, our indicator called Workers' Human Development Index (W-HDI) is derived from the geometric mean of the three dimensions of HDI, covering education, income, and health aspects of workers in different economic sectors linked to a given production chain. W-HDI proposal was tested by performing a case study from the sugarcane industry in Brazil, considering different sugarcane biorefinery configurations, including a couple of first-generation ethanol options and an integrated first- and second-generation ethanol production system (1G2G). Results and discussion: The proposed metric was used to address the social impacts of different biorefinery scenarios. The scenario representing the first-generation ethanol production with basic technology achieved the lowest W-HDI score mostly because of the manual sugarcane harvesting system that contributed to a higher rate of occupational accidents (lower health dimension), fewer years of education, and lower wages than the other biorefinery scenarios. The highest W-HDI was obtained by the 1G2G scenario, mainly due to a more advanced technology reflected by the higher educational profile (more years of schooling) required to the workers and better wages. Additionally, our proposed W-HDI was applied in the assessment of Brazilian economic sectors, and most of them (84%) obtained medium or high development levels. Conclusions: The present study contributes to the development of sustainability assessment tools by providing advances in the social life cycle assessment methodology. More specifically, the W-HDI is proposed to address the impact assessment phase with an indicator that can be applied in many sectors and production chains. [ABSTRACT FROM AUTHOR]