Determination of Histamine in Freshwater Fish Using ELISA Method: A Food Safety Concern

Histamine fish poisoning (HFP) is a foodborne chemical intoxication caused by consuming a bacterially contaminated fish that are capable of producing histamine. Histamine may cause food intolerance and allergic reaction. Currently, there is no information regarding the level of histamine in fish that are consumed in Bahir Dar, Ethiopia. Hence, the aim of this study is to investigate the occurrence and level of histamine in fish that are commonly consumed in Bahir Dar town, Ethiopia. A total of 52 fish samples are collected from different wholesalers and retailers. The fish include tilapia, barbus and catfish. After sample preparation and acylation, histamine quantification was performed using Enzyme-Linked Immunosorbent Assay (ELISA) following the protocol provided together with the kits (RIDASCREEN ® HISTAMIN, Art. No. R1604). Histamine was detected in all fish samples in concentration ranging from 1.3 to 290 mg/100g. Approximately, 21% of the samples exceed the tolerance limit of histamine contents (50 mg/100g) accepted by European countries. Relatively, the mean histamine level was higher in tilapia, followed by catfish and barbus at a level of 40, 34 and 30 mg/100g, respectively. The maximum level was detected in tilapia at a level of 290 mg/100g and minimum level (1.3 mg/100g) was found in catfish. The mean histamine level in all analyzed fish was below the tolerance limit of histamine contents established by EU regulation. Further studies are needed to delineate the level of other chemical contaminants such as mercury and arsenic.