Higher transparency: A desideratum in environmental life cycle assessment research

Abstract

Transparency in reporting of Life Cycle Inventory (LCI) data and disclosure of analysis scripts of an environmental Life Cycle Assessment (LCA) model are important as they serve to provide the core evidence underpinning scientific claims. In this study, a transparency assessment was conducted against 438 recently published LCA research. Primary LCI data are frequently disclosed for the majority of the research examined (n = 419, 96%), while a full list of secondary LCI data is only available for one third of the research (n = 152, 35%). The lowest transparency is found in the disclosure of the analysis scripts of LCA models, with only seven research (<2%) providing the information. The adoption of open-source programming languages has the highest potential for improving the data and model transparency and the reproducibility of an LCA. Based on one of the most widely adopted secondary LCI databases, ecoinvent database, the Global Warming Potential of 5280 activities of the 740 unique reference products was calculated. High within-product variations are observed for selected activities, suggesting the need for full disclosure of secondary data applied in an LCA to support the interpretation of its results. Provision of justification on the selection and adaptation of secondary LCI datasets, which is usually not given in the research reviewed, is also highly recommended. With a relatively higher weighting given to the disclosure of secondary datasets, a new “SEARI” scoring system for assessing data and model transparency is proposed, aiming to contribute to the progressive improvement in transparency of LCA studies.