Soot is the black or gray residue left when materials burn incompletely. It contains fine carbon particles along with chemicals, metals, and acids that vary with what burned. Particles small enough to inhale can reach deep into the lungs and pass into the bloodstream.
Exposure can irritate the eyes, throat, and skin and can worsen asthma and heart conditions. Soot is also acidic, so it etches glass, corrodes metal, and stains surfaces the longer it sits. This is why prompt, careful cleanup matters.
If you must be near soot, wear an N95 or better respirator, gloves, and eye protection, and avoid spreading it into clean areas. Thorough soot removal is best left to trained fire restoration professionals with the right equipment. Heartland handles the water, board-up, mold prevention, and debris haul-away side of a fire aftermath, not soot cleanup.