Friday

Active Galactic Nuclei (AGNs) present in their spectra strong metal and hydrogen emission lines, whose relative intensities can be used to derive the abundances of heavy elements in the gas phase of these objects. This feature, associated
with their high luminosity, makes they essential to the study of chemical evolution
of galaxies along the Hubble time. In opposite to star-forming regions, abundance determinations in AGNs have been obtained mainly for the oxygen, being the
abundance of other metals poorly or unknown in these objects. In view of that, we compile from the literature narrow optical emission line intensities of a large sample of local (z 8.7], which can not be explained by the oxygen depletion onto dust grains.  These results indicate a primary and secondary stellar nucleosynthesis production for Ar and Ne, respectively, for the high metallicity regime. Also, they produce
important constraints to studies on neon stellar nucleosynthesis.