Groundbreaking study uses seabirds as indicators of mercury presence through the North-Atlantic Arctic. Results of grave importance for Arctic communities as concentrations increase from the Barents Sea to the East coast of Canada.
Map showing mercury concentrations with highest values in dark blue and lowest in yellow. Figure: NINA
Mercury (Hg) is a toxic substance that accumulates in the food chain and causes detrimental effects on wildlife and human health. The spatial distribution of this toxicant, however, is not well known, especially in food webs and at larger scales in the marine environment.
Seabirds as indicators
In a groundbreaking study recently published, a group of researchers use seabirds to assess the spatial distribution of mercury in the North Atlantic food web. The high resolution, and population and geographic magnitude of the study is unprecedented, says NINA researcher and head author, Céline Albert.
Tracking data from 837 seabirds from seven different species and 27 breeding colonies combined with feather analyses revealed the presence of mercury through the North Atlantic Arctic.
Mercury increasing from east to west
The maps show an east-west gradient in mercury concentrations, increasing from the Barents Sea in the east to the East coast of Canada in the west. Along the mercury concentration gradient, we see hot spots around southern Greenland and the East coast of Canada and a cold spot in the Barents and Kara Seas, says Albert.
The study indicates that the observed gradients could be influenced by ocean currents and melting of the Greenland Ice Sheet.
Of great importance for Arctic communities
This study is considered of great importance for Arctic communities who rely on the marine environment for their livelihoods.
Indeed, Arctic Indigenous Peoples, and especially the Greenlandic and Canadian Inuit communities, possess some of the highest concentrations of mercury in the world, with several documented negative health effects.
With this background, the group of researchers behind this study urge the international community, including under the Minamata Convention on Mercury, to take new and rapid action to address mercury contamination of the environment and the subsequent risk to human health.
Our work demonstrates how wildlife can be used as cost-efficient bioindicators to gather important information on mercury distribution at a large scale, essential to enable decision-makers to take necessary action, concludes Albert.
Minamata Convention on Mercury
The Minamata Convention on Mercury came into force in 2017, and is the only UN Convention dealing with only one chemical substance.
The Convention is a global treaty to protect human health and the environment from the adverse effects of mercury
Norway implements its obligations under the Convention through the EU Regulation on mercury (EU 2017/852) which bans the import into the EU and the export from the EU of mercury, mercury compounds, mixtures of mercury and mercury added products.
Read the article published in PNAS here
Contact:
Céline Albert
Børge Moe