Arsenic, inorganic

CASRN 7440-38-2

IRIS Toxicological Review for Inorganic Arsenic (Scoping and Problem Formulation Materials, 2012)

Notice - This site contains archived material(s).

Archive disclaimer
Archived files are provided for reference purposes only. The file was current when produced, but is no longer maintained and may now be outdated. Persons with disabilities having difficulty accessing archived files may contact the NCEA Webmaster for assistance. Please use the contact form if you need additional assistance.


In November 2012, EPA released scoping and problem formulation materials for the IRIS assessment of inorganic arsenic for public comment and discussion. The scoping information was based on input from EPA's program and regional offices and was provided for informational purposes.

During problem formulation, the IRIS Program was looking for input from the scientific community and the general public as it frames the specific scientific questions for the systematic reviews that it will conduct to develop the assessments.


Janice Lee,  Ph:  919-541-9458,  Email:

J. Allen Davis,  Ph:  919-541-3789,  Email:

Top of Page


Inorganic arsenic is used for hardening copper and lead alloys. It also is used in glass manufacturing as a decolorizing and refining agent, as a component of electrical devices, in the semiconductor industry, and as a catalyst in the production of ethylene oxide. Arsenic compounds are used as a mordant in the textile industry, for preserving hides, as medicinals, pesticides, pigments, and wood preservatives. Arsenic is also found naturally in the environment and is typically present in soil and water at detectable levels. Sources of human exposure to inorganic arsenic include drinking water, diet, air, and soils (which can contain naturally occurring arsenic or contamination from anthropogenic sources).


Date Description
1988EPA published the IRIS Health Hazard Assessment for Inorganic Arsenic.
1999NRC reviewed the 1988 IRIS assessment and the available health data for inorganic arsenic and made recommendations for updating the cancer assessment in Arsenic in Drinking Water.
2001NRC updated the NRC (1999) report and evaluated the toxicological risk and health effects of arsenic as relevant to the 2001 Arsenic Rule in Arsenic in Drinking Water – 2001 Update. Also in 2001, the NRC reviewed the 2001 Primary Drinking Water Standard for inorganic Arsenic and made recommendations for applying epidemiologic data in the cancer health assessment.
2003EPA started a reassessment of the IRIS Toxicological Review.
Jul 2005EPA released the draft IRIS inorganic arsenic assessment in July 2005 for public comment and peer review.
Jun 2007The Science Advisory Board (SAB) posted a response to the 2005 EPA reassessment of inorganic arsenic (cancer).
Oct 2008A draft IRIS Toxicological Review for Inorganic Arsenic (cancer) was submitted to OMB for interagency review.
Jun 2009EPA hosted an interagency science consultation on the draft IRIS Toxicological Review of Inorganic Arsenic.
Feb 2010EPA released the draft IRIS Toxicological Review for Inorganic Arsenic (cancer) to SAB and simultaneously to the public for review and comment, focusing on EPA’s responses to the SAB (2007) report.
Oct 2010SAB announced public teleconference to conduct a quality review of the draft report to be held on November 22, 2010. [Federal Register Oct 25, 2010], and SAB completed its review of the draft assessment.
2011Congress directed EPA to contract with the National Research Council (NRC) to review the draft assessment.
Nov 2012EPA released scoping and problem formulation materials for the IRIS assessment of inorganic arsenic for public comment and discussion.
Jan 2013EPA held a public planning and scoping meeting for development of a new IRIS Toxicological Review of Inorganic Arsenic.


EPA will host a public science meeting to discuss these documents and update the draft assessment.

Top of Page


This download(s) is distributed solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. It has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency determination or policy.


Comments on the assessment may be submitted and reviewed using the Docket ID EPA-HQ-ORD-2012-0830

Top of Page