Heater disaster

Because we were due to have frost the other night, i went out and brought a parasene heater.
got home with it, assembled it and filled it as per instructions.
Once it got dark i lit it, reduced the flame till there was no smoke from it. Went back an hour later to recheck, still no smoke.
Next morning, got up early, opened up tunnel, and couldnt see the other end of the tunnel, just a thick wall of smoke.
I've was feeling very sick at this point, all my plants were looking somewhat wilted, and everywhere was covered in a layer of black soot.
Luckily everything has survived, just a few days of tlc.
My only concern it that i cant seem to be able to shift a slight darkening to the blastic of the tunnel where the smoke was, does anyone know a cure for this.