“…According to Carter et al, 63 both 2 H and 18 O are vulnerable to enrichment in chitin relative to meat for prawns, and the head can accumulate more metals than the meat. Li et al 41 found that head-on-shellon, headless-shell-on, and peeled-un-deveined shrimp, three shrimp products sold in markets, have different elemental profiles and this was further verified by Davis et al 72 Xu et al 65 reported that δ 13 C, δ 15 N, Na, Mg, Al, K, Mn, Fe, Co, Cu, Zn, As, Se, Rb, Ag and Ba varied significantly among muscle, gills, and hepatopancreas tissues of swimming crabs (Portunus trituberculatus). Thus, separate databases are needed for analysis of different tissue types.…”