The carcinogenic potencies of 2,3,7,8-tetrachlorodibenzo-p-dioxin: Letting the data speak for themselves
- Cambridge Environmental Inc., MA (United States)
The authors analyze here the dose-response data generated from the seminal bioassay of 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) in Sprague-Dawley rats, reported by Kociba and coworkers. That chronic toxicity and oncogenicity study showed 2,3,7,8-TCDD to increase the incidence of certain tumors, while decreasing the incidence of others. Further, results in female rats were markedly different from those in male rats--a result ascribed to the dependence of dioxin on estrogen for some of its toxic effects. For each sex, the authors analyze each tumor type on which 2,3,7,8-TCDD has, or might have, an effect, whether positive, negative, or neutral. After generating dose-response relationships for each tumor type, the authors combine them. The combination involves simply adding the slopes of each tumor-specific dose-response relationship. They perform separate analyses for each set of dose-ranges. They also calculate upper (and lower) bounds on the maximum likelihood estimates, using the upper 95th percentile estimates for the slopes of the net dose-response relationships as conservative estimates of carcinogenic potency.
- OSTI ID:
- 495335
- Report Number(s):
- CONF-9504119-; TRN: IM9731%%28
- Resource Relation:
- Conference: Air & Waste Management Association international speciality conference on thermal treatment and waste-to-energy technologies for solid waste management, Washington, DC (United States), 18-21 Apr 1995; Other Information: PBD: 1996; Related Information: Is Part Of Solid waste management: Thermal treatment and waste-to-energy technologies. VIP-53; Kilgroe, J.D. [comp.] [National Risk Management Research Lab., Research Triangle Park, NC (United States)]; PB: 981 p.
- Country of Publication:
- United States
- Language:
- English
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