Tag Archives: ocean

Where in the World is Mercury? Part 2: Ocean and Fish

By: Noelle Selin

Our previous posts have addressed mercury in the atmosphere, global reservoirs such as oceans and soils, fish and human hair. Since oceans and fish are so important to global mercury exposure, I thought it would be useful to highlight sources of more information about mercury concentrations there. Two recent major studies have been released looking at the mercury problem in aquatic systems. Both of these are being presented at INC-5.

The Biodiversity Research Institute and IPEN, a non-governmental organization involved in the negotiations, have collected worldwide data on so-called “hotspots” of mercury concentrations in fish and human hair samples. The report, available here, found that mercury contamination is ubiquitous in marine and freshwater systems along the world. The report compares fish mercury concentrations from around the world to U.S. EPA human health advisory guidelines. Depending on the country, between 43 to 100% of fish sampled exceeded guidelines; in Japan and Uruguay, concentrations were so high that no consumption was recommended. These guidelines are for one fish mean per month.

From BRI-IPEN report: % of fish samples above health thresholds

Look for Alice Alpert’s interview with Biodiversity Research Institute’s David Evers, who’s here in Geneva, to be posted soon on our blog.

Another key report came out of the Coastal and Marine Mercury Ecosystem Research Collaborative (C-MERC), brought together by the Toxic Metals Superfund Research Program at Dartmouth College. The report analyzed and synthesized the current science on mercury sources  in seafood, and explored ecosystem responses to potential emissions controls.

The report found that mercury pollution is on the rise. In response to emissions controls, methylmercury in open ocean fish would only begin to decrease within several years to decades, while fish in coastal systems could respond over many decades to centuries. In other words, these effects are very long lasting. An interview with Celia Chen, who co-authored the report, was conducted here at INC-5 by Amanda Giang and is posted below.