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The Amazon River is the largest river on earth, accounting for 15–20% of the global fluvial freshwater and discharging a volume of 100,200–240,000 m3 s-1 water into the Atlantic (Espinoza-Villar et al. 2009). The Amazon Estuary is fed by the Amazon River as well as the smaller Pará River to the south (volume discharge: 9,000–38,000 m3 s-1), making it an important source of trace metals and organic matter on a global scale. Although the Amazon basin has been increasingly subject to anthropogenic impacts, however, sparse data existed for trace metals in the Amazon estuary and mixing plume prior to this project (Boyle et al. 1982). Importantly, no data exist to measure the dissolved flux of these dissolved trace metals from the Amazon estuary into the ocean. Trace metals are subject to a variety of removal and input processes in estuaries, including particle adsorption-desorption, colloidal fluctuation, biological uptake, sediment and porewater exchange, and ox (ihydrox) ide formation. Understanding and quantifying these processes is therefore crucial to understanding eventual fluxes of trace metals from the Amazon and Pará Rivers into the Atlantic Ocean. Toward this end, surface samples were collected for dissolved (< 0.2 μm) trace metals (Al, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb and U) on a GEOTRACES process study (GApr11, cruise M147) throughout the Amazon estuary in Apr–May 2018 during a period of high river discharge. Here we present dissolved trace metal fluxes from the Amazon and Pará Rivers based on endmember concentrations and estuarine removal.