(42c) Harmonization of Process and Industrial Safety Principles in the Development of Green Chemicals and Materials: Pioneering the Safe and Sustainable By Design Paradigm

In 2019, the European Commission introduced the EU Green Deal, an ambitious initiative aimed at transforming the European Union into a sustainable and climate-neutral continent. This comprehensive policy framework encompasses a wide array of strategies and measures to address climate change, safeguard the environment, and foster economic growth. The EU Green Deal outlines specific targets, including achieving carbon neutrality by 2050, enhancing energy efficiency, and promoting renewable energy sources. It also places a strong emphasis on conserving biodiversity, promoting sustainable agriculture, and forwarding a circular economy. Within the context of the EU Green Deal and the European Chemicals Strategy for Sustainability (European Commission, 2021), the concept of Safe and Sustainable by Design (SSbD) was introduced.

SSbD encompasses the entire life cycle of chemicals and materials, addressing safety and sustainability considerations from manufacturing to distribution, consumption and disposal. This approach encompasses aspects such as raw materials, safety procedures, recycling, use, and disposal. The application of SSbD principles to chemicals and materials is a significant step toward advancing environmentally friendly industrial procedures, with the European Union (EU) serving as a global benchmark for safety and sustainability objectives. In alignment with these objectives, guidance will be offered for establishing criteria that ensure compliance with these principles as well as fostering innovation to reduce or replace hazardous substances in accordance with emerging regulatory requirements.

As part of the EU Partnership for the Assessment of Risk of Chemicals (PARC) (Marx-Stoelting et al., 2023), a central aim is to establish a concrete and FAIRified (Findable, Accessible, Interoperable, Reusable) platform for assessing the safety of chemicals or materials concerning human health and their environmental sustainability during the development phase. This ambitious objective entails the implementation of data integration techniques and the incorporation of a variety of tools into a standardized methodological framework. These tools encompass a broad spectrum of applications, including Green, Circular, and Sustainable Chemistry, Green Process Design and Engineering, Life Cycle Impact Assessment, Risk and Toxicity Assessment, as well as the alignment with the EU Industrial Strategy, among others.

Process safety, which is frequently neglected during the initial material design phase, represents a comprehensive approach that involves recognizing, evaluating, and addressing hazards throughout a product or process's entire life cycle. A decisive component of process safety is the quantitative risk assessment, aimed at minimizing the chances of unforeseen accidents or failures at industrial settings. This proactive approach not only curtails the need for costly rework but also conserves resources in the long term. Furthermore, it promotes a culture of ongoing enhancement in materials design, emphasizing both industrial safety and environmental sustainability. The PARC SSbD toolbox incorporates a range of functions and hazard estimation tools for precise incident calculations. This includes the assessment of fireball incidents (Martinsen & Marx, 1999), jet and pool fire accidents (Cook et al., 1990), and the estimation of thermal radiation curves following the TNO Yellow Book principles (TNO Yellow Book, 2005). Explosion scenarios are implemented by applying TNO Yellow Book principles (TNO Yellow Book, 2005) as well.

It is evident that the routines described do not provide a comprehensive depiction of potential accidents or the severity of incidents resulting from process failures. To address this limitation, the SSbD toolbox incorporates a process-safety-smart-decision system. During the conceptual design of new ideas or the evaluation of alternative products, this system estimates a safety risk index. This schema relies on chemical structural information, conditional material properties, and calculations from the models mentioned earlier. Strictly speaking, EU PARC SSbD toolbox process safety functionality accepts a limited number of inputs, including flash and boiling point normalized by a reference temperature, flammability, explosiveness (determined using the previously described model outputs normalized with the total mass, lower flammability, and explosive limits, and the NFPA 704 fire diamond principle), as well as process conditions (temperature, pressure, type of inventory), and the rest of the parameters required to run the corresponding models. The data combination process yields normalized and dimensionless factors, which are subsequently added together to compute the corresponding safety index. The higher the index is, the more unsafe the industrial installation. The main objective here is not to provide a final assessment of industrial safety but to enable a comparison basis of numerous alternatives with the initial product for possible substitution or improvement. A more extensive assessment of safety aspects is reserved for a later stage.

A prominent point of discussion revolves around the high number of parameters required to operate the SSbD-smart-decision system, which becomes particularly pertinent for chemicals or materials that are relatively new or/and have not undergone prior evaluations in this context. To tackle this challenge, advanced 3D Quantitative Structure-Activity Relationship (QSAR) methodologies were employed, involving the introduction of artificial intelligence (AI) models for each property of interest. DIPPR's Project 801 Database is incorporated in the property estimation procedure. This approach guarantees that the decision system can apply the relevant methodology even in the absence of data during the development phase. It is noteworthy that the AI models developed thus far have demonstrated R-squared values exceeding 0.8.

Toxicity is assessed with advanced 3D deep learning QSARs, and Probit functions that are parametrized with QSARs as well, if it is needed. Furthermore, concerning the human health safety and the quantitative point of view, a thorough examination of the source to internal dose continuum is facilitated by the incorporation of the INTEGRA platform (Sarigiannis et al., 2014; Sarigiannis et al., 2016) into the SSbD toolbox. This approach employs level three multimedia models, detailed exposure, and occupational exposure models, as well as comprehensive Physiology-based Pharmacokinetic (PBPK) models to evaluate associated risks. Lastly, the assessment of product and process life cycles in the first version of the software is conducted by using the brightway2 framework, a publicly accessible software (Mutel, 2017).

Ensuring the principles of Safe and Sustainable by Design (SSbD) for innovative materials extends beyond only considering chemical structures and their life cycle assessment. It involves a comprehensive examination of the processes, including possible alternative methods, from raw material application to the final product. This approach allows users and industries to gauge the impact of potential accidents and alternative processes. As we design and conceptualize SSbD chemicals and alternatives, we also evaluate the quality and risks associated with the production processes. The presented methodology minimizes the chances of severe accidents, reduces energy consumption, lessens environmental burdens, and enhances production efficiency by optimizing the chemical structures. Our focus is not only on reducing the possibility of leaks through advanced monitoring systems but also on designing green processes to ensure that by-products meet environmental standards and are safe for the human health. This approach also improves working conditions over the long term, enhancing overall well-being. In summary, process safety is not just a regulatory requirement; it is a foundational element for achieving safe and sustainable by design materials. By integrating process safety into materials innovation, we can mitigate risks for the human health, promote environmental sustainability, and encourage innovation.

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