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Abstract Materials production is a primary driver of anthropogenic greenhouse gas emissions; yet the externalized costs of these emissions on society are not reflected in market prices. Here, we estimate the externalized climate costs from materials production in the United States at approximately 79 billion USD per annum, and we highlight disparities in materials pricing. Proper accounting for such disparities can be leveraged to drive breakthroughs in technologies used for our material resources and manufacturing. 

Abstract The construction and building materials (CBM) production industries, such as cement, steel, and plastics that are responsible for a substantial share of global CO₂emissions, face increasing pressure to decarbonize. Recent legislative initiatives like the United States (US) federal Buy Clean Initiative and the World Green Building Council’s decarbonization plan for Europe highlights the urgency to reduce emissions during CBM production stages. However, there remains a gap in addressing the localized environmental and social impacts of these industries as well as a necessary understanding of how decarbonization efforts may change local impacts. This study introduces a framework for quantifying the disproportionate impacts (I_d) of 12 CBM production facility categories on communities of color and low-income demographics across the US. Using geographical and environmental data from the 2017 National Emissions Inventory (NEI), we assess these impacts at four spatial scales: census tract, county, state, and national. Results show that across all scales, many CBM production facilities impose disproportionate impacts. The geographical disproportionate impact (I_G,d) shows the greatest burdens at the broadest spatial scales, whereas the environmental disproportionate impact (I_E,d) indicates highest burdens at more localized levels. Based on this spatial understanding, we provide methods that can be implemented to support community engagement and mitigate damages to populations neighboring industrial materials manufacturing. These findings offer valuable insights into the relationship between facility locations, emissions, and demographic groups, providing a basis for more targeted environmental justice policies aimed at mitigating these disproportionate impacts. 

Abstract Growing urban populations and deteriorating infrastructure are driving unprecedented demands for concrete, a material for which there is no alternative that can meet its functional capacity. The production of concrete, more particularly the hydraulic cement that glues the material together, is one of the world’s largest sources of greenhouse gas (GHG) emissions. While this is a well-studied source of emissions, the consequences of efficient structural design decisions on mitigating these emissions are not yet well known. Here, we show that a combination of manufacturing and engineering decisions have the potential to reduce over 76% of the GHG emissions from cement and concrete production, equivalent to 3.6 Gt CO₂-eq lower emissions in 2100. The studied methods similarly result in more efficient utilization of resources by lowering cement demand by up to 65%, leading to an expected reduction in all other environmental burdens. These findings show that the flexibility within current concrete design approaches can contribute to climate mitigation without requiring heavy capital investment in alternative manufacturing methods or alternative materials. 

Fiber-reinforced concrete (FRC) can have improved durability and tensile properties, potentially enabling the more efficient use of concrete and lowering greenhouse gas (GHG) emissions. Yet, systematic quantifications of the environmental impacts of FRC, particularly when paired with changes to mechanical properties and the implications for material longevity, are limited. Herein, an assessment following the life-cycle assessment methodology for four common FRCs was performed, namely, those reinforced with polyvinyl alcohol (PVA), steel (ST), polypropylene (PP), and polyethylene terephthalate (PET). The analysis was bound to a cradle-to-gate scope, and solely virgin fiber material production was considered for the environmental impacts. Coupled changes in compressive and tensile strength, environmental impacts, and the role of material longevity and cost relative to unreinforced concrete were examined. Findings from this work show that, similar to unreinforced concrete, cement remains a key source of GHG emissions in FRC production. However, in FRCs fibers can drive additional emissions by up to 55%. Notably, PVA and ST led to the highest impacts and costs, which were minimal for inclusions of PP and PET. Yet ST contributed to the greatest benefits in flexural and compressive strengths. When the effects of longevity were integrated, FRC with PP reinforcement could offer desired emissions reductions with minimal increase in use period and cost, but the other fiber reinforcements considered may need to offer longer service life extension to reduce emissions compared with conventional concrete. These results indicate that FRC can enhance mechanical performance, but fiber type selections should be informed by the design life to achieve actual GHG emissions reductions. 

Achieving net-zero greenhouse gas emissions likely entails not only lowering emissions but also deploying carbon dioxide (CO₂) removal technologies. We explored the annual potential to store CO₂in building materials. We found that fully replacing conventional building materials with CO₂-storing alternatives in new infrastructure could store as much as 16.6 ± 2.8 billion tonnes of CO₂each year—roughly 50% of anthropogenic CO₂emissions in 2021. The total storage potential is far more sensitive to the scale of materials used than the quantity of carbon stored per unit mass of materials. Moreover, the carbon storage reservoir of building materials will grow in proportion to demand for such materials, which could reduce demand for more costly or environmentally risky geological, terrestrial, or ocean storage. 

Globally, the production of concrete is responsible for 5% to 8% of anthropogenic CO2 emissions. Cement, a primary ingredient in concrete, forms a glue that holds concrete together when combined with water. Cement embodies approximately 90% of the greenhouse gas emissions associated with concrete production, and decarbonization methods focus primarily on cement production. But mitigation strategies can accrue throughout the concrete life cycle. Decarbonization strategies in cement manufacture, use, and disposal can be rapidly implemented to address the global challenge of equitably meeting societal needs and climate goals. This review describes (a) the development of our reliance on cement and concrete and the consequent environmental impacts, (b) pathways to decarbonization throughout the concrete value chain, and (c) alternative resources that can be leveraged to further reduce emissions while meeting global demands. We close by highlighting a research agenda to mitigate the climate damages from our continued dependence on cement. 

Here, we show production pathways for greenhouse gas (GHG)-negative bio-based plastics from 2nd and 3rd generation feedstocks. We focus on bio-based plastics that are technically capable of replacing 80% of the global plastic market. By presenting life cycle inventories and discussing GHG-emissions hotspots, this work will inform stakeholders along the plastic supply chain of the necessary steps to achieving net-zero emissions by 2050, and potentially, how to drive net-uptake. This work is of critical importance given the overwhelming mass of plastic produced annually and the resulting CO2 emissions. To conduct this assessment, we derive life cycle inventories for nine different bio-based plastics and address the impact of methodological choices, such as allocation method, on the resulting 100a global warming potential (GWP). Our findings show that resources used and processing methods implemented have significant effects on the potential for us to derive carbon-negative plastics. Furthermore, we find that environmental impact quantification methods greatly influence the perceived GWP of such processes. For example, economic and mass allocation methods resulted in an apparent increase in GWP of up to 39% and 166%, respectively, compared to no allocation for bio-based plastics made from 2nd generation crops, whereas mass allocation resulted in the lowest GWP for bio-based plastics made from 1st generation crops. In considering environmental impact hotspots, our findings show that decarbonization of thermal energy and electricity, reduced use of ammonia-based fertilizer, renewable hydrogen production, use of bio-based alternatives for petrochemicals and plasticizers, enzyme production pathways from 2nd generation crops, and more efficient biomass conversion processes to reduce feedstock inputs may be critical steps in creating GHG negative bio-based plastics in the future.