Background <p>Marginalized urban neighborhoods (MUNs) in Mexico are shaped by persistent structural inequality, precarious labor, and environmental degradation, particularly in communities engaged in artisanal brickmaking. These conditions generate multimodal risk, arising from the interaction of environmental exposure, social vulnerability, adverse health conditions, and limited institutional response capacity, often resulting in localized but largely unrecognized humanitarian crises.</p> Objective <p>This study presents the Humanitarian Scenarios Index (HSI) as a multidimensional diagnostic tool designed to assess humanitarian health risk and support preventive public health and environmental interventions in vulnerable urban settings.</p> Methods <p>A community-based cross-sectional screening was conducted. The HSI comprises 21 indicators organized into three components: threat, vulnerability, and response capacity. Using a mixed-methods approach, the index was applied at the community level in three artisanal brickmaking neighborhoods in the Bajío region of Mexico: Las Terceras (San Luis Potosí), San Nicolás (Querétaro), and Yerbabuena (Guanajuato).</p> Results <p>Results revealed high to very high humanitarian risk across all sites, driven primarily by environmental exposures, poverty, food insecurity, and limited access to health services and information. Beyond its diagnostic function, the HSI supported an exploratory spatial and social characterization of risk and participatory, community-based diagnostic processes aimed at reducing vulnerability.</p> Conclusion <p>These findings suggest that the HSI represents a context-sensitive exploratory application for the assessment of chronic humanitarian risk in environmentally and socially vulnerable populations.</p>