**2.1 Sample collection**

Six different brands of canned fish products manufactured in three different Asian countries were purchased from open markets, wholesales shops and super markets (chain-stores) in Nigeria. Their storage media were tomato sauce, soyabean oil and curry sauce and the species canned were mackerel, sardine and skipjack tuna with an average weight of between 106 and 155 g/Can respectively. The expiration date of samples was between two to four years as at the time of study and bought samples were taken to the laboratory, kept in clean dry/cool place prior to digestion and analysis.
