Chlorinated Dibenzo-p-dioxins (CDDs)


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.

Community Members
Community Members

ToxFAQs - Fact sheet that answers the most frequently asked questions about a contaminant and its health effects.

Public Health Statement - Summary about a hazardous substance taken from Chapter One of its respective ATSDR Toxicological Profile.

National Report on Human Exposure to Environmental Chemicals - Provides an ongoing assessment of the exposure of the U.S. population to environmental chemicals using biomonitoring.

Toxicological and Health Professionals
Toxicological and Health Professionals

Toxicological Profile - Succinctly characterizes the toxicologic and adverse health effects information for a hazardous substance.

Addendum to the Profilepdf icon[1587 KB] - Addendum to the Toxicological Profile for Chlorinated Dibenzo-p-dioxins (CDDs) (November 2012)

Minimal Risk Levels (MRL) - The MRL is an estimate of the daily human exposure to a hazardous substance that is likely to be without appreciable risk of adverse, non-cancer health effects over a specified duration of exposure. The information in this MRL serves as a screening tool to help public health professionals decide where to look more closely to evaluate possible risk of adverse health effects from human exposure.

Interaction Profiles - Succinctly characterizes the toxicologic and adverse health effects information for mixtures of hazardous substances.

Page last reviewed: February 10, 2021