IRIS refers to the Integrated Risk Information System, a human health assessment program that "evaluates quantitative and qualitative risk information on effects that may result from exposure to environmental contaminants...The information in IRIS is intended for those without extensive training in toxicology, but with some knowledge of health sciences."
In their continuing efforts to improve the oft-maligned program, EPA on July 12, 2011 announced plans "to further strengthen and streamline" IRIS and implement the April 2011 recommendations by the National Academy of Sciences. According to EPA:
The most recent improvements include: reducing volume and redundancy of assessments; fuller discussion of methods and concise statements of criteria used in studies for hazard evaluation; clearer articulation of the rationale and criteria for screening studies; implementing uniform approaches for choosing studies and evaluating their findings; and describing the determinants of weight that were used in synthesizing the evidence. In addition, EPA is working to set up a dedicated advisory committee that will exclusively focus on the quality, transparency and scientific rigor of IRIS assessments. EPA will also create a peer consultation step early in the development of major IRIS assessments. Continually improving the IRIS program is an ongoing priority for the Agency, and these efforts work towards this goal.
The full testimony of David Trimble can be read here.