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Opah (also known as Moonfish)

Opah, also known as moonfish, is a tropical species that is caught in Hawaiian waters. It is very high in mercury levels, and adults are not recommended to eat more than one serving of opah per month. Additionally, opah may be contaminated with a tropical marine toxin that causes ciguatera, a serious foodborne illness that improves with time but has no cure. Ciguatera is found in tropical reef fish, and cannot be cooked out of food. Be sure to ask at restaurants whether your tropical fish has been tested for the presence of this toxin. If you choose to eat tropical reef fish, consuming small portions and selecting smaller-sized fish may help you avoid the more serious side effects of this toxin.

Little is known about this wandering fish, and no assessment of the size of its population has been conducted. It has been caught increasingly in the past decade, perhaps due to increased fishing pressure on tunas in the region since they are often found together. Opah is not usually targeted by any major commercial fishery, but rather is caught incidentally in the longline fishery for tunas and swordfish. Its biology and life history are also not well understood.

Recommended alternatives to opah (also known as moonfish):
Atlantic mackerel
Barramundi, U.S. farmed
Black cod, Pacific U.S. (also known as sablefish)
Cod, Pacific (not trawl-caught)
Salmon, U.S. wild-caught Alaska
Snapper, Mangrove or Gray
Tuna, Atlantic skipjack
Tuna, Pacific Albacore

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Mercury and PCB contaminant information for the Smart Seafood Guide is drawn from Environmental Defense Fund’s Health Alert List. Environmental Defense calculates health advisories based on government databases and scientific studies. Read more.

* Disclaimer

These recommendations are intended as a general reference. They are not intended to provide specific medical advice, supplant any government warnings or otherwise prevent exposure to any health hazards associated with seafood. People should always follow proper acquisition, handling and cooking procedures of any seafood they prepare or consume.