Seafood lovers have been warned time and time again about the high concentrations of mercury that is found in fish; a rise in methyl mercury levels in tuna and other large fish have been a public health concern for some time. The Food and Drug Administration recommend that young children and pregnant women limit their intake of tuna and avoid other large species like swordfish.

Yellowfin Tuna

Although many believed that levels of mercury in fish occur naturally, new studies reveal that this might not actually be the case. Believe it or not, humans may actually be to blame for the continuing rise in mercury levels in Pacific yellowfin tuna. Yellowfin tuna is also called Ahi, and can be sold in steak form or in cans, and served raw at sushi restaurants. The very popular fish has experienced levels of mercury creeping up 3.8 percent every year since 1998, and research is linking this constant rise with human activity.

The new study explains that there is evidence suggesting human activity like the burning of coal is causing a buildup of the element in the air and water that is making it into the food chain. “Evidence is piling up that the methyl mercury has an anthropogenic source,” said University of Michigan eco-toxicologist Paul Drevnick, lead author of the study. “It’s coming from mercury emissions that are falling into the ocean.”

“What this number is saying is that the amount of mercury in fish is getting higher and higher all the time, and if it keeps going like that, at some point, most every kind of fish is going to be potentially hazardous,” study coauthor >Carl Lamborg told the Los Angeles Times. “Where that point is, I don’t know.” Mercury levels in the atmosphere have risen by a factor of three over the industrial times, several recent studies have found.

Can it be that humans are inadvertently poisoning our own food supply? Only time will tell if these alarming mercury levels will cause even further oceanic damage.