Program: GN-2010B-Q-68

We propose mid resolution multi-object optical spectroscopy with GMOS/Gemini of a sample of blue supergiants in the inner region of M33. We will obtain precise stellar parameters and chemical abundances, that will provide new constraints on the chemical abundance gradient in the central parts of M33, where the data from Rosolowsky & Simon (2008) indicate that HII regions lying at the same distance from the galactic center can differ by up to 0.8 dex in the O/H. They will also allow us to derive stellar metallicities very close to the most discrepant HII regions of the Rolowsky & Simon sample, and further investigate the apparent inconsistency between HII region and stellar abundances presented by U et al. (2009).