Methylmercury contamination increasing

WASHINGTON, May 6 (UPI) -- U.S. Geological Survey scientists say they've determined Pacific methylmercury contamination will increase 50 percent by 2050 if current rates continue.

The researchers documented how mercury emissions from human sources make their way into the North Pacific Ocean, including the long-range transport of mercury within the ocean originating in the western Pacific Ocean.

Methylmercury -- a highly toxic form of mercury -- can cause serious health concerns for those eating seafood, the scientists said.

"Mercury researchers typically look skyward to find a mercury source from the atmosphere due to emissions from land-based combustion facilities," study co-author David Krabbenhoft said. "In this study, however, the pathway of the mercury was a little different. Instead, it appears the recent mercury enrichment of the sampled Pacific Ocean waters is caused by emissions originating from fallout near the Asian coasts. The mercury-enriched waters then enter a long-range eastward transport by large ocean circulation currents."

The study is reported in the journal Global Biogeochemical Cycles.