EPA Authority Under the Toxic Substances Control Act

The Toxic Substances Control Act (TSCA), enacted in 1976 and substantially amended by the Frank R. Lautenberg Chemical Safety for the 21st Century Act in 2016, grants the Environmental Protection Agency broad authority to evaluate, regulate, and restrict chemical substances in commerce. This page covers the scope of that authority, the mechanisms EPA uses to exercise it, scenarios that trigger regulatory action, and the boundaries that define what EPA can and cannot do under TSCA. Understanding these parameters matters for chemical manufacturers, importers, processors, distributors, and industrial users subject to TSCA's requirements. The EPA's chemical safety program operates largely under this statute.


Definition and scope

TSCA authorizes EPA to regulate chemical substances and mixtures that present an unreasonable risk to human health or the environment (15 U.S.C. §§ 2601–2697). The statute covers all chemical substances manufactured, imported, processed, or distributed in the United States, with specific exclusions for pesticides (regulated under FIFRA), food additives, drugs, cosmetics, and nuclear materials.

TSCA's scope divides into six primary subchapters:

  1. Control of Toxic Substances (Subchapter I) — The core regulatory framework governing chemical risk evaluation and risk management.
  2. Asbestos Hazard Emergency Response (Subchapter II) — Specific rules for asbestos in school buildings.
  3. Indoor Radon Abatement (Subchapter III) — Guidance and grant authority for radon mitigation.
  4. Lead Exposure Reduction (Subchapter IV) — Standards for lead-based paint in pre-1978 housing and renovation activities.
  5. Healthy High-Performance Schools (Subchapter V) — Coordination of school environmental health programs.
  6. Mercury (Subchapter VI) — Reporting and recordkeeping for mercury-containing products.

The 2016 Lautenberg amendments fundamentally changed the law's operational character. Before 2016, EPA faced procedural hurdles so significant that the agency was able to finalize restrictions on only five chemical substances under Section 6 in the statute's first four decades. The 2016 amendments mandated a workplan, set deadlines, and required EPA to evaluate at least 10 existing chemicals at any given time.


How it works

EPA's authority under TSCA operates through four primary mechanisms: inventory management, pre-manufacture notification, risk evaluation, and risk management rulemaking.

Chemical Inventory and Pre-Manufacture Notification (PMN)
All chemical substances in U.S. commerce must appear on the TSCA Chemical Substance Inventory, which contains more than 86,000 substances (EPA TSCA Chemical Substance Inventory). Manufacturers or importers of a new chemical not on the inventory must submit a PMN to EPA at least 90 days before manufacture or import begins. EPA reviews the submission, and if risks cannot be evaluated due to insufficient data, the agency may issue a Significant New Use Rule (SNUR) or take action to restrict the chemical.

Risk Evaluation
For existing chemicals, EPA conducts systematic risk evaluations under Section 6. The process follows a structured sequence:

  1. Scoping — identifying the chemical's conditions of use and exposed populations
  2. Hazard assessment — reviewing toxicological and ecotoxicological data
  3. Exposure assessment — estimating human and environmental exposure pathways
  4. Risk characterization — integrating hazard and exposure findings
  5. Final risk determination — a binary finding of "unreasonable risk" or no unreasonable risk

If EPA determines unreasonable risk exists, the agency must initiate rulemaking to address that risk within two years of the final determination, with a possible one-year extension (15 U.S.C. § 2605(c)(1)(A)).

Risk Management Rulemaking
Under Section 6(a), EPA may prohibit or limit the manufacture, processing, distribution, use, or disposal of a chemical substance. Restrictions range from labeling requirements and concentration limits to outright bans. Methylene chloride in paint strippers and trichloroethylene (TCE) in multiple applications have been subject to Section 6 actions following the Lautenberg amendments.

Reporting and Recordkeeping
Sections 8(a) and 8(e) require companies to report chemical data and to notify EPA immediately of substantial risk information. EPA's Toxic Release Inventory, while primarily a EPCRA program, intersects with TSCA data obligations in practice.


Common scenarios

Several situations routinely invoke TSCA authority:


Decision boundaries

TSCA authority has defined limits that distinguish it from EPA's authority under other statutes, such as the Clean Air Act or RCRA.

What TSCA covers vs. what it does not:

Aspect Within TSCA Authority Outside TSCA Authority
Substance type Industrial chemicals, mixtures Pesticides, drugs, food additives, nuclear materials
Lifecycle stage Manufacture through disposal Occupational exposure limits (OSHA primary jurisdiction)
Geographic scope U.S. manufacture and import Foreign-only production with no U.S. nexus
Risk standard "Unreasonable risk" (risk-only basis post-2016) Cost-benefit balancing required under other statutes

A critical boundary established by the Lautenberg amendments is that EPA must base risk determinations solely on risk, without considering costs or non-risk factors. Cost and feasibility considerations enter only during the risk management phase when selecting among regulatory options. This distinguishes TSCA's current framework from the pre-2016 standard that courts found effectively paralyzed EPA's Section 6 authority — as seen in Corrosion Proof Fittings v. EPA, 947 F.2d 1201 (5th Cir. 1991), which invalidated EPA's attempted asbestos ban under the old standard.

Additionally, TSCA preemption provisions under Section 18 limit states from imposing chemical regulations that are identical to or less stringent than final EPA TSCA rules, though states retain authority to act before EPA finalizes a rule or in areas EPA has not addressed. The relationship between EPA and state regulators is particularly consequential under TSCA given California's longstanding independent chemical regulatory activity. A full overview of EPA's statutory authorities across programs is available on the EPA Authority site index.