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September 20, 2019

EPA Includes Unique Identifier Information on Updated TSCA Inventory

Bergeson & Campbell, P.C.

The U.S. Environmental Protection Agency (EPA) announced on September 19, 2019, that it posted the first public Toxic Substances Control Act (TSCA) Inventory to include unique identifier (UID) information. EPA states that the UID is a numerical identifier assigned to a chemical substance when EPA approves a confidential business information (CBI) claim for specific chemical identity. When EPA approves such a claim, it assigns a UID to that chemical identity; applies the UID to other information or submissions concerning the same substance; and ensures that any non-confidential information received by EPA identifies the chemical substance using the UID while the specific chemical identity of the chemical substance is protected from disclosure.

EPA notes that this is the first time that the public version of the TSCA Inventory includes both a field containing a UID for those chemical substances with approved confidentiality claims for specific chemical identity and a field containing the ten-year expiration date from the assertion of such approved claims. EPA states that the UIDs provide the public with a way to connect the specific chemical identity previously listed on the confidential portion of the TSCA Inventory with other relevant information in EPA’s holdings.

The September 2019 update to the TSCA Inventory also includes an updated commercial activity status field designating which chemical substances were “active” in U.S. commerce, based on reporting to or in any of the following:

  • 2012 and 2016 Chemical Data Reporting (CDR) cycles;
  • Notices of Commencement received since June 21, 2006;
  • Notice of Activity Form A’s received through October 5, 2018, per the TSCA Inventory Notification (Active-Inactive) rule; and
  • Notice of Activity Form B’s received to date, per the TSCA Inventory Notification (Active-Inactive) rule.

EPA designated all substances not reported as “active” as “inactive.”


EPA’s goal is to publish an up-to-date version of the TSCA Inventory about every six months. Recent versions of the TSCA Inventory have included changes other than simply including substances commenced since the last version was published. In 2018, for example, EPA published versions with a “commercial status” (CS) field. Some substances were “interim active” — that is, substances for which EPA had a notice indicating the substance would be active after the active-inactive reporting period was complete and further Form A reporting was not necessary. Other substances were blank, indicating that those substances might be inactive at the end of the reporting period. In February of this year, EPA published the first version with substances designated as inactive. Starting on August 5, 2019, companies are required to submit a Form B Notice of Activity prior to importing, manufacturing, or processing a substance designated as inactive.

With the version published today, EPA has taken another positive step in implementing its obligations under TSCA. The Inventory now includes two new fields: UI (for the unique identifier or UID) and EX (indicating the expiration date of the CBI claim). EPA continues to work through CBI identities, so only a few of the CBI substances have a UID. We expect that EPA will begin to assign UIDs to CBI substances that are newly added to the Inventory (e.g., through a Notice of Commencement submitted going forward). We also expect that EPA will assign UIDs to substances that were claimed as CBI on a Form A as EPA works through reviewing the almost 8,000 substances listed as active on the confidential portion of the Inventory.

Astute readers might note that the UI field is in both the confidential portion of the Inventory (along with PMN number, accession number, and generic name) and in the non-confidential portion of the Inventory (along with the CAS RN and CA Index Name). Some might question why the UID field is necessary in the non-confidential portion of the Inventory. The answer is because at some point, substances that had been assigned a UID will become non-confidential, and at that point, EPA must associate the UID with the CAS RN. EPA continues to work through assigning UIDs to CBI substances.

EPA must still assign UIDs to all CBI substances and also tag all data related to each of those substances with the UID for that substance. EPA will also likely add UID searching to ChemView — the Office of Pollution Prevention and Toxic’s (OPPT) portal for publishing information related to TSCA submissions. It is less clear whether EPA will add the UID and EX fields to the Substance Registry Services (SRS).

Some might view this change in the Inventory as trivial. We disagree as it is an important milestone in EPA’s implementation of the UID system as required in TSCA Section 14(g)(4). We are pleased to see EPA making progress.