Eating yellowfin tuna (ahi) can mean ingesting mercury, the levels of which have been increasing in the species, according to scientists.

An analysis of mercury in tuna over the past half century revealed the heavy metal’s levels have increased 3.8% annually, according to researchers Paul Drevnick, Carl Lamborg and Marty Horgan, who published their findings in the journal Environmental Toxicology and Chemistry. The data reflects the increasing level of mercury in ocean fish, reaching the level—0.3 parts per million—the Environmental Protection Agency (EPA) considers unsafe for human consumption because of the neurotoxin’s effect on the brain and nervous system.

Children can be born with elevated amounts of mercury in their blood, which can result in a “significant” I.Q. deficit, according to the report.

Mercury pollutes the oceans after being emitted as a gas from sources such as coal-burning power plants, Drevnick wrote at The Conversation. It can travel around the world in the atmosphere before settling in the ocean and winding up in tuna. As more mercury is released into the atmosphere, it accumulates in large ocean fish at an even greater rate.

“The ultimate solution to the problem is to control mercury emissions to the atmosphere at their source,” he wrote.

-Noel Brinkerhoff

To Learn More:

The Mercury Level in Your Tuna Is Getting Higher (by Paul Drevnick, The Conversation)

Increase in Mercury in Pacific Yellowfin Tuna (by Paul E. Drevnick, Carl H. Lamborg and Martin J. Horgan, Environmental Toxicology)

One-Third of Fish Sold as Food are Mislabeled…and Watch out for Sushi Bars (by David Wallechinsky and Noel Brinkerhoff, AllGov)

State Warns Women and Kids to Skip Mercury-Tainted Fish in California Lakes (by Ken Broder, AllGov California)

14% of Mercury in Great Lakes Comes from China…but the Largest Source is Nearby Coal-Fired Power Plants (by Noel Brinkerhoff and David Wallechinsky, AllGov)