no its not
You didn't answer the question. Why not?
The product of clean combustion of propane is carbon dioxide and water vapour. Same for natural gas(methane).
As long as the appliance is getting enough oxygen, there is not a risk of carbon monoxide being produced from the combustion. Hence, you do need to ensure there's enough ventilation (opening a window, per what watersprite suggested).
If it were not safe, how do propose that people safely use the propane stoves in their RVs?
Or a natural gas stove in their home, for that matter?