For most of us denatured alcohol and meths are much the same. Meths in most places is ethanol with "dont drink me" added. However first it is industrially produced and little or no checking is done on methanol content. Second in some countries it is still a methanol/ethanol blend. Here in New Zealand a lot of meths is imported and its not always obvious where from. Even though it shouldnt contain methanol I wouldnt take the chance that it doesnt, so treat it as methanol.
Even laboratory grade ethanol can have other nasty stuff in it. In my wasted youth (college before turning 21) we would use laboratory alcohol for social events. The professors and TAs were well aware this was going to happen and warned us about impurities that could kill us even in tiny amounts (benzene, for example). The easiest thing for us to do was to analyze the liquid's IR spectrum. So long as there was just the single peak at ethanol's wavelength, and maybe a smaller peak at water's, we knew we had the pure stuff.
