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Inorganic Arsenic Workshop (Jan 2013)

EPA is currently revising its Integrated Risk Information System (IRIS) assessment of inorganic arsenic. This assessment addresses both noncancer and cancer human health effects that may result from chronic inhalation exposure to this chemical. To facilitate discussion of several scientific issues pertinent to the assessment, EPA hosted a state-of-the-science workshop. This workshop was open to the public, broadcast by webinar/teleconference, and took place in Arlington, VA.

Workshop Overview:

EPA is developing a plan for drafting a new IRIS Toxicological Review of Inorganic Arsenic. The first planning step is determining the scope of the Toxicological Review. The scope transparently communicates why the Toxicological Review is being performed and what it will include or exclude.

The meeting consisted of 5 sessions of panel discussions focused on a series of charge questions. Lead discussants briefly summarized the available data to address the questions and facilitate discussion with other panelists. Once the panel discussion is over, participants attending the meeting in person or remotely via webinar/teleconference were given the opportunity to ask questions or provide comments within the time constraints of the meeting. In addition to discussions after the panel sessions, time was allotted for participants attending the meeting in person or remotely via webinar/teleconference to provide additional comments.

Meeting Objective:

This workshop gave stakeholders the opportunity to share their views about the scope on the EPA's toxicological review of inorganic arsenic. All meeting participants were given the opportunity to comment on their needs for the Toxicological Review, the current state of scientific information that should be considered when developing the Toxicological Review, and the potential impacts of the Toxicological Review.

Final Reports:

EPA produced a planning and scoping summary document at the end of this public workshop. This planning and scoping summary document aims to communicate how EPA will produce the assessment while meeting the needs of the Agency and the American people. 

Workshop Materials:

Inorganic Arsenic Workshop Final Agenda (8 pp, 195 K, About PDF)


Related Links:

Information relevant to the development of a toxicological review of iAs include the following publications:

  1. Science and Decisions (NAS, 2009)
  2. Review of IRIS Formaldehyde Assessment (NAS, 2011)
  3. SAB Reviews of draft iAs Assessments (SAB, 2011: SAB, 2007)
  4. Arsenic in Drinking Water; Arsenic in Drinking Water Update (NAS, 2001; NAS, 1999)
  5. 2005 EPA Cancer Guidelines (including mode of action framework)
  6. 2006/2008 IPCS Mode of Action Framework
  7. EPA’s Risk Characterization Handbook