Mercury in the Anthropocene Ocean

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. ABSTR ACT. The toxic metal mercury is present only at trace levels in the ocean, but it accumulates in fish at concentrations high enough to pose a threat to human and environmental health. Human activity has dramatically altered the global mercury cycle, resulting in loadings to the ocean that have increased by at least a factor of three from pre-anthropogenic levels. Loadings are likely to continue to increase as a result of higher atmospheric emissions and other factors related to global environmental change. The impact that these loadings will have on the production of methylated mercury (the form that accumulates in fish) is unclear. In this article, we summarize the biogeochemistry of mercury in the ocean and use this information to examine past impacts that human activity has had on the cycling of this toxic metal. We also highlight ways in which the mercury cycle may continue to be affected and its potential impact on mercury in fish.