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Inert Ingredients and Fees

Inert ingredient approvals are a covered application under PRIA 4, which took effect on March 8, 2019. There are 16 inert ingredient categories associated with fees and specific decision review times.

On this page:

Actions Included under the Term "New Inert Ingredients"

In general, a "new inert ingredient" under PRIA codes I001 and I004 includes:

  • A petition submitted to establish:
    • a new tolerance;
    • a new exemption from the requirement of a tolerance; or
    • a previously approved nonfood inert ingredient that is now being proposed for use as an inert ingredient in food-use pesticide products.
  • A request for approval of a new non-food use inert ingredient.

The PRIA 4 Fee Schedule Tables under the Fee Determination Decision Tree describe the ten inert categories, their PRIA 4 fees and corresponding decision review times.

Screening to Determine if Inert Ingredients Listed on the CSF are Approved for the Proposed Uses

All incoming submissions, are screened, as described in Footnote A in the 21-Day Initial Content Screen Worksheet to determine whether the inert ingredients listed on a CSF are approved for the proposed pesticidal uses or are pending before the Agency for approval for the proposed uses.

Finding Inert Ingredients Approved for Food Use Products

Our InertFinder allows users to determine whether an ingredient has been approved for food and/or non food use and outlines any use limitations. Inert ingredients requiring data compensation are also identified in the InertFinder.

In general, the only inert ingredients approved for use in pesticide products applied to food are those that have either a tolerance or an exemption from the requirement of a tolerance in the Code of Federal Regulations (CFR), 40 CFR part 180 (the majority are found in sections 180.910 - 960).

The most up-to-date tolerances and tolerance exemptions are found in the electronic CFR (e-CFR). The InertFinder* includes links to the appropriate CFR citation for each chemical name and CAS Reg. No. Note that many food-use inert ingredients have use limitations and restrictions.

*DISCLAIMER: InertFinder is intended solely to enhance public access to information related to the approval status of substances used as inert ingredients in pesticide products. The user should be aware that while an effort is made to ensure that the information in InertFinder is regularly updated and accurate, there are no express or implied guarantees. The Federal Register and the Code of Federal Regulations remain the official source for regulatory information related to the use of inert ingredients in pesticide products used on food.

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Ways to Find Approved Inert Ingredients without Using the Chemical Name

There are several ways to look up chemicals other than by using the chemical name. These are described below.

CAS Number

You may be able to find the chemical by its CAS Registry number (commonly noted as CASRN or CAS). A CAS Number is a unique numeric identifier assigned to a particular chemical substance. CAS numbers are managed and assigned by the American Chemical Society's Chemical Abstracts Service.Exit

Some chemicals are known by different names or synonyms; therefore it may be necessary to expand your search criteria to include those different names. To search for synonyms, go to EPA's Substance Registry Services (SRS) and search by the same methods listed below under Synonym.

An Important Note about CAS Numbers and the e-CFR

The e-CFR includes many of the inert ingredient CAS numbers, but not all. Some CAS numbers are listed as part of a general chemical descriptor and do not appear in the CFR. Check the InertFinder if you believe that your CAS number falls under one of the chemical descriptors listed in the CFR.


The chemical you are looking for may be listed by one of its synonyms. Often the name of a particular chemical is quite straightforward (e.g., sand) but other times a given chemical appears to go by two or three entirely different names (e.g., calcium stearate and octadecanoic acid, calcium salt are two different names for the same chemical). These different names are called synonyms.

To see if your chemical has a synonym:

EPA's Substance Registry Services (SRS)

  • Go to EPA's Substance Registry Services (SRS).
  • Choose the Search & Retrieve Tab.
  • Use Substance Search to Search by:
    • Synonym (Enter a CAS name, Biological name, EPA Registry Name or other Synonym. Select the “Exact Match” radio button).
    • Substance Identifier (Enter a CAS Number, TSN, EPA Identifier, Internal Tracking Number, or Alternate Identifier.).
    • Substance Type (Use this to narrow your search by identifying the substance type from the drop down menu).
  • Choose the Return Type.
  • Click Search (Select this button to run your search request. The chemical's different names (synonyms) should appear, along with its CAS number.).

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Inerts that are not in the InertFinder, the e-CFR or the Web

If the chemical does not appear be in 40 CFR 180, subpart D, it is possible that the chemical you are looking for is not an inert ingredient that EPA has approved for use in pesticide products. Alternatively, the chemical may be included in a group exemption

If you need help, contact the Inert Ingredient Assessment Branch (IIAB) ( In your e-mail please try to be as specific as possible as to what chemical you are trying to locate.

Information on Other Pending Applications

Due to concerns about confidential business information, the Agency, in general, cannot provide information regarding the status of a pending inert ingredient application. Information on whether an inert ingredient application is currently pending with the Agency and for what uses should come from the inert ingredient applicant.

In cases where another covered application, such as a product registration application, intends to associate with and depend upon an already pending application for an inert ingredient approval, the applicant must identify the pending inert ingredient action in its application. To identify the inert, the applicant must provide the:

  • inert approval tracking number and/or petition number assigned by the Agency;
  • name of the inert ingredient(s) that is pending (include the CAS number if appropriate); and
  • name of applicant who has submitted the inert ingredient’s applicant’s name.

This information can be requested from the pending inert ingredient petition.

The Agency will not provide information to the applicant of the dependent covered application regarding the status of the pending inert ingredient approval action beyond information that must be shared to adjust the decision review time due date for the dependent application at the start of the review.

Further Guidance on Inert Ingredient Applications

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