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NAFTA Guidance on Data Requirements for Pesticide Import Tolerances: Questions & Answers

On April 5, 2006, EPA announced in the Federal Register the availability of a guidance document describing the data requirements for establishing pesticide import tolerances in Canada and the United States. Mexico is not participating in the program at this time. A proposed version of this document was released for public comment on April 26, 2003. The revised NAFTA guidance document is available on EPA’s website and in the docket at, docket ID EPA-HQ-OPP-2002-0281.

Answers to questions the public may have about the NAFTA guidance document are provided below.

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What is an Import Tolerance?

A U.S. tolerance (called a Maximum Residue Limit or MRL in Canada and many other countries) is the maximum residue level of a pesticide permitted in or on food or feed grown in the United States or imported into the United States from other countries. EPA usually establishes a tolerance, or an exemption from the requirement of a tolerance, when it registers a pesticide for use on a food or feed commodity in the United States. When no U.S. registration exists, interested persons may submit a petition requesting that EPA establish an import tolerance (or tolerance exemption) for a pesticide residue on a food or feed commodity, which will allow the food or feed treated with the pesticide in foreign countries to be lawfully imported into the United States. The term, “import tolerance,” then, is used as a convenience to refer to a tolerance that exists in the United States for which there is no accompanying U.S. registration, but that meets U.S. food safety standards.

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Are Import Tolerances Based on Different Safety Standards Than Regular U.S. Tolerances?

There is no statutory or regulatory distinction between an import tolerance and any other tolerance established by EPA. Both must meet all current statutory requirements, including the safety standard (“reasonable certainty of no harm”) for pesticide residues in food, set forth in Section 408 of the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA).

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What is the Legal Authority for Setting and Enforcing Tolerances in the United States?

EPA regulates pesticides under two major statutes, the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) and the FFDCA. FIFRA requires that pesticides be registered or licensed by EPA before they may be sold or distributed for use in the United States. Section 408 of the FFDCA authorizes EPA to establish, modify, or maintain tolerances or tolerance exemptions for pesticide residues in or on food. Any food with pesticide residues not covered by a tolerance or tolerance exemption, and any food with residues in excess of the tolerance, may be subject to regulatory action, including seizure, by the U.S. government. Pesticide tolerances and exemptions are enforced by the U.S. Food and Drug Administration (for most foods), the U.S. Department of Agriculture (for meat, poultry, and some egg products), and the individual states.

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Why are Import Tolerances Necessary?

Food may not be lawfully sold in the United States or imported into the United States from other countries if the food contains detectable pesticide residues above the level permitted by a tolerance, or if the food contains residues at any level if no tolerance or tolerance exemption has been established.

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What Data are Needed to Obtain an Import Tolerance, and How do the Data Requirements Differ From Those for a Regular Tolerance?

Import tolerances generally require the same types of data as are needed to establish tolerances associated with U.S. registrations, including product chemistry, residue chemistry, and toxicology data, as well as data representative of actual growing conditions. EPA needs these data to assess the potential dietary risk and make the required safety finding. The Agency does not require worker exposure, residential exposure, or environmental fate and effects data to establish import tolerances since these data are not needed to assess dietary risk, although these data would be required if the pesticide were to be registered for use in the United States.

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What is the Purpose of the NAFTA Import Tolerance Guidance Document?

The NAFTA guidance document details the product chemistry, residue chemistry, and toxicology data requirements that meet NAFTA standards for the establishment of import tolerances or maximum residue levels (MRLs) in Canada and the United States. This common approach to establishing import tolerances is expected to promote trade between North America and the rest of the world.

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Does the NAFTA Import Tolerance Guidance Reduce or Remove the Requirements for Obtaining an Import Tolerance in the United States, or for Obtaining a Separate MRL in Canada or Mexico?

No, the guidance document does not change U.S. data requirements for obtaining import tolerances in this country. Also, tolerance petitioners still must submit separate import tolerance/MRL petitions to the United States and Canada and must adhere to each country’s specific formatting and other requirements. The common set of data requirements presented in the guidance document, however, typically will result in a reduced data set, as well as a more efficient and cost effective review process for obtaining import tolerances in North America. The United States and Canada encourage the concurrent submission of petitions so that joint review projects can be initiated. Joint review of petitions will help harmonize the setting of import tolerances/MRLs in the United States and Canada, promoting free trade within North America.

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What are Joint Review Projects, and How do They Help Promote Trade?

The United States and Canada are conducting joint reviews of certain selected pesticides, the results of which apply to both countries. For example, an acceptable joint Canadian-U.S. toxicology data review would satisfy the data requirements for both countries. Reviews of studies conducted under this agreement also would be applicable to import tolerances in both countries.

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If a Codex MRL has been Established, Will Fewer Studies be Needed to Support an Import Tolerance/MRL in the NAFTA Countries?

Codex is a joint Food and Agriculture Organization (FAO)/World Health Organization (WHO) food standards program which develops internationally agreed upon food standards, including Maximum Residue Limits (MRLs). If a Codex MRL has been established, the United States and Canada may conduct a more limited review of the residue chemistry data supporting a proposed import tolerance/MRL, under certain circumstances. The United States and Canada are more likely to adopt import tolerances/MRLs similar to Codex MRLs if MRLs for the pesticide are already established on other commodities with a contemporary, robust database. Standard data and review requirements would be applied where exposure and/or risk to any subpopulation from the pesticide is high. Mexico accepts Codex MRLs on commodities for domestic consumption. A detailed description of how the United States may consider Codex MRLs when establishing import tolerances can be found in Unit VIII of the EPA document, Guidance on Pesticide Import Tolerances and Residue Data for Imported Food, published in the Federal Register on June 1, 2000 (65 FR 35069).

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Are New Studies Required to Fulfill the New NAFTA Import Tolerance Data Requirements?

The import tolerance/MRL petitioner may not need to conduct new studies to fulfill the NAFTA data requirements. Interested parties may support a new import tolerance/MRL in the United States and Canada with studies developed for a registration in another country and/or for a Codex MRL, provided that the petitioner is able to demonstrate to each country the applicability of the studies to the requirements in the guidance document. The petitioner or interested party is encouraged to consult with the United States and Canada before submitting existing studies. All studies must be formatted in accordance with the requirements of the country to which the package is being submitted. The United States and Canada strongly recommend that petitioners attach a copy of the study evaluation by the registering country or by Codex to the study report as an appendix.

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What are the Most Important Studies Required by the NAFTA Countries to Support New Import Tolerances/MRLs?

The most significant data required for establishing new import tolerances/MRLs are crop field trials. In addition, for pesticides not already registered, toxicology data requirements also are significant.

Field trials are conducted to determine the maximum residue that may be expected in or on a raw agricultural commodity as a result of the legal use of a pesticide. The number of field trials recommended in the NAFTA guidance document was derived from the number required for a tolerance associated with a U.S. registration and also takes into consideration the maximum consumption of the commodity as a percentage of the United States or Canadian diet, and the maximum relative amount imported into the United States or Canada from outside of North America. Field trials generally will need to be conducted in all countries whose exports comprise at least 5% of the total amount of a specific commodity imported into either of the countries where a tolerance is being sought. For complete information on field trials and other data requirements, please see the NAFTA guidance document.

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What are Zone Maps and How are They Used?

Zone maps divide North America into regions where growing conditions are similar. Thus, field trials conducted within the same zone are considered interchangeable. The United States and Canada use zone maps to determine where field trials should be conducted for tolerances/MRLs associated with domestic pesticide registrations.

In the future, if other countries develop zone maps, and crop cultural practices, climatic conditions, and pesticide use patterns within the mapped foreign regions are demonstrated to be substantially similar to those in North American regions, then the United States and Canada may consider substituting North American data with data from corresponding regions within other countries.

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When an Import Tolerance is Established in One NAFTA Country, Does it Automatically Apply in All Three NAFTA Countries?

No, however, the NAFTA countries will attempt to harmonize tolerances/MRLs with each other to the maximum extent possible, consistent with the laws of each country and their obligations under World Trade Organization agreements. Our mutual objective is to work toward greater harmonization in international fora.

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Does the New NAFTA Import Tolerance Guidance Change the Food Safety Protections Afforded U.S. Consumers?

U.S. consumers will continue to enjoy the same excellent food quality and safety protections they have always enjoyed, under the new NAFTA import tolerance guidance.

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