From Local Pollution to Planetary Boundaries: Reframing Environmental Contamination through Multi-Scale Systems Reviews

Environmental contamination has long been addressed primarily at local scales, focusing on site-specific pollution events and their immediate ecological and human health impacts. However, the escalating complexity of global environmental challenges necessitates a reframing of contamination through multi-scale systems perspectives, extending from local sources to planetary boundaries. This narrative review synthesizes recent literature to explore how local pollutants aggregate and interact across scales, ultimately influencing Earth's system limits as defined by the planetary boundaries framework. We examine the conceptual evolution of planetary boundaries, highlighting updates that underscore the transgression of multiple thresholds due to anthropogenic activities. Key themes include local-scale contamination sources such as industrial emissions and agricultural runoff, their escalation to regional transboundary issues, and their culmination in global phenomena like climate change and biodiversity loss. Employing systems thinking, we review integrative approaches that model multi-scale dynamics, including nutrient pollution in river systems and volatile organic compounds apportionment. Case studies on persistent contaminants like microplastics and per- and polyfluoroalkyl substances (PFAS) illustrate how local actions reverberate globally, often amplifying Earth system interactions. Challenges in data integration, modeling uncertainties, and policy alignment are discussed, emphasizing the need for holistic frameworks to achieve sustainability within safe operating spaces. By reframing contamination through multi-scale lenses, this review advocates for interdisciplinary strategies that bridge local remediation with global governance, fostering resilient environmental management in the Anthropocene. Ultimately, the objectives are to highlight gaps in current understanding and propose pathways for future research that integrate systems reviews to prevent further planetary boundary transgressions.