A new study published in *Communications Earth & Environment* reveals alarming changes in Arctic rivers, which are turning toxic orange due to iron particles released from thawing permafrost. As climate change accelerates, previously frozen soils are melting, leading to two main processes causing the discoloration. At higher elevations, pyrite, or fool's gold, breaks down into iron and sulfuric acid, leading to acid rock drainage. In contrast, lower elevations see wetlands expanding, where microbes convert iron into soluble forms that rust upon contact with oxygen. The ecological consequences are severe, as fine iron particles can remain suspended in water, disrupting food webs and harming species like salmon. The study also indicates a time lag in contamination, allowing scientists to predict future water quality based on ground temperature data. This phenomenon is not isolated to Alaska; similar conditions exist globally, raising concerns about the widespread impact of climate change on pristine ecosystems. Researchers stress the importance of identifying and protecting critical habitats as these changes become more prevalent.