The TSCA 8(d) Deadline Lands Today and EPA Hasn't Decided: What 16-Chemical Manufacturers Actually Do on May 22, 2026

Today is May 22, 2026. As of this morning, that is the statutory deadline for manufacturers and importers of 16 named chemicals to submit unpublished health and safety studies to the Environmental Protection Agency (EPA) under the Toxic Substances Control Act (TSCA) Section 8(d) Health and Safety Data Reporting Rule. EPA has proposed extending that deadline to May 21, 2027, the comment period closed April 29, and the Agency has stated it “anticipates taking appropriate action” — but no final rule has published, no enforcement discretion has been formalized, and the regulation on the books still says today. If your facility handles any of the 16 substances and you have not made a documented decision about what to do this week, you are operating in a position no environmental, health, and safety (EHS) lead wants to defend later.

This is not a hypothetical. The first extension already happened — March 13, 2025 slid to May 22, 2026 via 90 FR 24348 last June. The second extension is on paper but not in force. What follows is what compliance officers at chemical manufacturers (NAICS Subsector 325) and petroleum refineries (NAICS 32411) need to know about the rule, the deadline, the penalty exposure, and how a 12-month window — if EPA grants one — should actually be used.

What the Rule Actually Requires

EPA finalized the TSCA Section 8(d) Health and Safety Data Reporting Rule on December 13, 2024 (89 FR 100823), adding 16 chemical substances to 40 CFR Part 716 Subpart B. The rule requires any manufacturer or importer of a listed substance — going back ten years before the December 2024 effective date — to submit copies or lists of unpublished health and safety studies they sponsored, initiated, or know about. Studies in scope cover environmental effects, physicochemical properties, occupational exposure, general-population exposure, consumer exposure, and environmental exposure, per 40 CFR 716.30.

The 16 chemicals on the list include some of the most-handled substances in the chemical manufacturing and refining sectors: benzene, naphthalene, styrene, ethylbenzene, acrylonitrile, vinyl chloride, hydrogen fluoride, bisphenol A (BPA), 4,4′-methylene bis(2-chloroaniline) or MBOCA, acetaldehyde, aniline, 4-tert-octylphenol, 6PPD, tribromomethane, triglycidyl isocyanurate, and others on the final substance list. A petroleum refinery that handles benzene, ethylbenzene, and naphthalene as routine inventory is in scope on three counts. A polymer producer with a styrene line is in scope. A specialty chemical operation running aniline derivatives is in scope.

The submission itself runs through EPA’s Central Data Exchange (CDX) using the 8(d) module. Submitters must identify confidential business information (CBI) claims at the time of submission and substantiate them under 40 CFR Part 703 procedures. The rule is a one-time backward look — it does not require generating new studies. It requires inventorying ten years of unpublished work and getting it to EPA in the prescribed format. That distinction matters because most plants underestimate how long the inventory takes and overestimate how long the submission itself takes.

Who Has to Submit — And Who Quietly Doesn’t Realize They’re In Scope

The rule applies to manufacturers (including importers) of any listed substance classified under NAICS Subsector 325 (Chemical Manufacturing) or NAICS 32411 (Petroleum Refineries). The applicability test runs three levels deep, and the second and third levels are where most plants miss themselves.

Level one: do you currently manufacture or import a listed chemical? Easy to answer.

Level two: did you manufacture, import, or propose to manufacture or import a listed chemical at any point in the ten years preceding December 13, 2024? Harder. R&D pilots count. Discontinued product lines count. Acquired sites that historically produced a listed chemical count. A manufacturer that exited a vinyl chloride line in 2017 still has a 2014–2024 reporting window of studies to inventory.

Level three: are you producing a listed chemical as a byproduct or impurity, or importing it as a component of an article? The byproduct question catches operations that have never identified themselves as manufacturers of the listed substance because they think of it as a side stream. The article-importer question is where the proposed extension may eventually carve scope — but as of today the rule reads broadly.

Small manufacturer exemption: 40 CFR 704.3 excludes entities with total sales under $12 million combined with parent, or total sales under $120 million combined with single-site annual production under 100,000 pounds. The exemption sounds generous until you read the carve-out — it does not apply if the substance is under a TSCA Section 4, 5, or 6 rule, order, or civil action. Most of the 16 listed chemicals are candidates for or already subject to risk evaluations under Section 6, which voids the small-manufacturer exemption for those substances. A plant that runs the small-manufacturer math without checking the Section 6 status is reading the exemption wrong.

The practical scoping question for a plant manager: walk your tank farm, your raw-material receiving log, your byproduct stream list, and your article-component bill of materials. If any of the 16 listed chemicals appear, and you cannot affirmatively rule out the past-ten-year window or the Section 6 carve-out, you are in scope and you need a decision about today’s deadline.

The Penalty Stack: $49,772 Per Violation, Per Day

TSCA Section 16 civil penalties under 15 USC § 2615 currently run up to $49,772 per violation per day, per the January 8, 2025 inflation adjustment. Each chemical can be a separate violation. Each missing study can be a separate violation. Each day of non-submission is a separate day. The theoretical math compounds fast — a refinery in scope on five substances with 40 unpublished studies could, on paper, face a six-figure-per-day exposure stack.

That theoretical maximum is not what EPA typically assesses. Under the Interim Consolidated Enforcement Response and Penalty Policy issued January 17, 2025, EPA scales actual penalties by violation gravity, history, ability to pay, good-faith effort, and economic benefit of non-compliance. A first-time, good-faith late submission during a reconsideration window is not, in real life, a $49,772/day exposure. But the statutory ceiling sets the floor for negotiation, and EPA has shown willingness to assess in the high six figures when the facts warrant it.

The recent enforcement record makes the point. The largest single TSCA penalty in 2025 was $700,000, assessed for Chemical Data Reporting (CDR) rule violations involving 334 unreported imports — a Section 8 reporting violation, not a Section 6 use violation. Three additional six-figure CDR penalties followed in the same enforcement cycle ($415,000, $393,000, $112,155). Aggregate TSCA civil penalties under the current administration ran roughly $4.3 million across 115 administrative actions through 2025. Section 8 reporting violations were the highest-yield individual category because they are documentary, provable, and visible to EPA in real time via CDX. A late or missing 8(d) submission is not the kind of compliance failure a manufacturer can defend by saying “we forgot.” EPA can see the absence directly.

The Regulatory Limbo: What EPA Has and Hasn’t Said

EPA announced reconsideration of the rule in November 2025, citing Executive Order 14219 and the “Powering the Great American Comeback Initiative.” The Agency published the proposed second extension to May 21, 2027 on March 30, 2026 at 91 FR 15582. Public comment closed April 29, 2026. As of this writing, the extension is proposed but not final.

EPA’s status page on the reporting rule states the Agency “anticipates taking appropriate action on the reporting deadline” — language that signals intent without providing a defense. There is no published enforcement discretion memo. There is no Federal Register notice tolling the deadline. The regulation on the books still says today.

This is what regulatory limbo looks like in practice. EPA has signaled it will move, but it has not moved. A plant that interprets the signal as permission to ignore the rule is making a unilateral bet that the Agency follows through before any enforcement question lands. A plant that submits the full package today does meaningful work that the modified rule may not require. A plant that does neither — neither submitting nor documenting a defensible non-submission position — is in the worst spot.

The three operational positions available today are:

Submit by today. File the inventory through CDX, claim CBI where applicable, and treat the matter as closed regardless of what EPA does with the extension. This is the most conservative posture and the most expensive in the near term.
Hold a finished package ready to submit. Complete the inventory, complete the CDX submission package, hold it for transmission, and monitor EPA’s announcements daily. If EPA issues formal enforcement discretion, the package stays held. If EPA finalizes the May 21, 2027 extension, the work is preserved for the new deadline. If neither happens within 30 days, transmit. This is the posture iSi recommends for most in-scope manufacturers.
Document an out-of-scope determination. If your applicability analysis concludes you are not in scope — small-manufacturer exemption with no Section 6 carve-out, no listed chemical in the past ten years, no byproduct or article-component pathway — write that determination down today with the underlying facts and a senior signatory. An undocumented out-of-scope assumption is not a defense if EPA later asks.

None of these positions is “wait and see.” Each is an affirmative decision with a paper trail.

The Counter-Signal: The Rule May Not End Up Where It Started

Honest practitioners read enforcement and regulatory signals in both directions. Three counter-signals deserve weight in any 8(d) decision today.

First, EPA’s reconsideration was framed explicitly under deregulatory authority. The Administrator’s public language on the parallel PFAS 8(a)(7) rule called the original requirements “crushing regulatory burdens” imposing “nearly $1 billion in implementation costs.” The most likely outcome of the 12-to-18-month reconsideration is a narrower 8(d) rule — possibly with article-importer exemptions, raised small-manufacturer thresholds, a shorter look-back, or a reduced chemical list. A plant that submits the full package today may have inventoried studies the modified rule no longer requires.

Second, the litigation challenging the December 2024 final rule was placed in abeyance in April 2025 pending settlement discussions between EPA and industry petitioners. The abeyance signals EPA’s own acknowledgment of a viable challenge to the rule’s scope. Plants timing aggressive submission may be working against a rule EPA is on the path to materially modifying.

Third, aggregate TSCA enforcement velocity is down. The ~$4.3 million total across 115 actions in 2025 is lower than peaks under prior administrations. While Section 8 reporting remains the highest-penalty individual category, the practical reading is “Section 8 is enforced when caught,” not “all 8(d) non-compliance is being actively pursued during the reconsideration window.” A plant relying on aggressive enforcement assumptions is probably reading the signal harder than the data warrants.

The honest position: the rule will likely change, but the rule still exists today. Submission preparation is still required regardless of the final form. Plants that pause work in expectation of a vacated rule are betting against EPA’s signaled 12-to-18-month reconsideration that may simply narrow the rule rather than eliminate it. The work — the inventory, the scoping determination, the CDX-ready package — is durable. It applies to today’s rule, the proposed extension, and the modified rule that lands in 2027.

If EPA Finalizes the Extension: How to Actually Use 12 Months

If the proposed May 21, 2027 deadline becomes final in the next 30 to 60 days, the 12-month window is not permission to ignore the rule. It is the period during which EPA expects to modify scope, exemptions, or both. The proper use of that window:

Months 1–3: Complete the ten-year unpublished-study inventory. This is the work most plants underestimate. Health and safety studies under the rule include environmental effects, physicochemical properties, occupational exposure, general-population exposure, consumer exposure, and environmental exposure. They sit in IH files, in product stewardship archives, in R&D notebooks, in toxicology consultancy deliverables, and — frequently — in the personal files of retiring or departed staff. Plants that wait until month 10 to start the inventory will not finish.

Months 4–6: Pressure-test the NAICS scoping determination and the small-manufacturer carve-out. This includes byproduct streams, article-component imports, and the Section 6 status of each listed chemical the facility handles. The scoping work surfaces ambiguities that require senior counsel input — better to find them in month 5 than in month 11.

Months 7–9: Build the CDX submission package and stage CBI claims. Identify which studies are submitted in full versus listed, build the CBI substantiation documentation under 40 CFR Part 703, and run a tabletop exercise of the actual CDX submission so the technical mechanics do not fail at deadline.

Months 10–12: Monitor the modified rule and adjust. EPA’s reconsideration may finalize before May 2027, in which case the inventory and submission package may be partially over-scoped — but the unused work is preserved for future Section 4 or Section 6 activity on the same chemicals.

The 12-month window is not a free pass. It is the runway to be ready regardless of what the modified rule requires.

A Note on State-Level Compliance

TSCA is federal and administered exclusively by EPA. There are no state variations in Section 8(d) reporting. The 8(d) submission satisfies the federal obligation only — it does not satisfy state Tier II inventory reporting, state air emission inventories, or state-level health-and-safety study requirements that operate in parallel.

For plants in iSi’s primary service region: Kansas KDHE Tier II is due March 1 annually under EPCRA §312, Missouri MDNR Tier II runs through MERC, Oklahoma ODEQ Tier II uses the STEERS portal, and Texas TCEQ requires both Air Emission Inventory and Tier II reporting. Plants handling listed substances like benzene, ethylbenzene, vinyl chloride, or hydrogen fluoride at quantities triggering state reporting need to track those obligations separately — completing the federal 8(d) submission does not close them.

What Inventorying Ten Years of Studies Actually Takes

Inventorying ten years of unpublished health and safety studies across six exposure categories — environmental effects, physicochemical properties, occupational exposure, general-population exposure, consumer exposure, environmental exposure — for up to 16 chemicals is exactly the kind of programmatic compliance work that does not fit on top of the safety manager’s existing month. It requires walking the IH archive, the product stewardship files, the toxicology consultancy deliverables, the R&D notebooks, and any inherited documentation from acquired sites. It requires reviewing each study for whether it meets the 8(d) definition, applying CBI analysis where appropriate, and packaging the submission through CDX. EPA’s own economic analysis estimated about $3,916 per firm just for the compliance determination — before the inventory or submission work begins.

This is the 60% of surrounding work that iSi’s COOP retainer is built to handle so the in-house EHS owner stays focused on the 40% that requires their on-site judgment. iSi’s COOP retainer starts at $15,000 per year — typically $115,000 to $180,000 less than a single fully-loaded EHS hire, with a national team in 40 states included. For a manufacturer in scope of 8(d) on multiple substances, the retainer covers the study inventory, the scoping determination across NAICS and small-manufacturer carve-outs, the CDX submission package, the CBI substantiation, and the parallel state Tier II and air inventory work that follows the same chemicals through different reporting channels. The work is the same whether EPA finalizes the extension to May 2027 or holds the May 22, 2026 statutory deadline. The retainer is the structural way to be ready either way.

The decision today — submit, hold, or document out-of-scope — is the call your EHS owner has to make this morning. The work behind the decision is what iSi handles.