In the annals of consumer products, Febreze, the famous product made by Proctor & Gamble that created the air freshening market currently valued at $20 billion per year, is something of a legend.

As the story goes, a lowly P&G chemist who was a heavy smoker was messing around in his laboratory, experimenting with a starch-based chemical called betacyclodextrin, or HPBCD. Cyclodextrins are cyclic oligosaccharides—a grouping of large sugar molecules that form a ring-shaped molecule that is hydrophilic S (absorbs or dissolves in water) on the surface with a hydrophilic central cavity that is insoluble in water.

The unique donut-shaped molecule's outer surface partially dissolves the molecules of whatever odor it comes in contact with, then encapsulates them in the center, essentially trapping the odor molecules so they can no longer be recognized by the olfactory receptors in the human nose.

Air fresheners and other products containing beta-cydodextrin, or HPBCD, have caused a raft of serious allergies. Cate Montana investigates

When the chemist came home from work one day, his wife asked him