From Wikipedia under the Escolar page:
Effects of consumption
Like its relative the oilfish (Ruvettus pretiosus), it cannot metabolize the wax esters (Gempylotoxin) naturally found in its diet, which accumulates to give an oil content in the muscle meat of 18�¢ï¿½ï¿½21%. These wax esters may rapidly cause gastrointestin...
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