Histamine and other spoilage compounds can form when certain fish species, such as tuna and mahi-mahi, are not chilled promptly after death and maintained in a chilled state, or otherwise treated or processed to prevent microbial activity.  Histamine cannot reliably be removed by washing, freezing, or heating.  As discussed in a recent recall of frozen tuna steak, histamine can produce an allergic reaction called scombroid fish poisoning with symptoms, including a tingling or burning sensation in the mouth, facial swelling, rash, hives and itchy skin, nausea, vomiting or diarrhea, that can appear within minutes to several hours after eating affected fish.

• On December 27, 2021, FDA published notice of the availability of a draft Compliance Policy Guide (CPG), titled “Sec. 540.525 Scombrotoxin (Histamine)-forming Fish and Fishery Products—Decomposition and Histamine (CPG 7108.24),” which would update and replace existing guidance for FDA staff on adulteration associated with decomposition and histamine identified during surveillance sampling and testing of fish and fishery products susceptible to scombrotoxin (histamine) formation.  The draft CPG would revise two guidance levels for the presence of histamine in these fish as follows:

  • If samples have 35 parts per million (ppm) or more histamine (lowered from 50 ppm), FDA may consider the fish to be adulterated because they are decomposed and/or produced under insanitary conditions.

  • If samples have 200 ppm or more histamine (lowered from 500 ppm), FDA may consider the fish to be adulterated based on the presence of a deleterious substance (histamine) which may render them injurious to human health.

The CPG notes that elevated histamine levels can be prevented in fish by adherence to Current Good Manufacturing Practices and Hazard Analysis Critical Control Point (HACCP) principles required by FDA’s Fish and Fishery Products regulation.

• FDA has requested feedback on the draft CPG (docket number FDA-2021-D-0367).  The comment period will be open for 60 days, until February 25, 2022.