In restaurants. But it’s not necessarily the owners who are at fault — suppliers are selling cheap fish as more expensive varieties.
Some of the findings present public health concerns. Thirteen types of fish, including tilapia and tilefish, were falsely identified as red snapper. Tilefish contains such high mercury levels that the federal Food and Drug Administration advises women who are pregnant or nursing and young children not to eat it.
Ninety-four percent of fish sold as white tuna was not tuna at all but in many cases a fish known as snake mackerel, or escolar, which contains a toxin that can cause severe diarrhea if more than a few ounces of meat are ingested.
“There are a lot of flummoxed people out there who are trying to buy fish carefully and trying to shop their conscience, but they can’t if this kind of fraud is happening,” said Kimberly Warner, a senior scientist at Oceana, who led the study.