In the flesh of skipjack tuna, the trace of human pollution
An international team, in which MIO participates, describes for the first time the mechanisms that lead to mercury contamination of Pacific tuna. It shows the important role of bio-geochemical processes in the oceans and points to atmospheric emissions in Asia
Power plants, steel mills, cement factories... all coal combustion releases metallic mercury into the atmosphere. The same is true for gold panning, an often clandestine activity that uses mercury to coagulate gold straws, releasing metal into waterways and the atmosphere. The oceans are the main receptacle of this mercury of anthropic origin.
Added to this is the mercury released by volcanic eruptions and underwater hydrothermal springs. In total, the oceans would contain about 300,000 to 400,000 tons of mercury, including about 80,000 tons related to human activities, a large global study concluded in 2014 New work, published January 11 in PNAS, clarifies the mechanisms of contamination of fish in the Pacific.