Interference due to oxide formation:

Cation-cation interference

In several cases, mutual interferences of cations have been observed, resulting within reduced signal intensity of the component being determined. Those interferences are neither spectral nor ionic within nature and the mechanism of such interferences is not well understood. Therefore, for example, aluminum interferes along with calcium and magnesium. In addition, sodium and potassium show cation-cation interference on one another.

Interference due to oxide formation

This kind of interference arises because of the creation of stable metal oxide if oxygen is present in the flame, resulting in decresed signal intensity. An alkaline earth metals are subject to this kind of interference. This kind of interference could be eliminated through either using extremely high flame temperature to dissociate the oxides or through using oxygen-deficient environment to generate excited atoms.