acrolein is in cigarettes

An acrolein is in organic chemistry, acrolein or propenal is the simplest unsaturated aldehyde. Acrolein is described as having a piercing, disagreeable, acrid smell similar to that of burning fat. Skin exposure to acrolein causes serious damage. Acrolein concentrations of 2 ppm are immediately dangerous to life. Acrolein may be easily produced by the action of approximately 1 part sodium bisulfate on 3 parts glycerine by weight. Acrolein is such a severe pulmonary irritant and lacrimating agent that it has been used as a chemical weapon during World War I. It is, however, not outlawed by the Chemical Weapons Convention. When glycerol is heated to 280 °C, it decomposes into acrolein. Acrolein tends to polymerize when left at room temperature, leaving a gummy yellowish residue with a putrid odor. Acrolein is also a metabolite of the chemotherapy drug cyclophosphamide, and is associated with hemorrhagic cystitis.

The smell of acrolein is that of burnt fat (when cooking oil is heated to its smoke point).

This is caused by the breaking down of glycerol into acrolein when burning (or overheating, pyrolizing) fat.

The acrolein test tests for the presence of glycerin or fats. There is no general equation for it, although the sample is heated with potassium bisulfate and if acrolein is released, the test is positive.

Because when a fat is heated strongly in the presence of a dehydrating agent such as KHSO4, the glycerol portion of the molecule is dehydrated to form the unsaturated aldehyde, acrolein (CH2=CH-CHO), which has the peculiar odor of burnt grease.

A sample is heated with potassium bisulfate, and acrolein is released if the test is positive.

That's why Acrolein test is a test for the presence of glycerin or fats.

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http://en.wikipedia.org/wiki/Acrolein