Environmental health literacy: an exploratory conceptual redefinition and explanation structuralized from comprehensive multidisciplinary expert perspectives along with public insights

• Provides a novel definition of EHL, independent of pre-existing frameworks. • Encompasses a broad range of environmental domains, surpassing prior studies. • Integrates multidisciplinary academic and executive expertise with public insights. • Lays the foundation for EHL assessment tools and educational interventions. • EHL framework guides policy and planning for resilience and sustainable development. The environment plays a critical role in public health and sustainable community development. Enhancing Environmental Health Literacy (EHL) is essential for mitigating health risks, improving quality of life, and promoting environmental protection. However, as a relatively new concept, EHL remains conceptually ambiguous and requires further clarification. This study aimed to explore and redefine EHL while identifying its core dimensions. Using an exploratory qualitative approach, we conducted in-depth, semi-structured interviews with 35 experts in public health and environmental sciences, as well as 30 diverse adults from Tehran, capital of Iran. Participants were selected through purposive and snowball sampling between February and October 2024. Data were analyzed using conventional content analysis guided by Graneheim and Lundman’s approach. Analysis resulted in 620 initial codes that were organized into 18 subcategories and six main dimensions of EHL: cognitive, affective, behavioral, media, basic, and communication literacy. Additionally, two overarching conceptual approaches emerged—environment-oriented and content-oriented—reflecting differences in how participants viewed the environments relevant to EHL and the disciplinary domains that inform its content. By integrating multidisciplinary expert insights with lived perspectives from adults, this study provides a comprehensive, contextually grounded conceptualization of EHL. The findings provide a foundation for developing assessment tools, designing targeted educational programs, and formulating policies to enhance EHL across diverse settings. By equipping individuals and communities with EHL to navigate environmental risks, this research underscores its role in shaping effective public health interventions, promoting environmental sustainability, and enhancing resilience in both urban and non-urban contexts.