High pyrolysis temperature promotes the production of biochar with a strongly developed specific surface area, high porosity, pH as well as content of ash and carbon, but with low values of CEC and content of volatile matter. This is most likely due to significant degree of organic matter decomposition. I know smoke is hazardous but not at that level. But charcol is better than direct burning of coal.
Heating organic matter causes decomposition and the release of volatile organic compounds. Some of these may be toxic and should be capture, and others might be worth recovering. You need a combustion scientist.