IRIS

2,3,7,8-Tetrachlorodibenzo-p-dioxin

Noncancer Assessment

Reference Dose for Oral Exposure (RfD) (PDF) (16 pp, 150 K) Last Updated: 02/17/2012

System RfD (mg/kg-day) Basis PoD Composite UF Confidence
Reproductive 7 x 10 -10 Decreased sperm count and motility in men exposed to TCDD as boys / Increased TSH in neonates LOAEL (ADJ): 2 x 10-8
mg/kg-day
30 High
Endocrine, Developmental, Reproductive 7 x 10 -10 Decreased sperm count and motility in men exposed to TCDD as boys / Increased TSH in neonates LOAEL (ADJ): 2 x 10-8
mg/kg-day
30 High

 


Reference Concentration for Inhalation Exposure (RfC) (PDF) (16 pp, 150 K)
Not assessed under the IRIS Program.

 

Cancer Assessment

Weight of Evidence for Cancer (PDF) (16 pp, 150 K) Last Updated: 02/17/2012
Assessment underway at the time of the last significant revision.

Quantitative Estimate of Carcinogenic Risk from Oral Exposure (PDF) (16 pp, 150 K)

Not assessed under the IRIS Program.

Quantitative Estimate of Carcinogenic Risk from Inhalation Exposure (PDF) (16 pp, 150 K)

Not assessed under the IRIS Program.


Feb 2012: EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (Volume 1) (Interagency Science Discussion Draft) (Report)

May 2010: EPA's Reanalysis of Key Issues Related to Dioxin Toxicity and Response to NAS Comments (External Review Draft) (Report)

Feb 2010: EPA's Response to Health Risks from Dioxin and Related Compounds Evaluation of the EPA Reassessment Published by the National Research Council of the National Academies (Interagency Science Consultation Draft) (Report)

May 2009: EPA's Science Plan For Activities Related To Dioxins In the Environment (Other)

Nov 2008: 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (TCDD) Dose-Response Studies: Preliminary Literature Search Results and Request for Additional Studies (Other)

Oct 2004: Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) and Related Compounds National Academy Sciences (External Review Draft) (2004) (Report)

Sep 2000: Exposure and Human Health Reassessment of 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Tcdd) and Related Compounds: Science Advisory Board (External Review Draft) (2000) (Report)

Sep 1994: Dioxin Exposure Initiative (Dei) (Other)

Mar 1989: INTERIM PROCEDURES FOR ESTIMATING RISKS ASSOCIATED WITH EXPOSURES TO MIXTURES OF CHLORINATED DIBENZO-P-DIOXINS AND -DIBENZOFURANS (CDDS AND CDFS) AND 1989 UPDATE (Report)

Sep 1985: Health Assessment Document for Polychlorinated Dibenzo-P-Dioxins (1985) (Report)

Apr 1985: Health Risk Assessment Approach for 2,3,7,8-Tetrachlorodibenzo-P-Dioxin (Draft) (Report)

Sep 1984: HEALTH EFFECTS ASSESSMENT FOR 2,3,7,8-TETRACHLORODIBENZO-P-DIOXIN (1984) (Report)

Additional EPA toxicity information may be available by visiting the following sites:

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