Quelques interferences sur le dosage du plomb dans les eaux alimentaires par spectroscopie d'absorption atomique sans flamme

Interferences in the determination of lead in potable water by graphite-furnace atomic absorption spectrometry are examined. The peak-height signal and the pyrolysis/atomization curves are studied as a function of the nature and concentration of the interferent. Some interferences are caused not by the cation or anion, but by the salt. Magnesium chloride interferes most extensively not only by decreasing the signal but also by changing the pyrolysis curve. Interferences are more pronounced in hydrochloric than in nitric acid medium. Frequently, stabilization of an interfering effect from a defined interferent concentration was observed in nitric acid medium whereas in hydrochloric acid medium the signals continued to change.