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For the first time, the argon abundance relative to hydrogen abundance (Ar/H)in the narrow line region of a sample of Seyfert 2 nuclei has been derived. Inview of this, optical narrow emission line intensities of a sample of 64 localSeyfert 2 nuclei (z < 0.25) taken from Sloan Digital Sky Survey DR7 andmeasured by the MPA/JHU group were considered. We adopted the Te-method forAGNs, which is based on direct determination of the electron temperature,together with a grid of photoionization model results, built with the Cloudycode, to obtain a method for the derivation of the Ar/H abundance. We find thatfor a metallicity range of 0.2 < (Z/Zsolar) < 2.0, Seyfert 2 nuclei presentAr/H abundance ranging from 0.1 to 3 times the argon solar value, adoptinglog(O/H)=-3.31 and log(Ar/H)=-5.60. These range of values correspond to 8.0 <12+log(O/H)< 9.0 and 5.4 < 12+log(Ar/H)< 6.9, respectively. The range of Ar/Hand Ar/O abundance values obtained from our sample are in consonance withestimations from extrapolations of the radial abundance gradients to thecentral parts of the disk for four spiral galaxies. We combined our abundanceresults with estimates obtained from a sample of Hii galaxies, which were takenfrom the literature, and found that the Ar/O abundance ratio decreases slightlyas the O/H abundance increases.

Chemical abundances in Seyfert galaxies -- VIII. Argon abundance estimates