The No IRIS Act of 2025 would restrict the Environmental Protection Agency from using assessments generated by the Integrated Risk Information System (IRIS) in its rulemaking, enforcement actions, or related mapping and screening tools. Introduced by Rep.
Grothman in the 119th Congress, the bill frames IRIS as a dependency for federal risk assessments that it seeks to curtail. The proposal is narrow in scope but carries potential implications for how risk information is generated and applied across EPA policies and state implementations.
By limiting a long-standing input into federal risk characterization, the bill would force EPA and related decision-makers to rely on alternative risk assessment inputs or frameworks. Supporters argue the measure reduces reliance on a single agency-driven system; opponents warn it could slow or complicate regulatory development and undermine consistency across programs.
The bill’s reach is specific to IRIS-derived assessments and does not otherwise alter EPA’s broader regulatory authorities.
At a Glance
What It Does
The Administrator of the EPA may not use any IRIS-generated assessment for rulemaking, enforcement or permitting actions, or to inform air toxics assessments or mapping/screening tools.
Who It Affects
EPA rulemakers, federal regulators, and states that implement EPA guidance; industries regulated under EPA rules that historically used IRIS as a reference point.
Why It Matters
It redefines the baseline risk information that informs federal regulation, potentially shifting how health risk thresholds are determined and how quickly standards can be updated. This matters to compliance professionals who monitor EPA risk-based criteria and to policymakers weighing regulatory predictability versus scientific inputs.
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What This Bill Actually Does
The bill targets a specific science tool—the Integrated Risk Information System (IRIS) used by the EPA to support risk assessments that inform rules and enforcement. If enacted, the Administrator may not rely on IRIS assessments to develop, finalize, or issue rules; to carry out regulatory, enforcement, or permitting actions; or to underpin air toxics assessments and related mapping tools.
The language is explicit: Notwithstanding any other law, the IRIS input can’t be used by EPA for these purposes.
What this means in practice is that EPA would need to source risk information from other frameworks or develop alternative, equivalent inputs for health risk analyses. The bill does not remove EPA’s authority to regulate; it removes a central, standardized input that has historically shaped many risk thresholds.
State agencies and regulated industries should anticipate shifts in how risk is quantified for air toxics and other EPA-driven programs, potentially affecting timelines, consistency, and the stringency of standards. In terms of implementation, the bill’s scope suggests a transition period would be necessary for agencies to identify or validate substitute risk inputs, align with new frameworks, and address any legal or administrative questions about reliance on non-IRIS data.
The practical impact will hinge on how EPA, states, and interested stakeholders adapt to alternative risk information sources.
The Five Things You Need to Know
The bill prohibits EPA from using any IRIS assessment in rulemaking or regulation.
It forbids IRIS use in any regulatory, enforcement, or permitting action by the EPA.
It bars IRIS-based information from informing air toxics assessments or mapping/tools.
The act is titled the No IRIS Act of 2025 and was introduced in the 119th Congress.
It was introduced by Rep. Glenn Grothman and referred to Energy and Commerce, Agriculture, and Transportation and Infrastructure committees.
Section-by-Section Breakdown
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Short title
This act may be cited as the “No IRIS Act of 2025” or the “No Industrial Restrictions in Secret Act of 2025.” The citation provides the legal shorthand by which the measure will be referenced in subsequent regulatory and statutory work.
Prohibition on using IRIS for rulemaking
Notwithstanding any other provision of law, the EPA Administrator may not use any IRIS assessment to develop, finalize, or issue a rule or regulation. This prohibition directly removes IRIS as a baseline input in the early and mid-stages of rule development, potentially altering the risk thresholds agencies rely on when drafting standards.
Prohibition on using IRIS for enforcement actions
The bill prohibits the use of IRIS assessments to carry out regulatory, enforcement, or permitting actions. In practice, this could complicate how EPA identifies risk and enforces compliance if IRIS-derived benchmarks were historically used to justify actions.
Prohibition on using IRIS to inform mapping or screening tools
IRIS assessments may not be used to inform air toxics assessments or other mapping or screening tools. This expands the ban from rulemaking and enforcement into the analytical tools agencies use for screening and geographic risk visualization, potentially affecting how risks are identified and prioritized.
This bill is one of many.
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Every bill creates winners and losers. Here's who stands to gain and who bears the cost.
Who Benefits
- Oil and gas sector and other regulated industries that may face less stringent or differently framed risk thresholds by removing IRIS as a default input.
- State environmental agencies that gain flexibility to craft risk assessments and standards tailored to their jurisdictions.
- Industry trade associations seeking regulatory predictability and a diversified risk-input landscape.
- Regulatory risk-management consultancies that adapt to alternative risk frameworks and compliance pathways.
Who Bears the Cost
- Public health and environmental justice advocates concerned that reduced reliance on IRIS could weaken health protections.
- Small and medium-sized regulated entities facing transition costs to adopt new risk inputs and adjust compliance programs.
- Some state and local agencies may incur costs to develop or validate substitute risk assessment methods.
- EPA program offices may face administrative and legal questions as they transition away from IRIS-based analyses.
Key Issues
The Core Tension
The central dilemma is whether eliminating IRIS as a core input will yield more flexible, adaptive regulation or undermine consistent health protections and predictability in federal rules.
The No IRIS Act creates a policy shift away from a single, standardized risk input toward broader reliance on alternative risk assessment frameworks. While this could improve regulatory flexibility and reduce over-reliance on one system, it raises questions about the consistency, transparency, and comparability of risk evaluations across jurisdictions.
Implementation questions include what replaces IRIS as the default input, how EPA validates new risk parameters, and how to prevent regulatory gaps during the transition. The bill does not specify timelines or funding for building new analytical capabilities, which could translate into implementation challenges for agencies and regulated entities.
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