I'm not at all sure of his numbers, but the info is basically correct. The soot released by some incense and candles can be pretty toxic. Once Amber (the wife) got cancer the first time, we quit using candles, Nag Champa, and those plug-in air fresheners that warm the perfume. Had read that some of the burned/heated ingredients can create a hazardous soot. (the bathroom still gets the spray, tho)

CND: Toxins in Burning Candles, Candle Wicks, and Incense
EPA Report: Candles & Incense
Holy Smoke: Burning incense, candles pollute air in churches: Science News Online, Aug. 19, 2006

Hennessy:
Been curious about your signature...is it America F**k Yeah, or America F**k You?