Fractionation and Spatial Distribution Analysis of Trace Elements in Wild and Farmed Shrimp from Northeast Brazil

Shrimp is an important commodity, and its production has been increased through aquaculture systems. This animal can bioaccumulate trace elements in their tissues, including toxic ones. The entire body of the animal can be used in culinary processes in food preparations. Thus, the distribution of trace elements in shrimps is a concern. The whole and fractionated (muscle tissue, carapace and viscera) samples of wild and farmed shrimps (Farfantepenaeus brasiliensis and Litopenaeus vannamei, respectively) from northeast of Brazil were analyzed. As, Cd, Co, Cu, Cr, Mn, Mo, Se and V were quantified by ICP-MS while for Al, Fe and Zn, MIP-OES was employed. Spatial distribution of the muscle tissue fraction cross-section of the shrimps was performed by LA-ICP-MS to assess the distribution of As, Cu, Fe, P, S and Se in both shrimp species. Wild and farmed shrimps show different content for almost all analytes, except Co and Mn. The levels of Cu, Mo, and Zn were higher in farmed shrimp. The vanadium content in wild shrimp was around one order of magnitude higher than that found in farmed shrimp. For Brazilian legislation, As (11.5 mg kg-1) and Cd (1.94 mg kg-1) in wild sample exceed around 10 times and 4 times, respectively, the limit established by Brazilian legislation. The trace elements distribution in fractions of shrimps are similar for both species, the majority of these elements are mainly found in carapace. Cd and Mn are almost completely present in the carapace. The most part of As, Se and Zn is in muscle tissue for both shrimp species, except As in farmed shrimp that is mostly in carapace. Similar spatial distribution was found for As, Se, P and S, probably due to the chemical similarity among them. Relevant information is obtained only through LA-ICP-MS analysis, which showed the correlation between the elements through their spatial distribution.