Integrated Environmental Conditions Index (IECI) for Assessing Emerging/Legacy Pollutants and Environmental Integrity

Current environmental pollution and degradation are problems of global concern. Environmental assessment indices are commonly applied for managing and diagnosing the health of ecosystems. However, most indices are specific to a type or group of pollutants or environmental characteristics. Therefore, this study focused on the development of a multi-metric index with the potential to integrate the environmental conditions assessed by specific indices. This index was named the Integrated Environmental Conditions Index (IECI). The IECI was applied to assess the environmental condition of rivers (Escanela, Jalpan, Ayutla, and Santa María) in the Sierra Gorda Biosphere Reserve in Mexico during two periods: the rainy and dry seasons. The study of surface water and sediment in riverbeds was addressed. We characterised ten study sites using both environmental indices and pollution indices associated with toxic metals/metalloids and microplastics. The IECI detected spatio-temporal changes. Seasonal variations in the environmental conditions were evident, as well as a reduction in environmental integrity in upstream sites, mainly due to the presence of microplastics and toxic metals/metalloids. The IECI proved effective in assessing environmental integrity and represents a valuable management tool for integrating environmental data and supporting informed decision-making.