Toward robust decision-making in safe and sustainable by design (SSbD): current state and recommendations for MCDA integration

Designing and evaluating alternative chemicals, materials, processes, or products using a Safe and Sustainable by Design (SSbD) approach can be facilitated by integrating decision support methods like multicriteria decision analysis (MCDA) to evaluate safety, environmental, economic, and social sustainability criteria. Clear guidance is needed to assess chemical, material, or product life cycles on various criteria, especially when a wide range of options is available, and multiple stakeholders’ interests must be accounted for. This study adds to guidance on the implementation of MCDA in SSbD assessments. Reviewing a set of 18 papers addressing MCDA and safety and sustainability assessments, we discuss various decision-making features (MCDA process characteristics) that require development for the application of MCDA in the SSbD framework. We identify six features for further exploration, including defining the decision-maker and problem statement, justifying the set of alternatives under evaluation, defining whether the system should allow for rank reversal, taking a life cycle perspective and defining the assessment scope, justifying the set of criteria used for the assessment, and managing uncertainties. These issues motivate the call for guidance on defining SSbD-specific issues that influence the selection of a suitable MCDA method for a specific problem, to ensure tailored decision-making recommendations. Addressing the identified features should help clear the path toward methodologically sound studies, useful results, and appropriate decision support. • The novel SSbD concept can be facilitated by MCDA methods. • Guidance on implementing MCDA for complex decision-making in SSbD is needed. • Six decision-making features toward sound decision support need further attention. • Addressing these features will pave the way toward methodologically sound studies.