What are the byproducts of burning butane?
The products are generally CO2 gas and H2O vapour + heat and light. Neither gas can be seen but, if you hold a mirror over the flame, it will mist over as the water vapour condenses on its cold surface. In lighting the pipe, you’ll be taking in only water vapour plus some CO2 from the burning butane but, you take that in just breathing the air. However, when the pipe tobacco is smouldering, it’s more than nicotine, even if you have a filter. There’s the other gases of combustion of the tobacco plant too. If you smoke (as I have fro 55 years), you simply take your chances.