The atomic absorption spectroscopy of lead

Lead can be determined by atomic absorption spectroscopy at 3 wavelengths. The relative sensitivities are 1:1.5:300. No interferences were found from the cations studied. Anionic interferences were numerous and extensive, but were removed by adding EDTA. The use of a “T” -piece increased the sensitivity of atomic absorption when flame atomizers were used. However, extreme care was necessary in controlling flame conditions both with respect to oxygen-fuel ratio and the type of solvent used. The absorption by combustion products in the flame was high, and in many cases, much greater than that of the lead itself.The most sensitive conditions for the determination of lead appeared to be as follows: wavelength, 2170 A; solvent, aqueous or organic; flame, oxy-hydrogen, with the hydrogen atomizing the sample (reversed from normal). Aflame adapter enabled detection limits of 0.013 p.p.m. to be reached.