Three federal agencies share responsibility for regulating pesticides in the United States: the Environmental Protection Agency (EPA), the Food and Drug Administration (FDA), and the U.S. Department of Agriculture (USDA). The EPA is the central authority, deciding which pesticides can be sold and how they can be used. The FDA and USDA handle food safety monitoring, and state governments carry out most day-to-day enforcement.
The EPA: Registration and Risk Assessment
No pesticide can be legally sold or distributed in the United States until the EPA registers it. The agency operates under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), which requires manufacturers to submit extensive data proving that a product will work as intended “without unreasonable adverse effects on the environment.” That phrase is the legal standard the EPA applies to every registration decision, and it covers risks to human health, wildlife, water sources, and soil.
To get a pesticide registered, a company must provide data on toxicity, environmental fate, residue chemistry, and effects on non-target species like birds, fish, and mammals. The EPA uses specific thresholds to decide whether a pesticide poses too great a risk to wildlife. If residues in the diet of exposed birds or mammals reach even one-fifth of the lethal dose, or if waterborne residues hit one-tenth of the lethal concentration for aquatic life, the product may be classified as restricted use, meaning only certified applicators can buy and apply it.
Once registered, every pesticide goes through a review cycle at least every 15 years. During this re-evaluation, the EPA reassesses whether the product still meets safety standards given updated science. Dozens of pesticides are in various stages of review at any given time, from preliminary risk assessments to final decisions on whether to keep, restrict, or cancel a registration.
The FDA: Checking What Ends Up in Food
While the EPA decides how much pesticide residue is allowed on food (called a “tolerance”), the FDA is the agency that actually checks whether those limits are being followed. The FDA monitors roughly 780 different pesticides and industrial compounds across domestic and imported foods, including fruits, vegetables, grains, dairy, fish, and shellfish.
When residues exceed the EPA’s tolerance for a given pesticide-and-food combination, or when a pesticide shows up on a food it was never approved for, the FDA can act. For domestic products, that means warning letters to growers or seizing contaminated food. For imports, the consequences are often swifter: a single violative shipment can trigger “detention without physical examination,” essentially a standing order to block future shipments from that firm without even testing them first. In fiscal year 2023, the FDA flagged 28 domestic samples and 348 import samples as violative.
One important gap: the FDA does not monitor meat, poultry, catfish, or certain egg products. That responsibility falls to the USDA’s Food Safety and Inspection Service.
The USDA: Testing and Data Collection
The USDA plays a complementary role through its Pesticide Data Program (PDP), which samples and tests agricultural commodities in the U.S. food supply. The program places special emphasis on foods highly consumed by infants and children, reflecting a broader federal priority on protecting younger populations from pesticide exposure. PDP data feeds into the EPA’s risk assessments and helps the FDA target its own monitoring efforts.
How States Fit Into the System
States hold primary enforcement responsibility for pesticide use violations under FIFRA. In practice, this means state agencies, not the EPA, investigate most complaints about pesticide misuse, such as a farmer spraying a product in a way the label prohibits or a pest control company applying chemicals without proper certification. States can also impose their own regulations that go beyond federal requirements. California, for example, requires its own state-level registration for pesticides and maintains stricter rules for certain chemicals.
If a state fails to enforce federal standards adequately, the EPA has the authority to rescind that state’s primary enforcement role, though this is rare. States can also refer difficult cases to the EPA for federal enforcement action.
Special Protections for Children
The Food Quality Protection Act of 1996 changed how the EPA sets safety limits for pesticides in food by adding a mandatory tenfold safety factor for infants and children. This means that when the EPA calculates the safe exposure level for a pesticide, it divides that level by an additional factor of ten to account for the fact that children’s developing bodies may be more vulnerable. The EPA can use a smaller safety factor only if it has reliable data showing that a different margin would still protect children. This law also required the EPA to consider “aggregate exposure,” meaning all the ways a child might encounter a pesticide: through food, drinking water, and residential use combined.
Protecting Farmworkers
The EPA’s Worker Protection Standard (WPS) sets safety rules for the roughly two million agricultural workers and pesticide handlers in the country. Employers must provide annual pesticide safety training, supply and maintain personal protective equipment, and post warning signs or give oral notification about treated areas. Workers cannot enter a treated field until a restricted-entry interval has passed. Handlers who are required to wear respirators must receive a medical evaluation, a fit test, and specific training before using one.
Who Can Apply Restricted Pesticides
Federal law requires anyone who applies or supervises the use of restricted-use pesticides to be certified. There are two categories. Private applicators, typically farmers treating their own land, must demonstrate knowledge of pest problems, proper pesticide handling, and the ability to read and follow label instructions. They can be certified by passing a test or completing a training course. Commercial applicators face a higher bar: they must pass written exams covering core pesticide safety and at least one specific application category, such as forestry or structural pest control. Both types of applicators must recertify periodically, generally every three to five years through continuing education.
Endangered Species and Pesticides
The EPA is also required to ensure that pesticide use does not jeopardize threatened or endangered species, a responsibility that has historically lagged behind the agency’s other obligations. In 2022, the EPA released a formal workplan to address this gap, outlining strategies for protecting vulnerable species from herbicides, insecticides, and rodenticides. The plan includes targeted efforts for regions with high concentrations of listed species, such as Hawaii, and commits the agency to building species protections into the registration review process earlier rather than treating them as an afterthought.