We are entering a new dimension of the Anthropocene age affecting the Earth and its vital biogeochemical cycles in an unprecedented way. The anthropogenically-produced mass (including plastics, titanium dioxide (TiO2), and ultrafine-soot particles) had surpassed all global living biomass with annual fluxes entering the environment estimated at millions of tons. These anthropogenic particles integrate oceans and interact with the biogeochemical cycles, from microscale to nanoscale (or colloidal scale). The main goal of NANO-GATE is to characterize the presence and the biogeochemical cycling of anthropogenic nanoparticles in the Arctic Ocean. Nanoplastics, TiO2, and nano-soots are targeted due to their extensive use in anthropogenic activities, high reactivity against other contaminants in the environment, and expected ubiquity in the AO. Despite its relatively small size and lower direct contact with human activities, the Arctic Ocean (AO) is one of the most exposed oceans to anthropogenic impacts. While the presence of microscale anthropogenic particles starts to be partially documented there is absolutely no data concerning nanoparticles. And yet, even at (ultra)-trace concentration, and due to their high surface specificity, diffusivity and reactivity, nanoparticles are more likely to interact with biota, especially primary producers, and to impact the main biogeochemical cycles. In light of these properties and the increase in anthropogenic material mass entering the global ocean, there is an urgent need to address the pervasiveness of ANP dispersal, particularly in the AO. NANO-GATE will pioneer ANP research in the AO by providing a unique dataset of their distribution and cycling, with the determination of their behavior with key variables specific to the AO. NANO-GATE will provide unprecedented data to support the various Arctic monitoring program agencies and policymakers and list ANPs as an emerging threat.