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Information provided for informational purposes only

Note: This information is provided for reference purposes only. Although the information provided here was accurate and current when first created, it is now outdated.

Status Report for PPDC:

"Inert" or "Other" Ingredients in Pesticide Products

EPA's 1987 Policy for Inerts
Evaluation of the Potential Imact of Inert Ingredients
Confidentiality of Pesticide Data and the Freedom of Information Act
Enhancing Public Access to Pesticide Information


The Office of Pesticide Programs (OPP) evaluates the safety of pesticides to humans and the environment through the registration and reregistration processes. OPP's Registration Division (RD) is primarily responsible for the implementation of the inert ingredient regulatory program. Inert ingredient review activities compete with resources that are also used to conduct other registration-related activities such as the review of new active ingredients, reduced-risk pesticides, new uses of existing products, minor use petitions and emergency exemption requests. While resources dedicated specifically to the review of inert ingredients have increased slightly over the last five years, they continue to be a relatively small portion of the overall program allocation. Any increase in resources for inert ingredient review activities occurs at the expense of diminishing resources for other pesticide program activities. Given this set of circumstances, it becomes particularly important for OPP to utilize its limited inert ingredient review resources in the most efficient manner. This paper describes the regulation and evaluation of inert ingredients in pesticide products, identifies the Environmental Protection Agency's (EPA) current policy, highlights program accomplishments and identifies significant issues.

A. Ingredients in Pesticide Products

Pesticide products contain "active" and "inert" ingredients. The terms "active ingredient" and "inert ingredient" are defined under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). An active ingredient is one that prevents, destroys, repels or mitigates a pest, or is a plant regulator, defoliant, desiccant or nitrogen stabilizer. By law, the active ingredient must be identified by name on the label together with its percentage by weight. The statute defines the term "inert ingredient" merely as an ingredient which is not active. The law does not require individual inert ingredients to be identified by name and percentage on the label, but the total percentage of all inert ingredients must be declared.

Historically, EPA has considered a substance to be "active" based largely on the label claim of the pesticide product. For example, a chemical that is intended to control a target pest, such as an insect, would be considered an active ingredient in an insecticide formulation. However, when the same chemical is used in a herbicide product, the chemical might perform the function of a solvent and would therefore be considered an inert ingredient in that particular formulation.

In September 1997, EPA issued Pesticide Regulation Notice 97-6 requesting registrants of pesticide products to voluntarily substitute the term "other ingredients" in lieu of the term "inert ingredients" on the label. EPA made this change after listening to comments from the public, and learning the results of a consumer survey on the use of household pesticides which indicated that many consumers are misled by the term "inert," believing it to mean "harmless." Since neither the federal law nor the regulations define the term "inert ingredients" on the basis of risk to humans, non-target species, or the environment, it should not be assumed that all inert ingredients are non-toxic. For convenience and consistency, the term"inert" will be used in this paper.

B. Historical Background: Regulation of Inert Ingredients Before 1987

Prior to the establishment of the EPA, the Department of Agriculture (USDA) was responsible for the registration of pesticides under FIFRA. The Food and Drug Administration (FDA) was responsible for establishing tolerances or safe levels of pesticide residues in raw agricultural commodities and food.

In 1961, FDA published a Federal Register notice (26 FR 10640; November 14, 1961) stating that USDA had determined that each component of registered pesticide products, including the inert ingredients, were pesticide chemicals. This determination meant that a tolerance (maximum legal levels for pesticide residues in raw agricultural commodities) or an exemption from the requirement of a tolerance had to be established for inert ingredients as required by the Federal Food, Drug, and Cosmetic Act (FFDCA).

By 1969, the FDA had established a policy regarding data requirements and review procedures for inert ingredients (34 FR 6041; April 3, 1969). This notice set forth general toxicity data requirements and stated that residue data requirements would depend on the toxicity of the chemical. The policy also allowed a simplified review process if FDA concluded that the inert ingredient was generally recognized as safe for the stated purpose. Likewise, the process to exempt an inert from the tolerance requirement generally occurred through an informal request procedure, rather than the formal petition process required for active ingredients.

In 1970, the authority to register a pesticide and to establish tolerances or exemptions to a tolerance for pesticide chemicals was transferred to EPA. However, since most of the data requirements and regulatory activities under FIFRA focused on the active ingredient, EPA exerted little regulatory control over inert ingredients. By 1984, there were two exceptions to this general policy. First, acute toxicity testing on the pesticide formulation, which generally includes both active and other ingredients, was routinely required for registration of end-use products. End-use products are the form of pesticide product which the public is most likely to purchase for use. Acute toxicity tests are used to determine short term effects. Second, certain labeling requirements for hazardous inert ingredients were imposed (49 FR 37980; September 26, 1984).


>In 1987, EPA announced a comprehensive policy to "reduce the potential for adverse effects from the use of pesticide products containing toxic inert ingredients" (52 FR 13305; April 22, 1987). The policy also established criteria for the types of information needed to evaluate the impacts to human health and the environment from the use of the inert ingredients in pesticide formulations. The Agency concluded that some inert ingredients had potentially significant long-term health and environmental hazards associated with their use in pesticide products. The policy emphasis on the long-term health and environmental effects of inert ingredients requires pesticide registrants to specifically consider these effects when developing new pesticide formulations.

The 1987 notice and the current Agency policy establish data requirements for new inert ingredients and categorize all inert ingredients into four categories (or lists), including:

List 1

Considered to be of "toxicological concern," 57 chemicals were originally placed on List 1 because they demonstrated the potential to cause either: cancer, nerve damage, adverse developmental and reproductive effects, or adverse ecological effects. All List 1 inert ingredients are required to be disclosed on the product label. OPP also issued Data Call-In notices (DCIs) for these chemicals which required registrants to submit additional data. The data requested were equivalent to the data required for a new active ingredient to demonstrate that these chemicals can be safely used in pesticide formulations. There are now only eight List 1 inert ingredients currently in use.

List 2

There are 52 chemicals classified as List 2 inerts. Ingredients on this list are classified as potentially toxic with a high priority for testing. Agency review indicated that many of these chemicals had structural similarities to List 1 inert ingredients, or there were data suggesting a degree of toxicity or hazard. The Agency continues to evaluate the available data to determine whether a sufficient basis exists to allow these substances to be reclassified to List 1 or List 4.

List 3

List 3 inerts includes chemicals of unknown toxicity. There are about 1700 chemicals on this list. OPP is currently developing toxicological and ecological assessments for these inerts.

List 4

This list includes 430 chemicals of minimal concern. In 1989, this list was further divided into List 4A, minimal risk inerts, and List 4B, inerts for which the Agency had sufficient information to conclude that their current use patterns in pesticide products would not adversely affect public health and the environment.


A. Managing the Process

When OPP reviews the registration of a pesticide product, the information submitted on the pesticide formulation is evaluated to verify that the inert ingredients in the pesticide product are deemed acceptable for the proposed use. Inert ingredients proposed for use in pesticide formulations applied to food must also have a tolerance or exemption from the requirement of a tolerance. OPP received 25 petitions for the establishment of a tolerance or tolerance exemption for inert ingredients in fiscal year (FY)1998. The number of final decisions on tolerance/tolerance exemption petitions for inert ingredients has increased. Fifteen final decisions were made in FY 1998 while no decisions were made in FY 1997. However, there are currently some 77 inert ingredient tolerance/tolerance exemption petitions for which the Agency has not rendered a final decision. In FY 1998, OPP also reviewed and approved a record 94 new nonfood use inert ingredients.

B. Review of "New" Uses Inert Ingredients

Some inert ingredients are "new," meaning the substance has not been identified as being used in an approved pesticide formulation. OPP requires that supporting data be submitted before a new inert ingredient can be considered for approval. The data required are a subset of the kind of data typically required for active ingredients under 40 CFR Part 158. These data requirements include residue chemistry, product chemistry, toxicology, ecotoxicology and environmental fate studies. EPA can waive some of these data requirements, if the applicant can show that the proposed new use pattern of the inert ingredient will result in little or virtually no exposure. EPA may also require information addressing dietary, groundwater or applicator exposure, as appropriate. EPA applies these same data requirements to new inert ingredient tolerance exemption petitions, petitions to amend existing inert ingredients tolerance exemptions, and requests for new nonfood use inerts.

C. Evaluation of Existing Inert Ingredients

The Agency is also evaluating existing inert ingredients. This effort is primarily focused on examining information available on List 2 and 3 inert ingredients to support decisions to reclassify these ingredients as either List 1 or List 4 inert ingredients.

D. Review of Other Scientific Data

Review of scientific literature and other data bases that contain information related to pesticides can, at times, provide relevant information for pesticide regulation. While data from these sources do not always meet EPA's strict standards (e.g., Good Laboratory Practices, evaluation criteria uses risk based standards) some do and are directly used for regulatory purposes when appropriate. Sometimes these sources are helpful because they direct the need for additional data when they suggest a potential concern with a pesticide ingredient. At other times, these sources provide supporting evidence for a decision that is based primarily on data meeting Agency standards.

In the last several years, OPP has re-analyzed considerable existing data on List 2 and 3 inerts and obtained some data through the of review of scientific literature and other data bases. The Structure Activity Team (SAT) of the Office of Pollution, Prevention, and Toxics conducted a review of available data on all 1700 List 3 inert ingredients to predict the effects of these chemicals on human health and the environment. The SAT review uses both existing information and predictions of a substance's likely toxicity and environmental effects. The SAT effort is being incorporated with existing OPP analysis and will be reviewed to determine if any reclassification for listing can be made. OPP has also been reviewing the data used for listing and delisting chemicals on EPA's Toxic Release Inventory (TRI). Like the SAT reviews, TRI reviews will be used to supplement the existing OPP data base. Because of these types of reviews, the four lists have been undergoing a variety of changes since their inception. Some of the changes in the last 5 years include:

1. Reclassification of List 4 Inert Ingredients

In 1994, List 4A, ingredients of minimal risk, was amended to include all commonly consumed foods used as inerts (59 FR 49400; September 28, 1994).

2. Reclassification of List 3 Inert Ingredients to List 4 Chemicals

In 1995, 146 inert ingredients, previously classified on List 3, were moved to List 4B (60 FR 35396; July 7, 1995). The moves were based on SAT reviews showing the substances were of low concern to human health and posed minimal environmental effects and were already approved for use by the FDA as direct food additives, or were low risk polymers that met the criteria established by the polymer exemption rule at 40 CFR 723.250.

3. Chemicals Removed from the Inert List

In 1998, the Agency removed certain chemicals from the inert list because they had not been used in pesticide formulations for at least two years (63 FR 34384; June 28, 1998). Some of the List 1 inert ingredients removed were no longer used as a direct result of the DCI's issued under FIFRA. A total of 251 chemicals were removed (32 List 1, 12 List 2, and 207 List 3).


A. Background: Requirements of the Food Quality Protection Act

The Food Quality Protection Act (FQPA) of 1996 requires reassessment of all food use inert ingredients which have tolerances or exemptions from the requirement of a tolerance to ensure that they meet the safety standards in the new law. In the past, consideration of tolerances or exemptions from a tolerance for inert ingredients were based solely on risk associated with their use in pesticide products. As of August 3, 1996, new tolerances are to be calculated for food use inert ingredients by assessing the aggregate exposure of the pesticide chemical residue including all dietary and non-dietary exposures resulting from their use in pesticide formulations, as well as exposures from non-pesticidal uses. The new tolerance reassessment process must now also focus explicitly on exposures and risks to infants and children, and possible disruptive endocrine effects. In addition to the new health standards, FQPA mandates data compensation and exclusive use rights for inert data submitters who submit data in support of a tolerance or exemptions to a tolerance. FQPA also directs EPA to establish a 15-year cycle review program to re-evaluate all registered pesticide products. This re-evaluation will include review of the pesticide formulations including any inert ingredients in the formulation.

B. Establishing a Streamlined FQPA Process for Reviewing Inert Ingredients

The vast majority of OPP resources for the review of inert ingredients are allocated into two specific areas, the review of new inert ingredients (both food use and non food use) and the evaluation of existing inert ingredients. OPP's current practice is to incorporate selected new inert ingredient actions (and, on rare occasions, existing inert ingredient actions) into its registration priority system. However, most of the criteria for establishing registration priorities are specific to active ingredients (e.g., methyl bromide substitutes or alternatives to organophosphate pesticides). Other methods for establishing registration priorities, such as reduced risk claims for new active ingredients, have very limited utility for new inert ingredients. Establishing priorities in the area of existing inert ingredients has proven to be even more problematic given the large numbers of existing inert ingredients for which definitive risk assessments are lacking.

1. Prioritization Scheme is needed

Any prioritization scheme for the review of inerts must also be allied with all of the other registration priorities. For example, in the FY 1999 Registration Division work plan, RD projects about 90 registration decisions for new chemicals (active ingredient), new uses for already-registered active ingredients, and inert ingredients combined. Of the 90 expected decisions, seven relate to inert ingredients (five new inerts and two existing inerts). The seven inert ingredient decisions are included based solely on the length of time the inert ingredient submission had been awaiting review and their databases are essentially complete. What is most notably absent from the current prioritization scheme for inert ingredients is some form of incentive to offer higher priority to those inert ingredient actions that would comport with stated Agency objectives such as reducing the overall risks from the use of inert ingredients in pesticide formulations and encouraging the use of the least toxic inert ingredients available.

C. Creation of Data Compensation and Exclusive Use Rights Section under 408(i)

As part of the Food Quality Protection Act (FQPA) of 1996, Congress amended section 408(i) of the Federal Food, Drug, and Cosmetic Act (FFDCA) to address exclusive use treatment and compensation for data submitted to EPA in support of a tolerance or an exemption to a tolerance under FFDCA to the "same extent provided" by section 3 of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). The pertinent part of the statutory language is provided in attachment 1.

1. Preliminary Options for Implementing Section 408(i)

EPA believes the new section 408(i) of FFDCA may provide the Agency with the flexibility to develop one or more possible implementation schemes including:

Option 1

One reading of section 408(i) would entitle data compensation and exclusive use rights (data rights) only to those persons who submit data in support of tolerances or exemptions from tolerances that also meet all the conditions necessary to obtain such rights as set forth in section 3 of FIFRA. Therefore, under this option, data rights would only be granted to those persons who submit data who qualify as a pesticide registrant applicant submitting data for a current registration or reregistration action.

Option 2

This reading of section 408(I), as in option 1, would entitle data compensation and exclusive use rights to those persons who submit data in support of tolerances or exemptions from tolerances that also meet all the conditions necessary to obtain such rights as set forth in section 3 of FIFRA. The data submitted would have to be in support of a current registration or reregistration action. However, the data submitter would not have to qualify as a pesticide registration applicant or pesticide registrant.

Option 3

This reading of section 408(i) would entitle data compensation and exclusive use rights to persons who submit data and who would otherwise qualify for data rights under both options 1 and 2 above. However, this option would also extend rights to data submitters without regard to whether the data submitted relates to any current registration or reregistration action.


A. The Freedom Of Information Act Process

The Freedom of Information Act (FOIA) allows the public to request copies of records in the possession of federal agencies. EPA is required to provide the fullest possible disclosure of information to the public unless the information falls into one of the exemptions under the FOIA (e.g., personal privacy, confidential business information, trade secrets, sensitive information, etc.). Most of the Office of Pesticide Programs's (OPP) records not specifically prepared for routine public distribution fall within the scope of the FOIA. The types of pesticide program records handled under FOIA include, but are not limited to, FIFRA health and safety data, internal data reviews or memoranda, and administrative files for registered products. Like the substantiation process, FOIA regulations provide a comprehensive series of procedures governing public access to information. If a FOIA request involves asserted CBI claims, the timeliness of the Agency's response is dependent upon the substantiation process.

A formula or "recipe" for each pesticide product is submitted to the Agency as part of the registration requirements. The formula information submitted includes the identity and percentage of the individual active and inert ingredients in the formula. The identity of inert ingredients is frequently asserted as confidential business information (CBI) by pesticide registrants. The current Agency process to substantiate an asserted CBI claim requires that each claim be evaluated on a case by case basis. This process can be slow. By law, EPA is prohibited from disclosing CBI to the public. However, the Agency may disclose CBI in limited circumstances, such as when necessary to treat illness or injury, or to prevent imminent harm to persons, property or the environment. Even then, release of the information must often be limited to certain "qualified persons" such as medical personnel, who may not disseminate the information more broadly. Agency regulations related to CBI and public information are found in 40 CFR part 2.

B. Assertion of CBI Claims

Prior to releasing business information to the public, the Agency must determine whether the information is subject to a confidentiality claim. If there is no indication whether the submitter claims the information as CBI, EPA must inquire whether the submitter wishes to assert a claim if either of two circumstances apply: (1) the information was submitted before October 1, 1976, or (2) the information is such that the submitter might be expected to object to its release (generally, when there is a history of CBI claims for this type of information e.g., inert ingredients). However, the Agency need not make such an inquiry if the submitter has received prior notice that information not claimed as confidential may be disclosed without further notice.

C. Substantiation of CBI Claims

Once the Agency has established that information is claimed as CBI, EPA confidentiality regulations impose a series of procedures governing whether and how such information may be disclosed. For pesticide registrants, part of this procedure means responding to an Agency letter requesting that the CBI claim be substantiated. The Agency letter seeks responses to such questions as to whether the information has been disclosed to the public, what measures the submitter has taken to ensure non-disclosure of the information, and whether disclosure of the information is likely to cause substantial competitive harm. Normally, the submitter has 15 working days after the receipt of the Agency letter to respond. However, the submitter can request an extension.

D. EPA Determines Whether Information Is Entitled to Confidential Treatment

After the submitter has responded to the Agency's substantiation letter, EPA makes a final administrative determination whether the information is entitled to confidential treatment. Once a determination is made, notice of the Agency's final action is furnished to the submitter. If the Agency determines the information not to be entitled to confidential treatment, the final notice states that EPA will make the information publicly available within 31 days after receipt of the final action. Final Agency actions may be subject to injunctive relief and full judicial review.

E. Request for Disclosure of Inert Information

OPP processes approximately 1800 FOIA requests annually. About 1% of these requests seek information about the identities of pesticide product inert ingredients. These requests can take as little as six weeks to complete. However, some requests seek disclosure on thousands of products involving hundreds of registrants and can take several years to complete. Since 1996, using the substantiation process, OPP has disclosed the identity of some or all of the inert ingredients in over 160 products. Currently, over 20 appeal requests seeking disclosure for inert ingredients are awaiting final confidentiality determinations at EPA.

F. Redaction of Information and Streamlining the Process for Substantiation

OPP is actively planning for increased reliance on electronic submission of registrant transactions with the Agency to lay the ground work for other electronic commerce opportunities in the future. However, most of the Agency's current activities for electronic information processing are not focused on redaction of information for FOIA activities or streamlining the substantiation process.

G. Petitions Regarding Inert Disclosure

In 1998, the Northwest Coalition for Alternatives to Pesticides (NCAP) and the Attorneys General of New York, Alaska, Connecticut, Guam, Massachusetts, Minnesota, New Hampshire and Wisconsin and the Massachusetts Executive Office of Environmental Affairs, filed petitions with the Agency requesting changes to EPA's labeling regulations to require full disclosure of inert ingredient identities on the product label (see attachments 2 and 3). EPA has also received a letter signed by the American Crop Protection Association, the Chemical Manufacturers Association, the Chemical Producers and Distributors Association, the Chemical Specialties Manufacturers Association, the International Sanitary Supply Association, and Responsible Industry for a Sound Environment asserting arguments against actions sought by the petition and a request that EPA not grant the petition requests (see attachment 4). EPA is considering all requests submitted.


In the past year, EPA dedicated resources to make information about inert ingredients available via the INTERNET.

- OPP created a web site, Inert Ingredients in Pesticide Products, www.epa.gov/opprd001/inerts, which allows the user to search the list of approximately 2500 inerts by CAS number, chemical name, or inert category listing. The site also provides users access to the Federal Register and Pesticide Registration notices applicable to inert ingredients.

-OPP created the web site, Read the Label First, www.epa.gov/pesticides/label.  EPA has created a label with pop-up text that explains the basic statements found on pesticide product labels, including inert or other ingredients.

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