Fish: Escolar and Oilfish

Abstract

A small number of fish species have very high levels of indigestible wax esters in their flesh. These wax esters can accumulate in the rectum and lead to an unpleasant oily diarrhea that has been termed keriorrhea. Two species of fish in particular have been implicated in this illness-. Lepidocybium flavobrunneum and Ruvettus pretiosus-otherwise known as escolar and oilfish, respectively. Both of these species belong to the Gempylidae and so the wax esters have been termed "gempylotoxin." Symptoms tend to develop within a few hours of consumption and may last for a few days. Different jurisdictions take different approaches to both of these fish, with some-such as Japan and Italy-currently banning their sale, while others do not. Where the sale of gempylid fish is not banned, public health authorities often recommend that consumers be warned of the potential side effects of gempylotoxin, and to limit intake.