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The contamination status and transport of per- and polyfluoroalkyl substances (PFASs) in the seawater of the Indian Ocean (IO) and an adjacent subregion of the Northwest Pacific Ocean (NWPO) were investigated. Eight legacy PFASs were widely distributed in the surface seawater, and perfluoroheptanoic acid (PFHpA) and perfluorooctanoic acid (PFOA) were the two predominant PFASs. ΣPFAS concentration decreased in the following order: NWPO>Joining area of Asia and Indian-Pacific Oceans (JAIPO)>Northeast Indian Ocean>Southwest Indian Ocean. Hexafluoropropylene oxide-dimer acid, a replacement surfactant for PFOA was extensively detected in the IO (~34.8 pg/L) for the first time, showing an early sign of emerging PFAS spread in global open oceans. Eight depth profiles across the JAIPO (down to 5433 m depth) revealed a "surface-enrichment" and "depth-depletion" pattern for PFASs in the water column, and two noticeable fluctuations were mainly located at depths of 150–200 and 200–500 m. Physical processes, including eddy diffusion, and the origin and trajectory of water mass were crucial factors for structuring PFAS vertical profiles. Mass transport estimates revealed a remarkable PFOA contribution through the JAIPO to IO carried by the Indonesian Throughflow, and a nonnegligible PFHpA contribution from Antarctic Immediate Water to deep water of the JAIPO driven by thermohaline circulation. [Display omitted] This study clarified that legacy and emerging PFASs in the different open areas of the Indian Ocean (IO), contributing to the understanding of the contamination status, transport, and interbasin exchange of PFASs in global open oceans. HFPO-DA was extensively detected in the IO, showing an early sign of emerging PFASs spread in global open oceans. Our results demonstrated the effect of physical processes, including oceanic circulation, eddy diffusion, and origin and trajectory of water mass, on the structuring of large-scale transport and fate of PFASs and found the remarkable contribution of PFASs from the Pacific Ocean to the IO. • The total PFASs concentration decreased in an order of NWPO>JAIPO>NWIO>SWIO. • PFOA and PFHpA contamination in the Indian Ocean are more prominent than PFOS. • HFPO-DA are detected extensively for the first time in the Indian Ocean. • PFASs vertical profiles show a "surface-enrichment and depth-depletion" pattern. • A remarkable PFOA contribution from the JAIPO to the Indian Ocean is demonstrated. [ABSTRACT FROM AUTHOR]

• Increasing trend in vanadium concentrations in aquatic organisms from Asia. • Increases in vanadium concentrations comparable to those from vanadium production. • HC5 for seawater species estimated to be 1.13 (0.05–21.19) μg|L-1. • High and moderate risks to aquatic organisms from seawater concentrations. • Moderate and low health risks from seafood consumption to the 95th percentile group. Vanadium has been classified as a potentially toxic metal and has been given limited attention in comparison to similar trace metals. Similarly, worldwide and continental vanadium pollution and risks remain contested. Here, we synthesized the worldwide concentration of vanadium in marine ecosystems with the relevant ecological and human health risks. We found that vanadium in biota and seawater collected from Asia shows significant increases over the temporal analysis, with rates similar to those reported for vanadium consumption and production. Furthermore, invertebrates have a higher concentration of vanadium than fishes. Similarly, we demonstrate that sediments classified as polluted have concentrations that are not directly correlated with the highest concentrations across continents. Finally, ecological risks were higher from seawater, with potential impacts to 55% of aquatic species in Asia estimated from chronic species sensitivity distribution (SSD). The concentration endangering only 5% of seawater species (HC5) was estimated as 1.13 (0.05–21.19) μg L-1. Estimated daily intakes revealed that overall, there are none to low health risks from aquatic product consumption, yet high risks are plausible to children with consumption patterns in the 95th percentile. [Display omitted] [ABSTRACT FROM AUTHOR]