Moral Courage Mediates the Relationship Between Ethical Climate and Sustainable Environmental Health Literacy Among Nurses

Highlights Public health relevance—How does this work relate to a public health issue? Climate change intensifies health burdens globally, yet healthcare systems contribute substantially to greenhouse gas emissions; nurses, as the largest health workforce, are uniquely positioned to address this dual challenge through sustainable environmental health literacy. Organizational ethical climate shapes nurses’ capacity to access, understand, and apply environmental health information, creating direct implications for climate-responsive care delivery and healthcare system decarbonization. Public health significance—Why is this work of significance to public health? This study provides empirical evidence that moral courage statistically associates as a partial mediator of the relationship between ethical climate and sustainable environmental health literacy among nurses, extending existing mediation frameworks to the environmental health domain. Supportive ethical climates explain 74% of variance in nurses’ environmental health literacy and 66% of variance in moral courage, demonstrating that institutional culture is a powerful, modifiable determinant of climate-responsive nursing practice. Public health implications—What are the key implications or messages for practitioners, policy makers and/or researchers in public health? Healthcare administrators and policymakers should prioritize building ethical organizational climates characterized by psychological safety, participatory decision-making, and explicit sustainability values to equip nurses with both the knowledge and courage needed for sustainable practice. Nursing education and professional codes of conduct must integrate planetary health imperatives and moral courage development alongside clinical training, legitimizing environmental stewardship as a core professional responsibility essential for climate-resilient healthcare transformation. Abstract Despite growing recognition that organizational culture shapes nursing practice, the linking of ethical climate to sustainable environmental health literacy (SEHL) remains poorly understood. This study examined whether moral courage statistically mediates the relationship between perceived ethical climate and self-reported environmental health literacy among Egyptian nurses, rather than observed competencies or clinical actions. A cross-sectional correlational design was employed with 743 nurses recruited from government, private, and university-affiliated hospitals. Participants completed the Hospital Ethical Climate Survey, the Nurses’ Moral Courage Scale, and the Environmental Health Literacy Scale. Mediation analysis used Hayes’ PROCESS macro with 5000 bootstrap samples. Ethical climate demonstrated strong positive associations with moral courage (r = 0.81) and SEHL (r = 0.86), while moral courage and SEHL were also strongly correlated (r = 0.82). Ethical climate explained 74% of variance in SEHL and 66% of variance in moral courage. Moral courage was associated with partial statistical mediation of the ethical climate–SEHL relationship, accounting for 33.4% of the total effect (β = 0.31, 95% CI [0.26, 0.37]), while the direct effect remained substantial (66.6%). These findings suggest that supportive ethical climates may be associated with nurses’ environmental health literacy via two statistical pathways: one directly linked to environmental learning and another indirectly linked to moral courage. Healthcare organizations should prioritize ethical climate development alongside moral courage training as potentially promising approaches to advance climate-responsive nursing practice.