Here in the States, one can generally obtain MSDS documents - manufacturer's safety data sheets - for any hazardous chemicals.
Concerning denatured alcohol (essentially ethanol deliberately adulterated (poisoned) with dangerous methanol, I remember that we had this discussion in detail a couple of years ago.
"Meths" or methylated spirits as sold in the UK is even more toxic than the denatured alcohol we have here in the States because it has colorants and other crap in it. Our stuff is mostly clear - a combination or relatively safe ethanol with very dangerous methanol.
Pure Ethanol is sufficiently clean-burning that one does not have to be overly concerned about breathing in the products of combustion - mainly water and CO2 and this is why it is OK for indoor fireplaces, cooking stoves and lamps.
It's the liquor industry that does not want to see cheap ethyl alcohol made readily available to the general public, but this stuff really works well and it is almost pure ethanol:
Lumina Products Smartfuel
From the MSDS, we can see that it is >90% Ethanol with the remainder being 4.8% to 9.0% isopropyl alcohol.
I would not recommend using it for Limoncello
MSDS for Lumina Smartfuel
As long as biofuel fireplaces remain legal in California, the fuel should remain available?
Requires additional research, I presume.
Methanol is highly flammable and toxic. Direct ingestion of more than 10mL can cause permanent blindness by destruction of the optic nerve, poisoning of the central nervous system, coma and possibly death. These hazards are also true if methanol vapors are inhaled.
Kleenstrip Denatured Alcohol is 30% to 50% Ethanol and 40% to 60% methanol, so dangerous stuff to be sure.
Ingesting 2 ounces of Methanol is generally fatal to an adult. That would be about 4 ounces of Kleenstrip Denatured Alcohol.
MSDS for Kleenstrip Denatured Alcohol
Edited to fix typos.