Understanding the detailed material composition of the various industrial and consumer products is essential for implementing efficient recycling practices and policies, conducting material flow analyses, and facilitating a transition toward a circular economy. However, existing data sources are limited in their product and material coverage. Currently, no source or methodology allows such data to be obtained in a relatively uniform, updated, and accessible manner across a diverse range of products. This work presents an approach that allows estimating the material composition of thousands of products using available life cycle inventory (LCI) databases. Methodologically, this is implemented by splitting the physical flows that describe supply chains in LCI databases into “incorporated” and “not incorporated” fractions using an incorporation parameter. Building primarily on existing matrix-based life cycle assessment calculations, this approach can be used to calculate the material content of products. A generally applicable mathematical model, as well as a ready-to-use software, is presented for future practitioners. To demonstrate the robustness of the proposed method, a case study involving three metals and plastic in three consumer goods has been conducted based on the ecoinvent database. Our method delivered accurate material content estimates (i.e., weight fractions of materials in products) with an average relative error of 26% and an absolute error of 1.1% (between our estimates and existing values). ... Read more

Data on the total product lifetimes, which is much needed in the fields of sustainability and circularity assessment, is currently sparse and challenging to measure. To meet such data and methodological needs, the first information system of its kind has been developed as part of this research. While an online portal collects and stores consumer reports on use and disposal patterns for various electronics owned and used, the harvested survey data was automatically fed into a novel stochastic model that allowed estimating the total lifetimes and durability of the different products considering the impacts of second-hand use. This was done without reliance on auxiliary market statistics and costly facility-based analysis while preserving a satisfactory degree of accuracy. Additionally, the structure of the collected data allows for measuring the effects of the different circular practices (repair, reuse, recycling, etc.) on product longevity which is of specific interest to researchers and policymakers. ... Read more