A comparative approach to evaluate the toxicity of building materials through life cycle assessment

Background: This paper addresses the lack of research that compares the toxicity of commonly used construction materials. The toxicity of construction materials has received less attention, despite its importance within the Life Cycle Assessment methodology. All aspects, including toxicity, need to be analysed throughout the life cycle of the material to understand its true behaviour.

Aim: The purpose of this study is to propose a methodology to compare the toxicity of different construction materials and highlight the need to consider toxicity criteria in the selection of materials during the design phase. The study seeks to fill the gap in the existing literature by providing information on the comparative toxicity of the most common building materials.

Methodology: The study follows Life Cycle Assessment methodology as established by the ISO 14040:2006 and ISO 14044:2006 standards. For this study, statistics were consulted to identify the most used materials in the construction sector; then, from this group of materials, those available in the Ecoinvent 3.7.1 database were selected. For comparison, these materials were categorised into material families and a functional unit was established to compare them. Finally, all materials were compared with each other, using 1 kg as the functional unit.

Results: When we conduct a comparative analysis of various materials and categorise them into groups, it becomes readily apparent which materials demonstrate a less favourable performance with respect to their toxic properties. This approach allows us to discern and pinpoint those materials that present a more concerning level of toxicity relative to others, facilitating informed decision-making in terms of construction material selection and design.

Conclusions: By comparing all materials with each other using 1 kg as the functional unit, we can conclude that some materials have a greater impact than others, both in absolute and relative terms, for example, steel and polyurethane foam.