You may have been misled with some of the butane hoopla bro!
Near Zero impurities is a specific manufacturers Madison Avenue designation, not an industrial standard. If you read the small print, it means that there are less than 50ppm impurities in the form of oleaginous waxes (paraffin) in it.
Studies measuring the impurities in their product shows the contamination is actually below 15 ppm, which is what their competitors butane measured too. It actually has to do with how likely the paraffin content is likely to plug the small orifices of expensive butane lighters, because paraffin is non toxic.
Methyl Mercaptan is used in stove fuel to give it an odor, because butane is mostly odorless. They are not required to and don't put it in lighter fuel or R-600 N-Butane refrigerant that they use in food products as a propellant.
Butane is just four carbon molecules in a chain with 10 hydrogen atoms attached. The MSDS lists no LD-50, because it is relatively non toxic.
As far as argon contamination, maybe at some very low level, but argon is widely used for its inert and non toxic properties. If there was very much present, the butane would lose its thermal properties and would be unsuitable for heating.
More likely to find helium in butane, because natural gas is where most industrial helium comes from these days. They in fact remove it from the natural gas to increase the gases heat output per unit volume. Helium is also extremely inert.
I assume I am not whom you perceived to be a know it all, because rest assured I don't know squat overall, but I too have tried the different methods and come to a different conclusion than you have.
I personally like it all, when it is done right, but panel testing the different products most assuredly shows that different people like different things.
Clearly you prefer bubble hash, but it sounds like you have been misled and it is perhaps not for all the right reasons.
