S. 623 (119th)Bill Overview

No IRIS Act of 2025

Environmental Protection|Environmental Protection
Cosponsors
Support
Republican
Introduced
Feb 18, 2025
Discussions
Bill Text
Current stageCommittee

Read twice and referred to the Committee on Environment and Public Works.

Introduced
Committee
Floor
President
Law
Congressional Activities
01 · The brief
Plain-English summaryWhat this bill actually does

The bill prohibits the EPA Administrator from using any assessment produced by the EPA’s Integrated Risk Information System (IRIS) program as a basis to develop, finalize, or issue rules or regulations, to carry out regulatory, enforcement, or permitting actions, or to inform air toxics assessments, mapping, or screening tools.

Why people may split

Progressives emphasize public-health harms from blocking IRIS.

Watch point

Narrow, administratively focused bills often advance in the House, but controversy over science/regulation raises opposition risk.

The bill prohibits the EPA Administrator from using any assessment produced by the EPA’s Integrated Risk Information System (IRIS) program as a basis to develop, finalize, or issue rules or regulations, to carry out regulatory, enforcement, or permitting actions, or to inform air toxics assessments, mapping, or screening tools.

Passage30/100

Narrow and administratively focused but ideologically charged and lacking compromise features, reducing cross-chamber and cross-branch appeal.

CredibilityPartial

How solid the drafting looks.

Contention75/100

Progressives emphasize public-health harms from blocking IRIS.

02 · What it does

Who stands to gain, and who may push back.

Likely benefits vs burdens50% / 50%
Likely helpedCities

These are examples from the analysis, not a ranked list of the most-affected groups.

Likely helped
  • Potential benefitReduces regulatory compliance burdens by preventing IRIS-based standards that could trigger new controls.
  • Potential benefitSupports use of alternative data sources that proponents may deem more current or transparent.
  • Potential benefitMay lower perceived regulatory risk and litigation tied specifically to IRIS-based determinations.
Likely burdened
  • CitiesReduces EPA access to a centralized, peer-reviewed toxicity assessment resource used in health-based rulemaking.
  • Potential burdenCould delay or weaken pollution controls, increasing population exposures and potential adverse health outcomes.
  • Potential burdenMay force reliance on disparate alternative studies, increasing regulatory inconsistency and legal vulnerability.
03 · Why people split

Why the argument around this bill splits.

Progressives emphasize public-health harms from blocking IRIS.
Progressive10%

Likely to view the bill as a rollback of an EPA scientific tool that supports health-based regulation.

They will argue it undermines public-health protections by barring use of agency risk assessments in rulemaking and enforcement.

Likely resistant
Centrist50%

Will have mixed views: sympathetic to concerns about scientific rigor and legal defensibility, but worried about public-health gaps.

They will weigh procedural improvements against the risk of regulatory paralysis.

Split reaction
Conservative85%

Likely to view the bill favorably as a constraint on EPA regulatory power and as a measure to prevent agency reliance on possibly over-conservative internal assessments.

They will frame it as reducing regulatory burden on industry.

Leans supportive
04 · Can it pass?

The path through Congress.

Introduced

Reached or meaningfully advanced

Committee

Reached or meaningfully advanced

Floor

Still ahead

President

Still ahead

Law

Still ahead

Passage likelihood30/100

Narrow and administratively focused but ideologically charged and lacking compromise features, reducing cross-chamber and cross-branch appeal.

Scope and complexity
24%
Scopenarrow
24%
Complexitylow
Why this could stall
  • Whether IRIS assessments are precisely defined for enforcement
  • Effect on existing or in-progress EPA rules is unclear
05 · Recent votes

Recent votes on the bill.

No vote history yet

The bill has not accumulated any surfaced votes yet.

06 · Go deeper

Go deeper than the headline read.

Included on this page

Progressives emphasize public-health harms from blocking IRIS.

Narrow and administratively focused but ideologically charged and lacking compromise features, reducing cross-chamber and cross-branch appe…

Unlocked analysis

Pro readers get the full perspective split, passage barriers, legislative design review, stakeholder impact map, and lens-based policy tradeoff analysis for No IRIS Act of 2025.

Go beyond the headline summary with full stakeholder mapping, legislative design analysis, passage barriers, and lens-by-lens tradeoff breakdowns.

Perspective breakdownsPassage barriersLegislative design reviewStakeholder impact map
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