[AndroidNeox (OP)]

Why is lighting a match so effective at covering the aroma left when one has performed a bowel movement? Is it just covering the odor or is there a chemical reaction actually eliminating some aromatic chemicals?

[Pmb]

Why is lighting a match so effective at covering the aroma left when one has performed a bowel movement? Is it just covering the odor or is there a chemical reaction actually eliminating some aromatic chemicals?

Mythbusters did an experiment on this once. I believe that they determined that the flame burned up one of the components of the gas passed during flatulence while the sulfur covered the smell. One notable thing I recall was that a bic lighter didn't work, only a match worked.

[Bored chemist]

One possible explanation is that sulphur dioxide (from the match) will react with hydrogen sulphide which is one component of the odour of flatus.
2  H2S + SO2 --> 3S +2H2O

The elemental sulphur (the 3S) doesn't smell.

However that reaction is quite slow: I wonder if a big part of the effect is simply covering up.

[AndroidNeox (OP)]

I don't believe the match flame burns up the odiferous gases because only a tiny fraction of the air in the room is exposed to the flame.

Bored, your explanation seems more likely to me.