Carbon capture utilization and storage (CCUS) is anticipated to play a key role in the global energy transition by reducing greenhouse gas emissions in numerous industries. Life cycle impact assessment (LCIA) is a decision-making tool that has been widely adopted in CCUS research. Although the focus of LCIA has been predominantly on climate change, other impacts including human health are influential. However, published LCIA conclusions on human health impacts are highly uncertain.

We performed a targeted review of publications in the peer-reviewed literature (2008-2023) that included human health as an impact factor in LCIA of post-combustion carbon capture (CC) technology using aqueous amines as the capture solvent. Data extracted from publications included: LCIA method, impact categories, emissions inventory, and methods for derivation of human toxicity potential (HTP). The purpose of the review was to explore the range of approaches and findings related to human health impacts of the CC technology and identify foundational data driving those impact scores.

Out of 82 publications, only 34 included HTP as an endpoint. For each of the publications, a summary of the selected emissions and characterization factors used to evaluate cancer and non-cancer impacts within the LCIA is presented. The respective data sources for each factor were reviewed to identify whether the underlying assumptions in both the LCIA method and the emissions inventories were accurately assessed and applied. Results indicated that the solvent monoethanolamine (MEA) was commonly chosen to characterize toxicity and assessed through either ethanolamine production or CO₂ production, with its characterization factors showing variability based on the LCIA method used.

The primary conclusions reached by the authors of the 34 studies were that while a process equipped with CC technology may reduce carbon emissions, solvents associated with amine capture technology pose potential human health hazards. However, the data underlying most studies were associated with high uncertainty. For example, the most widely cited emissions inventory referenced only a single study unrepresentative of full-scale amine CC facilities. Further, the HTP scores for MEA did not reflect MEA specifically and were derived from limited sources. Therefore, if these CCUS LCIA studies are being relied upon to make decisions regarding implementation of this technology, the results should be interpreted with caution.