Essential and toxic trace elements: Li, B, Na, Na, Mg, Al, Si, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Cd, Sb, Hg, Pb, Ba, Au, V, Ag, Be, Bi, W, Ga, Ge, I, La, La, Sn, Pt, Rb, Sr, P, Zr (40 elements) in hair