40 CFR § 180.535 - Fluroxypyr 1-methylheptyl ester; tolerances for residues.

---
identifier: "/us/cfr/t40/s180.535"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "40 CFR § 180.535 - Fluroxypyr 1-methylheptyl ester; tolerances for residues."
title_number: 40
title_name: "Protection of Environment"
section_number: "180.535"
section_name: "Fluroxypyr 1-methylheptyl ester; tolerances for residues."
chapter_name: "ENVIRONMENTAL PROTECTION AGENCY"
subchapter_number: "E"
subchapter_name: "PESTICIDE PROGRAMS"
part_number: "180"
part_name: "TOLERANCES AND EXEMPTIONS FOR PESTICIDE CHEMICAL RESIDUES IN FOOD"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "21 U.S.C. 321(q), 346a and 371."
regulatory_source: "36 FR 22540, Nov. 25, 1971, unless otherwise noted."
cfr_part: "180"
---


# 180.535 Fluroxypyr 1-methylheptyl ester; tolerances for residues.

(a) *General.* Tolerances are established for residues of the herbicide fluroxypyr 1-methylheptyl ester, including its metabolites and degradates, in or on the commodities listed in table 1 to this paragraph (a). Compliance with the tolerance levels specified in table 1 to this paragraph (a) is to be determined by measuring only the sum of the free and conjugated forms of fluroxypyr 1-methylheptyl ester [1-methylheptyl 2-[(4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)oxy]acetate] and its metabolite fluroxypyr [2-[(4-amino-3,5-dichloro-6-fluoro-2-pyridinyl)oxy]acetic acid] calculated as the stoichiometric equivalent of fluroxypyr, in or on the commodity.

Table 1 to Paragraph (**a**)

| Commodity | Parts per million |
| --- | --- |
| Barley, forage | 12 |
| Barley, grain | 0.5 |
| Barley, hay | 20 |
| Barley, straw | 12 |
| Cattle, fat | 0.1 |
| Cattle, kidney | 1.5 |
| Cattle, meat byproducts | 0.1 |
| Corn, field, forage | 1 |
| Corn, field, grain | 0.02 |
| Corn, field, stover | 0.5 |
| Corn, sweet, forage | 1 |
| Corn, sweet, kernel plus cob with husks removed | 0.02 |
| Corn, sweet, stover | 2 |
| Fruit, pome, group 11 | 0.02 |
| Garlic, bulb | 0.03 |
| Goat, fat | 0.1 |
| Goat, kidney | 1.5 |
| Goat, meat | 0.1 |
| Goat, meat byproducts | 0.1 |
| Grain, aspirated fractions | 0.6 |
| Grass, forage, fodder and hay, group 17, forage | 120 |
| Grass, forage, fodder and hay, group 17, hay | 160 |
| Hog, fat | 0.1 |
| Hog, kidney | 1.5 |
| Hog, meat | 0.1 |
| Hog, meat byproducts | 0.1 |
| Horse, fat | 0.1 |
| Horse, kidney | 1.5 |
| Horse, meat | 0.1 |
| Horse, meat byproducts | 0.1 |
| Milk | 0.3 |
| Millet, forage | 12 |
| Millet, grain | 0.5 |
| Millet, hay | 20 |
| Millet, proso, straw | 12 |
| Oat, forage | 12 |
| Oat, grain | 0.5 |
| Oat, hay | 20 |
| Oat, straw | 12 |
| Onion, bulb | 0.03 |
| Rice, bran | 3 |
| Rice, grain | 1.5 |
| Shallot, bulb | 0.03 |
| Sheep, fat | 0.1 |
| Sheep, kidney | 1.5 |
| Sheep, meat | 0.1 |
| Sheep, meat byproducts | 0.1 |
| Sorghum, grain, forage | 2 |
| Sorghum, grain, grain | 0.02 |
| Sorghum, grain, stover | 4 |
| Teff, forage | 12 |
| Teff, grain | 0.5 |
| Teff, hay | 20 |
| Teff, straw | 12 |
| Wheat, forage | 12 |
| Wheat, grain | 0.5 |
| Wheat, hay | 20 |
| Wheat, straw | 12 |

(b) *Section 18 emergency exemptions.* [Reserved]

(c) *Tolerances with regional registrations.* [Reserved]

(d) *Indirect or inadvertent residues.* [Reserved]

[63 FR 52169, Sept. 30, 1998, as amended at 64 FR 22799, Apr. 28, 1999; 66 FR 37598, July 19, 2001; 66 FR 47971, Sept. 17, 2001; 67 FR 46884, July 17, 2002; 67 FR 60146, Sept. 25, 2002; 68 FR 75438, Dec. 31, 2003; 69 FR 2074, Jan. 14, 2004; 70 FR 3649, Jan. 26, 2005; 70 FR 7047, Feb. 10, 2005; 71 FR 76204, Dec. 20, 2006; 72 FR 73635, Dec. 28, 2007; 78 FR 3333, Jan. 16, 2013; 83 FR 29706, June 26, 2018; 91 FR 8113, Feb. 20, 2026]