Trace element profiling of dental tissues using laser ablation inductively coupled plasma mass spectrometry

Laser ablation-inductively coupled plasma-mass spectrometry has been used to generate elemental fingerprints of individual teeth, which have been sectioned to provide a sample which represents the time axis of tooth development. The ablated area is of the order of 100 mu m across, and the ablation process is reproducible, measured using phosphorus. Studies on modem teeth reveal that the mercury and gold concentrations decrease from the outer (mouth exposed) parr of the tooth to the inner newly deposited material. In contrast, the lead content increases from the outer part to the inner reflecting the exogenous origin of the mercury and gold, and the endogenous origin of the lead from the blood supply. Studies on a 19th century tooth from Spitzbergen reveal the presence of a range of lanthanide elements which occur naturally in the area. Studies of the concentrations of other elements present in teeth permit the comparison of data between teeth via the use of element/element ratios. The calcium/phosphorus ratio is recommended for this purpose.