Scombrotoxin Quantification

Scombrotoxin or histamine, is a foodborne toxin most associated with the consumption of certain fish species.

Figure 1. Examples of foods associated with food toxin scombrotoxin

Fish that particularly have more risks associated with scombrotoxin are scombridae family fish such as mackerels and tunas and a few other fish species such as bluefish and mahi-mahi. Scombrotoxin is a histamine generated during the storage of fish. It is usually produced by the action of spoilage bacteria after the substances in the muscle protein of the fish was degraded by bacteria. Bacteria that can form histamine have the ability to grow and produce the toxin in a wide temperature range. This is a natural spoilage process and may result in the production of scombrotoxin with toxic effect.

Scombrotoxin cannot be destroyed through the process of freezing, smoking, canning or cooking. So scombrotoxin is not limited to fresh or frozen fish. The toxin may be also found in cured and canned fish products. The mishandling of the fish containing scombrotoxin in home settings can contribute to the incidence. The food service also should be better advised in the handling and selection of fish products.

The consumption of a certain species of marine fish that have partial bacteria spoilage can cause food poisoning. The scombrotoxin in some marine fish can cause a type of food intoxication - scombroid poisoning. Symptoms of scombrotoxin poisoning include red rash, nausea, vomiting, and diarrhea. The health impacts of scombroid poisoning is usually not severe. All symptoms caused by scombrotoxin typically can resolve within a short period of time. Scombroid poisoning is among the top four that are most reported seafoodborne illnesses.

Regulatory agencies have provided recommendations on the proper monitoring and handling of the related fish species such as rapid chilling, supplier control, and good hygiene practices for the effective control of the scombrotoxin concerns. In most cases, the level of histamine in fish that have caused illness are above 200 ppm. There are currently no established regulatory guidelines for all the various types of fish of concern. Based on the U.S. FDA's standard, the poisonous action level for tuna was set as 50 mg histamine per 100 g of edible fish.

The procedure for the analysis of scombrotoxin or histamine in foods includes sample preparation and extraction, and detection/quantification. We control sample preparation factors and we have expertise in the sample preparation of a variety types of food matrices. The sample preparation has significant effect on the accuracy of the level measured in the food samples.

We offer accurate and validated analytical methods that have been widely applied in the determination of scombrotoxin in food samples to meet customers' needs.

Immunoassay (enzyme linked immune sorbent assay, ELISA)

ELISA is an AOAC approved method for the quantitative analysis of scombrotoxin in scombroid species of fish. The range of quantitation of this method was from 2.5 mg/kg to 50 mg/kg.

We also maintain high quality assurance for the analysis. The recovery of internal standard, the use of blanks and spikes is monitored for each batch of analysis.