Chemical reference number (CAS): 542-92-7
What is cyclopentadiene?
Cyclopentadiene is a manmade chemical. Its 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. Its 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?
Breathing: Most people are exposed to cyclopentadiene when they
breathe tobacco smoke or air contaminated by exhaust from automobiles or industries. If a
home water supply is contaminated, people could inhale the chemical when they cook, do
laundry, or bathe.
Drinking/Eating: People may be exposed to cyclopentadiene when they
drink contaminated water. People who handle contaminated soil may be exposed when they eat
or touch their mouths with dirty hands.
Touching: People may be exposed if they handle the chemical,
contaminated soil, or water. If the home water supply is contaminated, people could
contact the chemical when they wash or do laundry.
Do standards exist for regulating cyclopentadiene?
Water: Currently, there is no state or federal drinking water standard
for cyclopentadiene. Until a health-based standard is developed, people should avoid using
water that contains any detectable cyclopentadiene for preparing food. If levels of
cyclopentadiene are very high in your water, you may also need to avoid washing, bathing
or using the water for other purposes. Contact your local public health agency for more
information specific to your situation.
Air: No standards exist for the amount of cyclopentadiene allowed in
the air of homes. We use a formula to convert workplace limits to suggested home limits.
Based on the formula, we recommend levels be no higher than 1.5 parts per million
cyclopentadiene in air. Most people cant smell cyclopentadiene until levels reach
1.9 ppm. If you can smell the chemical, the level is too high to be safe.
The Wisconsin Department of Natural Resources regulates the amount of cyclopentadiene
that can be released by industries.
Will exposure to cyclopentadiene result in harmful health
The following symptoms may occur immediately or shortly after exposure to high levels
of cyclopentadiene in air:
- Irritation of eyes, nose, and throat
- Irritation of skin
- Temporary changes in liver and kidney functions
The following health effects can occur after several years of exposure to
Cancer: Cyclopentadiene has not been tested for its ability to cause
cancer in laboratory animals.
Reproductive Effects: Cyclopentadiene has not been tested for its
ability to cause reproductive effects.
Organ Systems: Cyclopentadiene can damage the liver and kidneys.
Repeated contact with the chemical can also cause allergic skin rashes.
In general, chemicals affect the same organ systems in all people who are
exposed. However, the seriousness of the effects may vary from person to person.
A person's reaction depends on several things, including individual health, heredity,
previous exposure to chemicals including medicines, and personal habits such as smoking or
It is also important to consider the length of exposure to the chemical; the amount of
chemical exposure; and whether the chemical was inhaled, touched, or eaten.
Can a medical test determine exposure to cyclopentadiene?
There are no common laboratory tests for cyclopentadiene in the body. If you develop
symptoms following exposure to cyclopentadiene, or if you suspect that you have been
exposed to high levels of this chemical, doctors can use tests of liver and kidney
function to check for any damage to these organs.
Seek medical advice if you have any symptoms that you think may be related to chemical
(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
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