High-Resolution Trace Element Profiles in Calcium Carbonate Shells using LA-ICP-MS: An Environmental Proxy and Biogeochemical Cycling?

In this study we have used 193 ArF excimer laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), to produce a high resolution (32 mum) shells record of Mn, Zn, Sr, Ba, Mg, Cr, Cu, As, Cd, Co and Pb for the Periglypta reticulate and Tridacna gigas mussel shells from the Yalong bay, Hainan Island of China. Our synthesized CaCO₃ co-precipitation multi-elements discs as the solid matrix- matched standards for calibration, and 42 bCa was selected as the internal standard to compensate the draft of signal. The results also demonstrated our co-precipitation matrix matched calibration method was more appropriate than the commercial NIST610/612 glass standards calibration method. Validation of the matrix- matched LA- ICP-MS technique indicated that the method provides accurate and reproducible (RSD<10%) analysis of trace elements in shells (0.01~3000 mug/g). The detection limits of this method for these elements were obtained in the range of 0.103 to 0.709 mug /g with correlation coefficients (R) better than 0.993. The proposed method was successfully applied to determine the trace elements in the two shells. The high-resolution trace element profiles could be as an environmental proxy and biogeochemical cycling for the area in which the fish or mussel lives.