S. 4397 — Sound Science Act of 2026

This section amends the chemical testing requirements of TSCA Section 4 (15 U.S.C. 2603) as follows: (1) revises the criteria for testing rules, orders, or consent agreements to require "technically feasible methodologies" (from "methodologies") and information on "the intended and known purposes to be manufactured, processed, distributed in commerce, used, or disposed of for" the chemical; (2) eliminates the requirement in subsection (f) that EPA actions be "made without consideration of costs or other nonrisk factors"; and (3) for testing modernization under subsection (h), requires the use of relevant OECD Test Guidelines identified by EPA and listed under (h)(2)(C), updates the list at least once every 2 years (from "on a regular basis"), and expands public notice and comment to include proposed test methods and strategies for the list. (TSCA Section 4 authorizes EPA to require manufacturers and processors to test chemical substances and mixtures when health and environmental effects data are insufficient.)

This section revises the Toxic Substances Control Act (TSCA) to promote consistency between EPA chemical risk regulations and existing requirements under other federal laws, particularly the Occupational Safety and Health Act (OSHA). Specifically, it (1) amends TSCA Section 6(a) to require EPA to minimize chemical risks to the extent reasonably feasible (from eliminating such risks); (2) modifies TSCA Section 6(b)(4) risk evaluations to (A) consider only hazards and exposures more likely than not to result in unreasonable risk, sentinel exposures, and aggregate exposures only upon EPA's written determination of necessity; (B) account for exposure limits or thresholds from other federal agencies; (C) refrain from assuming noncompliance with such laws, including OSHA standards; (D) extend the public comment period on draft evaluations to 60 days (from 30); and (E) establish a 30-day interagency review process for federal feedback on critical uses, alternatives, and supply chain impacts prior to public comment; (3) directs EPA, in TSCA Section 6(c)(2)(B), to select cost-effective regulatory requirements that minimize unreasonable risk without creating greater risks, factoring in OSHA standards; and (4) expands TSCA Section 26(k)'s definition of reasonably available information to include OSHA requirements, prohibitions, and restrictions. (Thus, these changes limit EPA's regulatory scope by aligning it with OSHA workplace protections and other federal standards, potentially reducing duplicative or conflicting rules for chemical manufacturers, users, and workers.)

This section requires the EPA Administrator to publicly disclose any scientific assessment relied on in conducting a risk evaluation for a chemical substance under TSCA Section 6(b), in addition to existing requirements for information on health and environmental effects. (Thus, this expands transparency and accountability for EPA's chemical risk evaluations, which determine whether substances present unreasonable risks of injury to human health or the environment.)

This section amends scientific review provisions in section 26 of the Toxic Substances Control Act (TSCA) as follows: (1) in subsection (h), adds to judicial review criteria three new factors—(a) the extent to which EPA scientific assessments or risk evaluations are consistent with standards in subsection (h) or weighting in subsection (i); (b) for worker protection standards, results of consultations with federal agencies (including OSHA) and experts in industrial hygiene, toxicology, engineering, and process safety; and (c) interagency comments under TSCA section 6(b)(4)(F)(viii) from the Departments of Defense, Energy, and Agriculture and OSHA; and (2) in subsection (o), requires the Science Advisory Committee, when reviewing risk evaluations under TSCA section 6(b), to conduct an in-person peer review with at least 30 days for reviewers to assess the evaluation, underlying science, risk determinations, and scientific assessments. (As background, the committee advises EPA on the scientific and technical merit of chemical risk evaluations that determine whether substances present unreasonable risks.)