Comparative analysis of scientific papers on LCA applied to nanoparticulated building materials

Received: 7 December 2024 Revised: 27 May 2025 Accepted: 28 May 2025 Published: 30 May 2025 Citation: Sánchez-Burgos, M.A.; Blandón-González, B.; Conradi-Galnares, E.; Porras-Pereira, P.; Mercader-Moyano, P. Comparative Analysis of Scientific Papers on LCA Applied to Nanoparticulated Building Materials. Constr. Mater. 2025,5, 37. https://doi.org/10.3390/ constrmater5020037 Copyright: © 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/ licenses/by/4.0/). Article Comparative Analysis of Scientific Papers on LCA Applied to Nanoparticulated Building Materials Marco Antonio Sánchez-Burgos, Begoña Blandón-González , Esperanza Conradi-Galnares , Paula Porras-Pereira and Pilar Mercader-Moyano * Department of Building Construction I, Higher Technical School of Architecture, University of Seville, 41012 Seville, Spain; [email protected] (M.A.S.-B.); [email protected] (B.B.-G.); [email protected] (E.C.-G.); [email protected] (P.P.-P.) *Correspondence: [email protected] Abstract: Nanomaterials have emerged as versatile components revolutionizing diverse industries, yet their environmental and health impacts remain insufficiently explored. This paper delves into the latent hazards accompanying their evolution and integration, particularly within the construction sector. It addresses the critical gap in assessing their life-cycle impacts, emphasizing the necessity of explicit reporting on nanoparticle emissions. Employing a Life Cycle Assessment (LCA) approach, this research evaluates the sustainability of nanomaterial applications. The absence of nanoparticle-specific data in existing product databases underscores the need for comprehensive life-cycle emission reporting. Since direct impact calculations remain unfeasible, incorporating predicted emissions and risk assessments into LCA studies is recommended. This study advocates for incorporating nanoparticle risk evaluations into LCA methodologies to enhance sustainability and environmental safety. By prioritizing precise emission data and predictive risk analysis, it advances nanomaterial environmental assessments, contributing to the responsible implementation of nanomaterials in construction. Keywords: Life Cycle Assessment; building materials; nanoparticles; sustainability; construction; sustainable development 1. Introduction The correlation between the construction industry and its environmental impact has been extensively debated. Even though it is vital to fostering social and economic development, its processes have significant environmental effects [1]. The industry comprises several stages, including mining, manufacturing, construction, use, and demolition, with each phase having significant adverse impacts on the environment, consuming substantial amounts of energy, and emitting considerable amounts of pollutants [1]. Energy usage occurs directly during the construction, utilization, and demolition processes, as well as indirectly through the embodied energy involved in manufacturing building materials [ 2 ]. In accordance with a report from the United Nations and other recent studies, the construction industry stands out as the primary contributor to greenhouse gas emissions, comprising almost 38% of the total global CO 2 emissions [ 3 ]. Breaking down this statistic, buildings contribute to approximately 27% of CO 2 emissions associated with operational energy, excluding materials [ 4 – 6 ]. Recent data indicate that construction activity in most major economies has returned to pre-pandemic levels. Consequently, the Constr. Mater. 2025,5, 37 https://doi.org/10.3390/constrmater5020037 Constr. Mater. 2025,5, 37 2 of 19 energy demand in buildings has increased by approximately 4% relative to the previous period, marking the largest annual rise observed in the past decade [4]. As stated above, the importance of buildings in climate change mitigation stems from their considerable impact on greenhouse gas emissions and the rising domestic energy demand at the global level [ 7 ]. Although the building sector’s pivotal role in addressing climate change challenges is widely recognized, only minimal structural modifications have been implemented to reduce energy consumption or lower emissions [ 4 , 8 – 10 ]. While there has been some progress in policy development, the absence of meaningful structural changes underscores the widening gap between the sector’s climate performance and the required decarbonization pathway [4]. In an effort to reduce the environmental impacts of the industry, the focus of research and development has shifted toward the use of sustainable building materials as a means of achieving sustainable construction. In light of escalating concerns regarding environmental issues and the mounting pressure from governmental entities and environmental advocates, numerous studies have focused on minimizing energy consumption and the environmental footprint of buildings [11]. For certain industrial applications and consumer products, manufactured nanomaterials offer numerous advantages over conventional options, such as minimizing the need for raw materials and/or energy [12,13]. Nanomaterials (NMs) are defined as any intentionally manufactured material containing particles that, for 50% or more of the particles in the number size distribution, have one or more external dimensions in the size range of at least 1 to 100 nm. These materials gained significance when researchers discovered that particle size can impact the physiochemical properties of a substance, such as its optical characteristics [14]. Despite their promising applications, many uncertainties remain regarding MNMs, especially with regard to their potential environmental and human health risks if they are released into the environment. MNMs can be released during any phase of their life cycle, from the production and manufacture of nanoproducts to their use and eventual disposal. A thorough understanding of these potential releases throughout the entire life cycle, as well as their potential consequences, is essential for ensuring the safe and sustainable utilization of these materials. Therefore, life-cycle thinking is essential for effectively mitigating the potential consequences of MNM releases [13,15]. The LCA method is widely recognized as a systematic tool for evaluating the environmental impact of building materials and construction processes. It quantifies material flows and analyses their interactions with the environment, while also identifying opportunities for environmental improvements [ 16 – 18 ]. As an internationally recognized framework applied across a wide range of fields, including construction, LCA enhances sustainability by providing insights into the environmental footprint of products and processes [19,20]. By integrating LCA, designers, engineers, and decision-makers can make informed choices, considering environmental impacts rather than relying solely on initial costs [ 21 ]. LCA assesses the environmental footprint of a product from cradle to grave, categorizing emissions into various impact categories, such as climate change, acidification, eutrophication, resource consumption, and toxicity [ 22 – 24 ]. As shown in Figure 1, LCA is an iterative process and involves four main steps [24]: 1. Goal and scope definition: The goal and scope definition phase outlines the purpose of the study, the rationale for conducting the analysis, and other technical aspects, such as the impact categories, the system boundary (both geographical and temporal), and the functional unit for the analysis, are determined [18,25]. 2. Inventory analysis: The second phase, referred to as the Life Cycle Inventory (LCI), entails gathering data or compiling an inventory of all inputs (such as raw materials Constr. Mater. 2025,5, 37 3 of 19 and energy) and outputs (such as waste and emissions) across the product’s entire life cycle (Figure 2). The data collected are essential for calculating the environmental impact of the product. This inventory analysis phase is both the most iterative and time-intensive step in the LCA process [18,25]. Figure 1. LCA framework. Figure 2. Inputs and outputs over a product’s life cycle. 3. Impact Assessment: This third phase, also known as the Life Cycle Impact Assessment (LCIA), focuses on evaluating the potential environmental consequences originating from the inputs and outputs quantified during the inventory analysis phase, as well as the estimated resource usage. The impact assessment is achieved by translating the Constr. Mater. 2025,5, 37 4 of 19 environmental loads into environmental impacts, such as climate change, acidification, eutrophication, etc. [18,25]. 4. Interpretation: In the interpretation step, the focus is on identifying major issues, interpreting the results to draw conclusions, addressing limitations, and providing recommendations from the impact assessment, ensuring that the conclusions are thoroughly substantiated. The standard ISO 14044 provides several checks for data quality and procedures followed during the LCA study to support the conclusions [18,25]. In 1993, a standardization initiative was launched under the International Organization for Standardization (ISO) to improve the interpretation of LCA results. This initiative produced a unified framework and fundamental principles, resulting in standards such as ISO 14040 (1997) for LCIA, ISO 14041 (1998) for Life Cycle Inventory analysis, and ISO 14043 (2000) for interpretation. Presently, the ISO 14044 standard, which was developed in 2006 alongside an updated version of the foundational LCA standard ISO 14040:2006, establishes the standards for LCA [23,26,27]. Undertaking an LCA study for a product or a service involves exploring industrial systems and collecting and analyzing vast amounts of environmental data, which can be an overwhelming task. However, with growing awareness of environmental concerns, a quantitative assessment of impacts has become increasingly relevant [ 21 ]. These environmental concerns can be related to long-term issues such as resource consumption or direct impacts on human health and the natural environment. Clearly, there is a need for structured environmental assessment tools, and LCA is one such tool that is widely acknowledged and accepted for evaluating the environmental impact of products and services. Through LCA studies, a detailed assessment of the environmental impacts associated with particular products across their entire value chain can be obtained [ 21 , 28 ]. In industry, LCA can be applied at the initial stages of product design to identify and possibly mitigate environmental impacts by designing for recycling and/or selecting the materials with lower environmental impact. LCA is also used to communicate the environmental profile of a product to different stakeholders and consumers [19–21]. As industries increasingly adopt LCA, its application has also expanded to advanced materials, including nanoparticulated building materials. With the rapid development and growing use of these materials, assessing their environmental impact through LCA is essential. Addressing this challenge requires a systematic review of the existing scientific literature. Therefore, the following methodology, as outlined in Figure 3, was designed to structure this comparative analysis. This approach addresses key research questions and challenges unfolding at distinct stages throughout the research, ensuring a comprehensive evaluation of LCA’s applications in this emerging field. The methodology in divided into two parts: the introduction section, where the basics concepts are introduced, and the current challenges section, where the main hurdles to address during the investigation are exposed. Both sections are included within the blue dashed circles. Thus, the steps to take are the following: 1. Identification of the problem and contextualization of basic concepts, thoroughly explained in the introduction, to know the origin and the theoretical foundations of nanomaterials, as well as the environmental impact of the current production system. This section will answer two main questions: what nanomaterials are, and how a sustainable building is designed, which are both closely related. 2. Identification of the advantages of LCA, defining its different phases and the challenges in its applicability to nanoparticles. This section will address the primary question of how to evaluate and quantify the environmental impact of a building. Constr. Mater. 2025,5, 37 5 of 19 3. Identification of the advantages that nanoproducts offer in the construction sector, with the purpose of distinguishing materials with specific and advanced properties, thus identifying their environmental and health impacts during the construction process to select the construction materials that incorporate nanoparticles and generate the least impact. This will allow for informed decision-making and the prioritization of materials that align with sustainability and health considerations. Figure 3. Methodology. This section will address the following questions: what advantages advanced materials offer in the construction sector, which trends are present in their use, and what environmental and health impacts their use generates. Along with these aforementioned queries, the diagram presents the conceptual and procedural contents to tackle, encompassed in grey and green circles, respectively, in order to obtain a complete response. The previous points will conclude in the application of an LCA of nanoproducts applied in the construction sector, gathering the conclusions from each phase, and thereby accomplishing the research objective. Following this, each stage of the proposed methodology will be developed. A thorough approach, such as LCA, offers valuable insights into potential environmental concerns and contributes to ensuring the sustainability of nanomaterials. The starting point of this research was identifying nanoparticles and nanoparticle-containing materials used in the construction industry. Following that, standards for impact categories on LCAs and existing LCA databases in the construction sector were identified. Moreover, in order to perform an overall comparative analysis across reviewed papers, a few indicators compiling impact categories were summarized. Finally, the comparative analysis revolves Constr. Mater. 2025,5, 37 6 of 19 around the following four aspects: LCA methodology in use, analyzed impact categories, site boundaries, and scope of assessment. 2. Materials and Methods Sustainable construction processes have been of key importance to the construction industry for the last two decades. The environmental impacts that may result from such processes are of equal importance to the decision-makers. This has led to the quest for the application of life-cycle thinking, with a view to reusing and recycling materials [ 29 ]. Building materials play a crucial role in the construction industry, and the use of sustainable building materials has become increasingly important in recent years. 2.1. Life-Cycle Assessment Fundamentals As previously mentioned, LCA is a widely recognized method to evaluate the environmental burdens associated with a product, service, or process throughout its life cycle, from raw material extraction to final disposal, from cradle to grave, in order to help consumers make environmentally beneficial decisions. The primary objectives of LCA are to quantify or characterize all inputs and outputs throughout the product’s life cycle, specify the potential environmental impacts, and explore alternative strategies to minimize these impacts [30]. In recent years, many countries have introduced normative criteria for the LCA of building materials to regulate their environmental impact. The development of normative criteria can vary depending on factors such as national policies, regulations, and industry practices. Therefore, it is important to conduct comparative studies to understand the differences and similarities in the normative criteria for LCA of building materials in different countries [31]. While ISO standards provide a general framework for LCA, the specific methodology for calculating environmental impacts is not outlined. Depending on the nature of the research, various techniques can be selected, each defined by its environmental mechanisms, as detailed in ISO 14044:2006, which pertains to environmental management, LCA, and the associated requirements and guidelines [31]. Numerous research endeavors have substantiated that LCA studies conducted on complete buildings serve as invaluable instruments for scrutinizing architectural concepts. These studies not only provide a thorough understanding of the environmental consequences related to a building but also play a pivotal role in informing decision-making processes geared towards minimizing ecological footprints. Nevertheless, the LCA methodology has some inherent limitations, requiring careful interpretation and application of the results. In the first place, one challenge is the difficulty of comparing cases, due to unique characteristics such as specific layouts, climate conditions, comfort requirements, and local regulations. A second limitation is the variability in estimated building lifespans. These limitations can be partially addressed by expressing annual impacts per square meter of useful floor space or per person. However, differences in system boundaries, assumptions, detail levels, and LCIA methodologies may still persist [32,33]. As a simplified representation of reality, LCA inherently relies on assumptions that may introduce uncertainties at various levels, such as within the model structure, scenario projections, and parameter uncertainties [ 32 , 33 ]. Processing the first two aspects statistically is challenging and is typically omitted from analyses, but the third can be analyzed due to the presence of data quality indicators for materials and processes in the databases. Parameter uncertainty is often exacerbated by data gaps, leading to less accurate data utilization. Addressing the variability and stochastic errors of the figures improves reliability, although Constr. Mater. 2025,5, 37 7 of 19 interpretation must rely on probabilistic methods. Despite being less conventional, these methods provide valuable conclusions [31]. Throughout the building life cycle, the use phase is the most impactful in terms of environmental burdens, particularly due to its intensive energy consumption. The estimations for this phase rely on average values derived from societal data. The unpredictability of individual inhabitants’ behavior presents a challenge when assessing the reliability of conclusions regarding energy consumption. This unpredictability limits the practical relevance of LCA, regardless of the accuracy of its calculations. Research has shown that many efficiency improvements do not achieve the predicted reductions in energy consumption. The decreased cost of energy services resulting from these improvements typically leads to increased usage. Known as the rebound effect, this psychological behavior has not yet been considered [ 31 , 32 ]. While a stochastic approach incorporating real data could help address this problem to some extent, rebound effects are unavoidable. Economic savings often lead to increased spending in other areas, unrelated to buildings but still environmentally impactful. Moreover, the variability in user behavior and consumption habits, often shaped by regional differences, adds another layer of complexity [20,31]. One of the drawbacks of the current application of LCA in the construction sector is often characterized by an isolated approach to environmental challenges. The analysis often focuses on identifying environmental optima without integrating other critical aspects, such as quality, energy efficiency, structural integrity, or aesthetic considerations. Additionally, although it has been scarcely investigated yet, design has a significant influence on the environmental profile, often having a greater impact than purely technological innovations. Furthermore, financial feasibility is rarely addressed, despite the availability of tools such as life-cycle costing. Despite the development of new regulations and frameworks aimed at evaluating all aspects of sustainability, their implementation remains limited [31]. However, despite certain limitations, LCA remains a highly effective and science-based tool for assessing environmental impacts. 2.2. Nanoproducts in the Construction Sector In recent years, nanotechnology has gained widespread recognition as a prominent concept, thanks to remarkable advancements in the science, engineering, and commercial sectors, including the construction sector [ 14 , 34 ]. The unique physical and chemical properties exhibited at the nanoscale provide remarkable advancements in areas such as (photo)catalysis, thermal and electrical conductivity, mechanical durability, and optical performance. These advancements enable diverse applications, ranging from catalysts and sensors to electronic devices, energy storage systems, and advanced mechanical materials [34]. As a recognized prominent field of study since the last century, nanotechnology focuses on nanoparticles, which are broadly defined as a diverse category of materials featuring particulate substances with at least one dimension below 100 nm [ 14 ]. Additionally, as stated in Commission Recommendation 2011/696/EU, which proposes a revision of the definition of nanomaterials to align with current scientific advancements and practical experience, nanomaterials are defined as “a natural, incidental or manufactured material consisting of solid particles that are present, either on their own or as identifiable constituent particles in aggregates or agglomerates, and where 50% or more of these particles in the number-based size distribution fulfil at least one of the following conditions [35]: a. one or more external dimensions of the particle are in the size range 1 nm to 100 nm. b. the particle has an elongated shape, such as a rod, fibre, or tube, where two external dimensions are smaller than 1 nm and the other dimension is larger than 100 nm. Constr. Mater. 2025,5, 37 8 of 19 c. the particle has a plate-like shape, where one external dimension is smaller than 1 nm and the other dimensions are larger than 100 nm” [35]. Particles with at least two orthogonal external dimensions larger than 100 µ m are excluded from the determination of the number-based particle size distribution. Similarly, materials with a specific surface area by volume below 6 m 2 /cm 3 do not qualify as nanomaterials [35]. For the purposes of this classification, the following definitions are provided for reference: a. “Particle” refers to a minute portion of matter with distinct physical boundaries, excluding single molecules. b. “Aggregate” describes a particle composed of strongly bound or fused smaller particles. c. “Agglomerate” pertains to a group of loosely bound particles or aggregates, with an external surface area comparable to the sum of its individual components [35]. Unlike simple molecules, nanoparticles have a complex structure comprising three layers: a. The surface layer, which is the outermost layer and can be functionalized with various small molecules, metal ions, surfactants, or polymers. b. The shell layer, a material chemically distinct from the core. c. The core, which is the innermost layer and serves as the central structure of the NP, generally identified as the nanoparticle itself [36]. NPs can be broadly classified into various types based on their morphology, size, and chemical properties [ 14 ]. The US Environmental Agency has classified nanomaterials into four types according to their main components: carbon-based nanomaterials, metal-based nanomaterials, dendrimers, and composite nanomaterials. Carbon-based NPs include fullerenes, which have a spherical or ellipsoidal structure, and nanotubes, which are cylindrical. Metal-based NPs cover a range of materials, including quantum dots, gold and silver nanoparticles, and metal oxides such as titanium dioxide. Lastly, dendrimers are polymeric nanoscale particles composed of branched units, characterized by numerous terminal groups on their surface and internal cavities capable of encapsulating other molecules. Composite nanomaterials combine different types of nanoparticles or combine nanoparticles with larger materials [37]. Furthermore, according to the origin of the nanomaterials, they are classified as follows: natural, being produced by trees, plants, volcanoes, or marine species; incidental, when they arise during combustion in vehicles and industrial processes; and artificial, the most common type, produced by two manufacturing processes (top–down/bottom–up). On the one hand, top–down techniques consist of the division of macroscopic material or a group of solid materials until reaching nanometric size. Physical methods, such as grinding or wear, chemical methods, and the volatilization of a solid followed by the condensation of the volatilized components, are utilized until a series of assemblies are obtained, which are precisely controlled until reaching the desired size. On the other hand, bottom–up techniques consist of the manufacture of nanoparticles with the capacity to self-assemble or self-organize, facilitated by the condensation of atoms or molecular entities either in a gas phase or in solution [37]. Due to their exceptional and advantageous properties, including enhanced structural characteristics, functional coatings, and high-resolution sensing and actuating devices, nanoparticles are increasingly applied in various sectors of the construction industry. Nanomaterials in construction, often referred to as manufactured nanomaterials, are those that have undergone manufacturing processes [14,34]. Nanomaterials are incorporated into various construction products, especially in surface coatings, concrete, window glass, insulation, and steel. Furthermore, nanoparticles are gaining popularity in material solutions aimed at the preventive conservation of cultural Constr. Mater. 2025,5, 37 9 of 19 heritage. This is attributed to their anti-degradation properties, which facilitate consolidation, anti-fungal, and hydrophobic activity. Relevant reviews on the use of nanomaterials for preserving stone, wooden, or paper cultural heritage have been conducted [ 38 , 39 ]. In Table 1, nanoparticle-containing materials used in the construction industry are identified, defining their properties and applications in the sector. Table 1. Nanomaterials in construction [34,40,41]. Nanoparticle Type Material/Application Expected Benefits SiO2nanoparticles Concrete Ceramic Windows Reinforcement in mechanical strength, rapid hydration Coolant; light transmission; fire-resistant Flame-proofing; anti-reflection TiO2nanoparticles Cement Windows Solar cell Rapid hydration; increased degree of hydration; self-cleaning Superhydrophilicity; anti-fogging; fouling resistance Non-utility electricity generation Carbon nanotubes Concrete Ceramic NEMS/MEMS Solar cell Mechanical durability, crack prevention Enhanced mechanical and thermal properties Real-time structural health monitoring Effective electron mediation Fe2O3nanoparticles Concrete Increased compressive strength, abrasion-resistant Cu nanoparticles Steel Weldability, corrosion resistance, formability Ag nanoparticles Coating/painting Biocidal activity Clay nanoparticles Bricks and mortars Increased compressive strength and surface roughness Al2O3nanoparticles Asphalt, concrete, timber Increased serviceability ZnO nanoparticles Cement Enhanced performance CaCO3nanoparticles Concrete Accelerated hydration, increased flowability, and increased compressive strength MgO nanoparticles Coating/painting Energy-saving Within the European Union, nanomaterials are regulated under the same stringent framework that applies to all chemicals and mixtures: the REACH and CLP regulations. These regulations require the assessment of the hazardous properties of nanoforms and ensure their safe use [42]. For a substance to be legally manufactured or imported in the EU, all chemicals within the scope of REACH must be registered. Depending on the volume placed on the market, manufacturers and/or importers are required to submit data concerning human health, environmental effects, and hazardous nanoforms, along with a life-cycle exposure estimation [42]. Constr. Mater. 2025,5, 37 16 of 19 3.5. Interpretation of Results This phase involves a comprehensive review of both inventory data and impact scores, forming the basis for drawing conclusions from the study. It encompasses critical elements such as sensitivity analysis and the assessment of uncertainties, ensuring a robust and informed finalization of the LCA. Indeed, as highlighted earlier, LCA studies on nanomaterials inherently confront a significant level of uncertainty. Therefore, it is imperative that all utilized data and sources of uncertainty be meticulously documented. In the current landscape, extracting reliable and robust results from LCA studies on nanoparticles holds substantial value, not only for informing immediate decision-making but also for contributing to the enhancement of existing methods and databases in the broader scientific community [ 47 ]. This commitment to transparency and the acknowledgment of uncertainties contribute to the continuous improvement of methodologies and the advancement of knowledge in the field of nanomaterials. During this final phase of the study, the following recommendations are proposed to ensure a thorough and effective conclusion. Initially, to enhance the rigor and reliability of the study, it is advisable to subject it to an external critical evaluation conducted by a panel of experts with proficiency in both LCA methodologies and nanotechnology. This external review aims to ensure an impartial and thorough examination of the study’s approach, data sources, and findings, leveraging the expertise of individuals who are well versed in the nuances of LCA and nanotechnology [13,47]. Additionally, conducting an uncertainty analysis is essential to gauge the robustness of the results and is recommended as a pivotal step in the study. This analysis provides valuable insights into the reliability of the findings, offering a comprehensive understanding of the potential variations and limitations associated with the data and methodologies employed in the LCA [47]. Furthermore, utilizing the outcomes derived from the LCA studies to augment existing inventory data within databases and contributing to the refinement of impact characterization methods are highly recommended. This proactive approach not only enhances the comprehensiveness of available data but also plays a crucial role in advancing the accuracy and effectiveness of methodologies used for assessing environmental and toxicological impacts associated with nanomaterials [13,47]. If a characterization factor is unavailable for the assessed emissions, it is essential to integrate a custom predictive scenario designed explicitly for the evaluated nanomaterial. This scenario should encompass the following components [47]: • Measurement of the releases of nanoparticles over the entire life cycle of the product, from its inception to its disposal (cradle to grave). • Identification of the specific environmental compartments associated with each instance of nanoparticle release. • Anticipation of the long-term destiny of the released nanoparticles, encompassing an understanding of the transformations that these nanoparticles undergo in the environment following emission. • Evaluation of the toxicity impact on both humans and the environment resulting from the emissions of produced nanoparticles. 4. Conclusions The gap in understanding of the fate and impacts of nanoparticle emissions presents significant challenges for evaluating their environmental and health implications. Current LCA methodologies are limited due to the lack of specific nanoparticle data, which hinders comprehensive risk assessment. To address this, it is essential to adopt alternative methods Constr. Mater. 2025,5, 37 17 of 19 that can evaluate the full range of impacts associated with nanoparticles, focusing on both emissions and their broader environmental and health effects. A crucial step is to ensure explicit reporting of nanoparticle emissions across the entire life cycle of nanoproducts. As current Life Cycle Inventory (LCI) databases lack nanoparticle-specific data, a more detailed and tailored approach to data reporting is necessary to improve LCA’s accuracy. Additionally, integrating predictive modeling and risk assessments into LCA studies can provide a more comprehensive evaluation of potential risks, especially when precise data are unavailable. Efforts like the EU-funded Eunon Nano Data project are already working to fill these gaps by providing accessible information on nanoparticle emissions, environmental fate, and risk assessments [ 49 ]. Such initiatives are crucial for supporting informed decisionmaking in industries utilizing nanomaterials. This study contributes valuable data to the construction industry, focusing on environmental health and safety, and supports the responsible integration of nanoparticles into construction materials. This promotes sustainable practices while mitigating potential risks. However, the variability in manufacturing processes for different nanoparticle types means that their impacts can vary widely. LCA provides a structured approach for decision-makers to balance the benefits and risks of nanomaterials in material selection. To produce reliable LCA results, it is essential to use high-quality data and rigorous methodologies. Understanding comparative Process Contribution Ratings (c-PCRs) within Environmental Product Declarations (EPDs) also aids in identifying opportunities to reduce environmental impacts. The LCA data in these declarations should not only be made publicly available but should also be strategically used to pinpoint areas for improvement. In conclusion, while LCA is promising for assessing the sustainability of nanomaterials, there remains considerable scope for further research. Future studies should analyze the entire life cycle of nano-modified materials, incorporating a range of nanomaterials as modifiers, to rigorously assess their sustainability. Addressing these gaps will be key to ensuring the responsible and sustainable integration of nanomaterials in industries such as construction. Author Contributions: Conceptualization, P.P.-P. and P.M.-M.; methodology, P.P.-P. and B.B.-G.; validation, P.P.-P. and P.M.-M.; formal analysis, P.P.-P., M.A.S.-B. and P.M.-M.; investigation, P.P.-P., M.A.S.-B. and P.M.-M.; resources, P.P.-P., B.B.-G. and E.C.-G.; data curation, P.P.-P. and P.M.-M.; writing—original draft preparation, P.P.-P. and P.M.-M.; writing—review and editing, P.P.-P., M.A.S.-B. and P.M.-M.; visualization, P.P.-P. and E.C-G.; supervision, P.P.-P., M.A.S.-B. and P.M.-M.; project administration, P.M.-M.; funding acquisition, P.M.-M. All authors have read and agreed to the published version of the manuscript. Funding: The results of this article were derived from the project educational platform for life-cycle analysis of treatments based on nanoparticles applied to the construction industry project (code 2022-1-ES01-KA220-HED-000089985), an Erasmus+ project co-funded by the European Union and within the framework of an initiative of 2022 KA220, cooperation partnerships in higher education, with the support of the “Servicio Español para la Internacionalización de la Educación (SEPIE, Spain). The European Commission’s support for the production of this publication does not constitute an endorsement of the contents, which reflect only the views of the authors, and the Commission cannot be held responsible for any use that may be made of the information contained herein. Data Availability Statement: The original contributions presented in this study are included in the article. Further inquiries can be directed to the corresponding author. 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