Aldehyde, formula CH3CHO, formed in the oxidation of ethane and other organic compounds It is a major precursor to the pollutant, peroxyacetyl nitrate (PAN)
An organic compound (chemical formula C2H2O) produced by yeast during fermentation Acetaldehyde is actually an intermediate step in the production of ethanol, and is normally not present in significant quantities in the finished beer Acetaldehyde has a "green apple" aroma and flavor
an aldehyde found in cigarette smoke, auto exhaust, smog, and created in the liver from alcohol Acetaldehyde autoxidizes (spontaneously oxidizes in the presence of air) to produce the organic peroxidase perecetic acid and damaging free radicals, and is a mutagen, carcinogen, and cross linker