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IRIS

Railroad signal power supply transformer dating from the 1930's at CP-SLOPE interlocking, west of: Altoona, Pennsylvania, with a warning label indicating that it contains PCBs. Photographed on 29 April 2012 by Sturmovik. Courtesy of Wikipedia

The U.S. Environmental Protection Agency (EPA) today announced changes to its Integrated Risk Information System (IRIS) Program to improve the scientific foundation of assessments, increase transparency in the program and the process and allow the agency to produce more IRIS assessments each year.

IRIS is a human health assessment program that evaluates information on health effects that may result from exposure to environmental contaminants.

These high quality, science based health assessments are used to inform decisions to protect public health and the environment.

“EPA is committed to producing high quality scientific assessments in a timely and transparent manner,” said Lek  Kadeli, principal deputy assistant administrator of EPA’s Office of Research and Development. “The improvements announced today will further strengthen our IRIS assessments and enable the agency to better protect human health and the environment by completing more health assessments for chemicals that are being used across our country every day.”

Arsenic and its compounds are used in the production of pesticides, treated wood products, herbicides, and insecticides.: These applications are declining, however. Arsenic is notoriously poisonous to multicellular life, although a few species of bacteria are able to use arsenic compounds as respiratory metabolites. Arsenic contamination of groundwater is a problem that affects millions of people across the world. Text and photograph courtesy of Wikipedia.

Arsenic burning in the air.: Photograph by Léiem courtesy of WikipediaConsistent with recommendations from the National Research Council, EPA will now begin releasing preliminary materials and hold a public meeting early in the assessment development process to explain the criteria for selecting studies and to ensure that critical research was not omitted. Meeting with the public earlier in the process will result in more timely opportunities for the public to provide input into the assessment and comment on the information available for each chemical assessed.

EPA is also using a new document structure for IRIS assessments that is clearer, more concise and more systematic to make the information more accessible. To improve transparency, the agency is enhancing the IRIS website by providing more detailed information regarding assessment schedules, stakeholder meetings and updates on IRIS progress.

Additionally, the agency is implementing “stopping rules” for IRIS that will provide a cut­off point for accepting new data for individual IRIS assessments and raising scientific issues related to the assessment. With these changes, EPA’s goal is to increase the number of assessments being completed each year and provide more accurate assessment development timelines to the public.

The IRIS database contains crucial information about how and at what level chemicals may impact human health. When combined with exposure information, governments and private entities use IRIS to help characterize the public health risks of chemical substances, thereby supporting risk management decisions designed to protect public health.

What is IRIS?

EPA's Integrated Risk Information System (IRIS) is a human health assessment program that evaluates risk information on effects that may result from exposure to environmental contaminants. Through the IRIS Program, EPA provides the highest quality science-based human health assessments to support the Agency's regulatory activities. The IRIS database contains information for more than 540 chemical substances containing information on human health effects that may result from exposure to various substances in the environment. IRIS is prepared and maintained by the EPA’s National Center for Environmental Assessment (NCEA) within the Office of Research and Development (ORD).

The heart of the IRIS system is its collection of searchable documents that describe the health effects of individual substances and that contain descriptive and quantitative information in the following categories:

·   Noncancer effects: Oral reference doses and inhalation reference concentrations (RfDs and RfCs, respectively) for effects known or assumed to be produced through a nonlinear (possibly threshold) mode of action. In most instances, RfDs and RfCs are developed for the noncarcinogenic effects of substances.

·   Cancer effects: Descriptors that characterize the weight of evidence for human carcinogenicity, oral slope factors, and oral and inhalation unit risks for carcinogenic effects. Where a nonlinear mode of action is established, RfD and RfC values may be used.

What substances are in IRIS?

A complete alphabetical list of the substances in IRIS is available at the A to Z List of IRIS Substances on the left navigation bar.  Use Search the IRIS Database by substance name or CASRN to search for IRIS assessments for a specific substance.  Other specific search criteria are available as well. You can also search multiple substances at once using Compare IRIS Values.

How do I contact the IRIS Hotline?

Contact the IRIS Hotline via the Contact us page or at (202) 566-1676 (phone), (202) 566-1749 (fax), or hotline.iris@epa.gov (email).

Washington DC 20460 · +1-202­564­4355

More information about IRIS: http://www.epa.gov/iris

More information about the IRIS process: http://www.epa.gov/iris/process.htm

http://www.epa.gov/iris/pdfs/IRIS_PROCESS_FLOW_CHART.PDF

This news is from the U.S. Environmental Protection Agency (EPA), 31 July 2013.

Posted on the Horizon International Solutions Site 31 July 2013.