Chemical reference number (CAS): 542-92-7

Cyclopentadiene is a manmade chemical. It’s either a clear liquid or solid, with a sweet odor like turpentine or camphor. Manufacturers use cyclopentadiene to make resins and other chemicals.

Cyclopentadiene is not commonly found in home-use products. It is found in tobacco smoke and car exhaust. It’s also found in exhaust from coal and oil-fueled fires.

When released into the air, cyclopentadiene breaks down to a less toxic chemical within a few hours.

How are people exposed to cyclopentadiene?

Do standards exist for regulating cyclopentadiene?


Will exposure to cyclopentadiene result in harmful health effects?



Reproductive Effects: 

Organ Systems: 


(P-44595  Revised 12/2010)

This fact sheet summarizes information about this chemical and is not a complete listing of all possible effects. It does not refer to work exposure or emergency situations.

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Last Revised: November 21, 2014