Science Inventory

IRIS Toxicological Review of Thallium and Compounds (External Review Draft)


In April 2008, EPA has announced the External Peer Review Panel Workshop in an April 8, 2008 Federal Register notice. Prior to this, EPA announces the release of the Toxicological Review of Thallium in a Feb 15, 2008 Federal Register notice. This draft assessment was provided for public viewing and comment. Public comments received on the Toxicological Review within 60 days after the release of the FRN were provided to the external peer reviewers for their consideration. Any comments not received within the requested time period may be considered by EPA in their revisions. The date and location of the external peer review meeting were provided in a separate announcement.


U.S. EPA. IRIS Toxicological Review of Thallium and Compounds (External Review Draft). U.S. Environmental Protection Agency, Washington, DC, EPA/635/R-08/001, 2008.


EPA is undertaking an Integrated Risk Information System (IRIS) health assessment for thallium and compounds. IRIS is an EPA database containing Agency scientific positions on potential adverse human health effects that may result from chronic (or lifetime) exposure to chemicals in the environment. IRIS contains chemical-specific summaries of qualitative and quantitative health information in support of two steps of the risk assessment paradigm, i.e., hazard identification and dose-response evaluation. IRIS assessments are used in combination with specific situational exposure assessment information to evaluate potential public health risks associated with environmental contaminants.


Thallium compounds are used in the semiconductor industry, the manufacture of optic lenses and low-melting glass, low-temperature thermometers, alloys, electronic devices, mercury lamps, fireworks, and imitation germs, and clinically as an imaging agent in the diagnosis of certain tumors. EPA's assessment of noncancer health effects and carcinogenic potential of thallium compounds was last prepared and added to the IRIS database between 1988 and 1990. The IRIS program is preparing an assessment that will incorporate current health effects information available for thallium and compounds, and current risk assessment methods. The IRIS assessment for thallium compounds will consist of a Toxicological Review and IRIS Summary. The Toxicological Review is a critical review of the physiochemical and toxicokinetic properties of a chemical, and its toxicity in humans and experimental systems. The assessment will present reference values for the noncancer effects of thallium compounds (RfD and Rfc), and a cancer assessment. The Toxicological Review and IRIS Summary have been subject to Agency review, Interagency review, and external scientific peer review. The final product will reflect the Agency opinion on the overall toxicity of thallium and compounds.


Volume 2: Range Finding (90-Day Study) Part 1   (PDF,299 pp, 57498 KB,  about PDF)

Consolidated Comments from the External Peer Review (Final)   (PDF,76 pp, 257 KB,  about PDF)

Compilation of Reviewer Comments and Responses to Charge Questions (Reported by Midwest Research Institute)   (PDF,10 pp, 43 KB,  about PDF)

Charge to External Peer Reviewers   (PDF,3 pp, 21 KB,  about PDF)

Toxicological Review of Thallium (External Review Draft)   (PDF,86 pp, 474 KB,  about PDF)

Volume 1: Range Finding (14-Day Study)   (PDF,55 pp, 29004 KB,  about PDF)

FR Notice: Feb 15, 2008   Exit

Compilation of Reviewer Comments and Responses to Charge Questions (Reported by Midwest Research Institute)   (PDF,10 pp, 43 KB,  about PDF)

FR Notice: Apr 8, 2008   Exit

Volume 2: Range Finding - Part 2 (Appendix IV)   Exit   (PDF,255 pp, 150097 KB,  about PDF)

Record Details:

Product Published Date: 09/30/2009
Record Last Revised: 02/02/2017
OMB Category: Influential
Record ID: 188304