United Nations Chemical Inventory Information

The US operates the Toxic Substances Control Act (TSCA) Inventory, which is managed by the Environmental Protection Agency (EPA). As of February 2024, the TSCA Inventory contains 86,770 substances. This includes 70689 substances with CAS numbers (non-confidential) and 16081 classified as confidential. Of these 42,377 are currently active in U.S. commerce.  

The initial inclusion in the chemical inventory was governed by a cut-off criterion for substances in commerce before 1979 to distinguish between existing and new chemicals. Manufacturers and importers must comply with Pre-Manufacture Notification (PMN) requirements for new chemicals. Regular updates ensure that the inventory reflects the evolving landscape of industrial chemicals.  

The TSCA Inventory also includes regulatory flags that indicate whether substances are subject to specific EPA rules, exemptions, or restrictions. For example:  

• 5E, 5F, and 12C flags identify substances subject to Section 5(e) orders, Section 5(f) rules, and Section 12(c) export prohibitions, respectively. 

• R and S flags identity substances associated with Section 6 risk management rules and Significant New Use Rules (SNURs), while SP indicates proposed SNURs. 

• XU indicates an exemption from reporting under the Chemical Data Reporting Rule. 

• PE1, PE2, and PE3 flags indicate polymer exemptions under the 1995 Polymer Exemption Rule, and Y1/Y2 corresponds to the 1984 Polymer Exemption Rule for low-concern reactants. 

• PMN marks commenced Premanufacture Notification substances. 

In addition to regulatory flags, substances on the TSCA Inventory are classified based on their listing status and regulatory requirements. These classifications determine obligations for manufacturing, importing, and commercial use. 

• Listed Substances: Allowed to be manufactured, imported, and used without a PMN, provided they comply with TSCA requirements such as reporting, labelling, and risk management obligations. 

• Unlisted Substances: Classified as new chemicals that require submission of a PMN to EPA for evaluation of potential risks to human health or the environment prior to approval for use. 

• Active Substances: These can be manufactured, imported, or processed without additional notifications, whereas inactive substances require a 90-day advance notification (NOA-B) before their commercial use. The inventory is divided into public and confidential sections, with 18,416 substances classified as confidential and accessible only through a specific request process. 

In the United States, the TSCA Inventory, is divided into public and confidential sections. Confidential chemicals are protected under the Confidential Business Information (CBI) provisions, which require companies to provide justification at the time of notification. EPA periodically reviews these claims to ensure their validity and transfers improperly claimed confidential substances to the public inventory. This approach balances transparency with the protection of trade secrets and ensures that public safety is not compromised.