This story was updated at 8:37 p.m. EDT.
Landings of tuna and other large predatory fish species in warm-water oceans account for roughly 70 percent of all methylmercury in seafood, according to new research from the University of Delaware and Harvard University.
Those fish are disproportionately caught by large vessels that have helped drive global markets for marine species and raises new concerns that industrial fisheries may be compromising human health.
In finding published Monday in the Proceedings of the National Academy of Sciences, researchers relied on high-resolution catch data to trace the origins and amounts of methylmercury exposure from seafood sourced from tropical and subtropical oceans where industrial-scale fishing is growing rapidly.
