I just bought 6 new Worthington LP77 tanks. We removed the plug, looked inside, installed the valve and filled them. The air from all the tanks has an odor. Almost like a paint smell. I smelled the source air and there was not any detectable odor. I didn't think to smell inside the tank before the valve was installed. These tanks were supposed to be Nitrox ready so I didn't think they would need to be cleaned before assembly. Any ideas on this?