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We present a study of reddening and absorption towards the Narrow LineRegions (NLR) in active galactic nuclei (AGN) selected from the RevisedShapley-Ames, 12mu, and Swift/Burst Alert Telescope samples. For the sources inhost galaxies with inclinations of b/a > 0.5, we find that mean ratio of [OIII] 5007A, from ground-based observations, and [O IV] 28.59mu, fromSpitzer/Infrared Spectrograph observations, is a factor of 2 lower in Seyfert2s than Seyfert 1s. The combination of low [O III]/[O IV] and [O III] 4363/5007ratios in Seyfert 2s suggests more extinction of emission from the NLR than inSeyfert 1s. Similar column densities of dusty gas, NH ~ several X 10^21 cm^-2,can account for the suppression of both [O III] 5007A and [O III] 4363A, ascompared to those observed in Seyfert 1s. Also, we find that the X-ray lineOVII 22.1A is weaker in Seyfert 2s, consistent with absorption by the same gasthat reddens the optical emission. Using a Hubble Space Telescope/SpaceTelescope Imaging Spectrograph slitless spectrum of the Seyfert 1 galaxy NGC4151, we estimate that only ~ 30% of the [O III] 5007A comes from within 30 pcof the central source, which is insufficient to account for the low [OIII]/[OIV] ratios in Seyfert 2s. If Seyfert 2 galaxies have similar intrinsic[OIII] spatial profiles, the external dusty gas must extend further out alongthe NLR, perhaps in the form of nuclear dust spirals that have been associatedwith fueling flows towards the AGN.

Multi-wavelength Probes of Obscuration Towards the Narrow Line Region in Seyfert Galaxies