The Investigation And Evaluation Of Harmful Element Contents And Formaldehyde Level In Dry Seafood In Jinan Supermarkets And Farmer’s Markets

ObjectivesWith the development of the society, the diversification of food supplies the convenience to people, but the security risks. Sea food are more and more loved by people for their high nutritional value, strengthening the immune system, disease prevention and anti-aging. As a result of the increasing ocean pollution, the contents of heavy metals in sea food seriously increased. During the process from live to dry sea food, the harmful elements will still remained in the product. Meanwhile the formaldehyde was frequently added to the products to prolong the period of validity and increase the flavor, which has been drawn a wide attention in the world. In this study, dry sea foods of different kinds were randomly collected from the supermarkets and famer’s markets in Jinan City. The content of formaldehyde was measured by high performance liquid chromatography and the contents of Pb、 Cd、 As were measured by atomic absorption spectrophotometer and atomic fluorescence spectrophotometer after microwave digestion.Methods1Sample collection and pretreatmentDifferent kinds of dried sea food including shrimps, small shrimps, cephalopoda and fish were collected from supermarkets and farmers’markets randomly after early investigations to determine the sampling places.2Determination After pretreatments, concentrations of Pb, Cd in the samples were determined by graphite furnace atomic absorption spectrophotometer. As is determined by atomic fluorescence spectrophotometer. Formaldehyde is determined by high performance liquid chromatography.Results1The contents of harmful elements in dry seafoodAmong the products analyzed the Cd and Pb contents in dried small shrimps were the lowest (P<0.05), according to the sequence:cephalopoda> fish> shrimps> small shrimps. And the values were all lower than national standards. Similarly, the As values in the four kids of dried seafood were also lower than the national standards but with the sequence:fish> shrimps> small shrimps> cephalopoda. When compared between the products from supermarkets and farmer’s markets, and between different cities, only As content was significantly different, higher in the products from supermarkets and lower in those from Yantai territorial waters.2The contents of formaldehyde in dry seafoodThe formaldehyde contents sequence was small shrimps> fish> shrimps> cephalopoda.Compare to brand Hai Zhihui, the formaldehyde contents in brand Haiqi were lower (P<0.05).3The harmful heavy metals pollution index in dry seafoodThe harmful heavy metals concentrations of all kinds in dry seafood were all lower than those in the national standard, meaning that when using Pi and P综, all kinds of dry seafood were not affected by Pb, Cd, and As.Conclusions1According to the pollution index evaluation, the dry seafood products were not significantly polluted by Pb,Cd and As.2The formaldehyde contents of all samples were all below the limits value of national standard. Among the products collected formaldehyde contents in cephalopoda was the highest.3The contents of harmful metals in the products from Yantai, Qingdao, Rizhao demonstrated little difference.