Oceana calls itself “the largest international organization focused solely on ocean conservation.” What it clearly is not: a consumer health group. Otherwise, it wouldn’t be steering people away from fish through alarmism and deception.

Oceana’s “warning signs” have no basis in sound science — only in unfounded fear.

It claims that mercury “find[s] its way into the oceans and the seafood we eat.” But the trace amounts of mercury found in commercial ocean fish are naturally occurring — the result of underwater volcanoes and thermal vents — not the manmade pollution or emissions from coal-fired power plants.

Oceana also falsely declares that there is “mercury contamination in popular fish” and that “tuna is the primary source of mercury in the American diet.” Never mind that all 10 of the most popular fish consumed in America – including canned tuna, salmon, shrimp, crab, and clams — are all low in mercury and far well below the FDA’s very conservative mercury limits. And, levels of mercury in commercial seafood are just as they were nearly 100 years ago.

To amplify its unnecessary warnings, Oceana has “call[ed] on grocery stores to protect their customers by posting warning signs about levels of mercury in seafood.” But scaring consumers will easily dissuade them from eating even the minimum recommended amount of seafood. As the Institute of Medicine cautions, “consumer messages should be tested to see if there are spillover effects for those not targeted by the messages. Evidence suggests that risk-avoidance advice for susceptible groups may be unnecessarily followed by other individuals, or the general public.”

Oceana also dutifully spreads the myth that mercury poisoning in the U.S. is a real phenomenon. The organization’s website cites bunk testimonials that cannot be corroborated by legitimate evidence. After all, no peer-reviewed medical journal has ever recorded a single case of mercury poisoning from the normal consumption of seafood in this country.

So why does Oceana go after seafood?

Andrew Sharpless, Oceana’s chief executive, explained his organization’s approach to Fortune magazine: “People start to care much more and understand the threat to the ocean, when you tell them their tuna fish is contaminated. It’s a dramatic, eye-opening moment for people.”

And it’s profoundly misleading. By just about any measure, fish is one of the healthiest foods on earth.

What deserves a warning sign to the public? Oceana’s fearmongering.