Chlorinated Dibenzo-p-dioxins (CDDs)

CAS ID#: 

Affected Organ Systems: Cancer, Dermal (Skin), Developmental (effects during periods when organs are developing), Endocrine (Glands and Hormones), Immunological (Immune System), Neurological (Nervous System), Reproductive (Producing Children)

Cancer Classification:  Please contact NTP, IARC, or EPA with questions on cancer and cancer classification.

Chemical Classification: Dioxins, Furans, PCBs (contain phenyl rings of carbon atoms)

Summary: CDDs are a family of 75 chemically related compounds commonly known as chlorinated dioxins. One of these compounds is called 2,3,7,8-TCDD. It is one of the most toxic of the CDDs and is the one most studied. In the pure form, CDDs are crystals or colorless solids. CDDs enter the environment as mixtures containing a number of individual components. 2,3,7,8-TCDD is odorless and the odors of the other CDDs are not known. CDDs are not intentionally manufactured by industry except for research purposes. They (mainly 2,3,7,8-TCDD) may be formed during the chlorine bleaching process at pulp and paper mills. CDDs are also formed during chlorination by waste and drinking water treatment plants. They can occur as contaminants in the manufacture of certain organic chemicals. CDDs are released into the air in emissions from municipal solid waste and industrial incinerators.