In August 2021, the EPA revoked every food tolerance chlorpyrifos had. Full stop, zero residue allowed, on anything Americans eat. Two years later, a federal appeals court undid it — and as of today, the insecticide is legally back on eleven crops sold in U.S. grocery stores.
That reversal rarely makes it into the conversation about pesticide regulation, which tends to run one direction: agencies tighten, companies fight it, activists claim victory. Chlorpyrifos ran the opposite way, and the record of exactly how is public.
Start with what changed and when. In April 2021, the Ninth Circuit ordered the EPA to resolve a fifteen-year-old petition on chlorpyrifos within 60 days, either by setting safe tolerances or revoking them (League of United Latin American Citizens v. Regan, No. 19-71979). The EPA revoked them — all of them, across every food commodity — in a final rule published August 30, 2021 (86 Fed. Reg. 48315). The agency's own stated basis was that aggregate exposure, from food, water, and residential sources combined, exceeded what it could call safe under the Federal Food, Drug, and Cosmetic Act, applying a tenfold safety margin required for children. The rule also referenced research from Columbia University's Center for Children's Environmental Health, which had reported an association between prenatal chlorpyrifos exposure and neurodevelopmental outcomes in children. The EPA was explicit that it could not draw a causal line from that research to its decision, citing gaps in exposure timing and dosage data; the revocation instead rested on the aggregate-exposure math.
Then came the reversal. Sugar beet growers and other agricultural groups sued, and in November 2023 the Eighth Circuit vacated the 2021 rule (Red River Valley Sugarbeet Growers Ass'n v. Regan), finding the EPA had not followed the correct statutory procedure in revoking the tolerances outright rather than assessing them commodity by commodity. That is a procedural ruling, not a safety finding — the court did not rule that chlorpyrifos was safe, only that the EPA's process for saying it wasn't had cut a legal corner. The mandate took effect December 28, 2023, and on February 5, 2024, the EPA published a technical correction restoring the tolerances to the books (89 Fed. Reg. 7625), stating plainly that the tolerances "are legally currently in effect" because the court had vacated the rule that removed them.
What followed was a negotiated retreat rather than a full restoration. By September 30, 2024, the EPA had approved amended product labels limiting chlorpyrifos's food uses to eleven crops in specific states: alfalfa, apple, asparagus, tart cherry, citrus, cotton, peach, soybean, strawberry, sugar beet, and spring and winter wheat. Then, on December 10, 2024, the EPA proposed a new rule to formally revoke tolerances on every use outside those eleven crops (89 Fed. Reg. 99184, Docket EPA-HQ-OPP-2024-0431) — a roughly 70 percent cut in average annual chlorpyrifos use compared with historical levels. That comment period closed in March 2025. As of August 17, 2026, no final rule has been issued. The current version of 40 CFR 180.342, in effect this month, still lists specific residue limits for exactly the commodities the reduced-use plan covers, including apple at 0.01 ppm and alfalfa hay at 13 ppm — meaning the interim, narrower legal status is the one actually in force on shelves right now, not the full ban and not the full reinstatement.
Where does the rest of the world land on this? The European Union did not revoke chlorpyrifos's approval in response to litigation — it declined to renew the approval in the first place, effective January 2020, with member states required to pull existing authorizations within a month. The EU's implementing regulation is specific about why: the European Food Safety Authority concluded it could not rule out genotoxic potential based on positive results in laboratory studies, reported developmental neurotoxicity effects in animal testing, and cited epidemiological evidence of an association between chlorpyrifos exposure during development and adverse neurodevelopmental outcomes in children. That's a broader, more precautionary standard than the aggregate-exposure math the EPA used in 2021 — the EU's own scientific authority treated the mechanistic and developmental signals as sufficient on their own, without needing to complete the kind of exposure-reconstruction analysis the EPA said it lacked. One classification that does not enter this divergence: the International Agency for Research on Cancer has not evaluated chlorpyrifos at all. Its 2017 review of organophosphate insecticides covered malathion, parathion, diazinon, and tetrachlorvinphos, but chlorpyrifos wasn't included. There is no IARC group to cite here, in either direction.
None of this shows up on a package. Chlorpyrifos is a pesticide applied during growing, not a labeled ingredient, so there's no wording on a bag of apples or a box of strawberries to flag it the way an additive's name would appear on an ingredient panel. The only way to know whether a specific conventionally grown crop was legally allowed to carry chlorpyrifos residue is to know which of the eleven approved crops it falls under, and in which states — information that lives in EPA dockets, not on shelf labels. Products certified USDA Organic are a separate case: synthetic pesticides including chlorpyrifos are prohibited under organic certification regardless of what EPA tolerances currently allow for conventional versions of the same crop.
This is exactly the kind of gap PurityIQ exists to close. The app doesn't render a verdict on chlorpyrifos, and it isn't trying to settle the disagreement between the EPA's exposure math and the EU's precautionary standard — that's a live, unresolved regulatory question, and pretending otherwise would be dishonest. What it does is put the actual record in front of you when you're standing at the shelf: which government body said what, when, under what legal standard, cited back to the primary document, so you're making the call with the same facts the regulators are working from.
Sources:
Federal Register: Chlorpyrifos; Tolerance Revocations, 86 Fed. Reg. 48315 (Aug. 30, 2021) | https://www.federalregister.gov/documents/2021/08/30/2021-18091/chlorpyrifos-tolerance-revocations
League of United Latin American Citizens v. Regan, No. 19-71979 (9th Cir. Apr. 29, 2021) | https://law.justia.com/cases/federal/appellate-courts/ca9/19-71979/19-71979-2021-04-29.html
Federal Register: Chlorpyrifos; Reinstatement of Tolerances, 89 Fed. Reg. 7625 (Feb. 5, 2024) | https://www.federalregister.gov/documents/2024/02/05/2024-02153/chlorpyrifos-reinstatement-of-tolerances
EPA, Frequently Asked Questions about the Current Status of Chlorpyrifos and Anticipated Path Forward (last updated Sept. 8, 2025) | https://www.epa.gov/ingredients-used-pesticide-products/frequently-asked-questions-about-current-status-chlorpyrifos
Federal Register: Chlorpyrifos; Tolerance Revocation (proposed rule), 89 Fed. Reg. 99184 (Dec. 10, 2024), Docket EPA-HQ-OPP-2024-0431 | https://www.federalregister.gov/documents/2024/12/10/2024-28332/chlorpyrifos-tolerance-revocation
EPA, EPA Proposes Rule to Revoke Most Food Uses of the Insecticide Chlorpyrifos | https://www.epa.gov/pesticides/epa-proposes-rule-revoke-most-food-uses-insecticide-chlorpyrifos
eCFR, 40 CFR 180.342 — Chlorpyrifos; tolerances for residues (current version) | https://www.ecfr.gov/current/title-40/chapter-I/subchapter-E/part-180/subpart-C/section-180.342
Commission Implementing Regulation (EU) 2020/18 of 10 January 2020 concerning the non-renewal of the approval of chlorpyrifos | https://eur-lex.europa.eu/eli/reg_impl/2020/18/oj
IARC Monographs Volume 112: Some Organophosphate Insecticides and Herbicides (2017) | https://www.iarc.who.int/news-events/iarc-monographs-volume-112-evaluation-of-five-organophosphate-insecticides-and-herbicides