Maximum Residue Limits (Tolerances) of Pesticides on Agricultural Food Commodities

Residue tolerances are established for all pesticides registered on agricultural commodities. For synthetic pesticides and materials that are produced by fermentation and which are concentrated and/or reformulated, maximum residue limits (i.e., tolerances) have been established by national (country-based) and international regulatory agencies. In the United States, the Environmental Protection Agency (EPA), along with the Food and Drug Administration (FDA) are involved in establishing limits on agricultural food commodities for all registered products including those designated as “exempt” (an EPA designation) or “generally regarded as safe” or GRAS (an FDA designation). Use limits are set for the latter materials, whereas all other materials must have analytical procedures available to measure chemical residues on the commodity. Internationally, the United Nations World Health Organization (WHO) and Food and Agricultural Organization (FAO) created the CODEX Alimentarius Commission to develop food standards, guidelines, and practice codes.

The main goal of national and international agencies is to protect the health of consumers, ensure fair practices in food trade, and promote coordination of food standards. The process of registering a pesticide on a food commodity is rigorous and requires numerous evaluations ranging from toxicity to environmental persistence and chemical fate studies. The limits of a pesticide residue on each commodity are established as a maximum residue level or limit (MRL) which is considered an absolute minimal risk to the consumer. Most countries use the term MRL, but U.S. regulations refer instead to "tolerances". Both terms indicate the amount of pesticide residue that is permitted to remain on a plant commodity. Generally, the MRL level is two or more times higher than what is expected for a residue under labeled pesticide usage. The CODEX Alimentarius as part the World Health Organization (WHO) and the Food and Agriculture Organization (FAO) provides users with a list of MRL tolerances by commodity, pesticide, or functional class of the database at http://www.codexalimentarius.net/pestres/data/index.html. In the United States, the website for viewing Global MRLs is https://www.globalmrl.com and is provided by Bryant Christie Inc. Registered pesticide MRLs for many markets around the world may be searched by commodity, pesticide, and market. Global MRLs is designed for users in the United States. It provides MRL information from a U.S. viewpoint. This means that other countries' MRLs are only included if there is a U.S. MRL established for the commodity/active ingredient combination. This also means that the active ingredient and commodity menus available to search are limited to those listed in the U.S. Code of Federal Regulations (CFR) Title 40 CFR 180 Subpart C for pesticide specific tolerances.

Three rules of the Global MRL Database should be noted: 

1. U.S. general, Section 18, regional, and time-limited pesticide MRLs for raw commodities that are currently in force for U.S. Environmental Protection Agency (EPA) registered active ingredients as listed in the U.S. Code of Federal Regulations (CFR) Title 40 CFR 180 Subpart C, and corresponding in force MRLs for other countries.
2. U.S. tolerances specifically designated in the CFR as import tolerances or without current U.S. registrations
3. Processed commodity MRLs

The Global MRL Database exclusively reflects maximum residue levels that have been established on a permanent basis under domestic US legislation according to the US CFR. The following types of MRLs are not included in the database:

• Other markets' MRLs in cases where there is no U.S. MRL established
• U.S. tolerances for indirect or inadvertent pesticide residues
• Pending and proposed MRLs that are not yet officially in force
• Active ingredients that are exempt from the requirement of a tolerance in the U.S.
• Exemptions in other countries
• MRLs for animal feed (except almond hulls and alfalfa), goat, horse, fish, shellfish, aquatic plants & algae (except seaweed)

Individuals who require more comprehensive MRL data may obtain premium subscriptions of the Global MRL Database. Access to more information and features include pending and proposed MRLs, regulation names and effective dates, the ability to save queries, and an MRL change report with email notifications.