We are presently developing a method for simultaneously evaluating the absolute concentrations of the complete relevant inorganic spectrum from Lithium-7 to Uranium-92 using laser ablation ICP-MS.  The method should permit ca. 70 or more elements at ppm and ppb (maybe ppt for some elements) levels of sensitivity, in seconds, and at spatial resolutions well below the diameter of the hair along it's length.

Congrats ! My special concern is about sampling. Concentrations are different on 16 different spots in scalp, we used occipital hair. On the other hand what about eliminating exogen concentrations by washing (washing method). Finally individual values are not a tool for clinical laboratory. Only group standard values we found have a possible useful value.   

No doubt a full research endeavor is required.  I should also have mentioned that the method has already successfully reached the point at which we can evaluate 71 elements (90 second sampling) of whole blood, urine, and saliva (1 mL minumum).  Comparisons of hair with biofluids should permit better interpretations of the stoichiometry of elements in the body.