They found that mercury concentrations in yellowfin tuna increased about 5.5 percent per year between 1998 and 2008.
Levels in bigeye tuna increased about 3.9 percent per year from 2002 to 2008. Mercury concentrations tended to be greater in bigeye tuna than in yellowfin tuna.
The work was reported in a study scheduled for online publication March 6 in the journal Environmental Toxicology and Chemistry.
