CFR - Code of Federal Regulations Title 21

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[Code of Federal Regulations]

[Title 21, Volume 6]

[CITE: 21CFR556]

TITLE 21--FOOD AND DRUGS
CHAPTER I--FOOD AND DRUG ADMINISTRATION
DEPARTMENT OF HEALTH AND HUMAN SERVICES
					
SUBCHAPTER E - ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS
					
							PART 556TOLERANCES FOR RESIDUES OF NEW ANIMAL DRUGS IN FOOD

Subpart A - General Provisions

Sec. 556.1 Scope.

(a) The Federal Food, Drug, and Cosmetic Act requires an applicant seeking approval or conditional approval of a new animal drug to submit a proposed tolerance as part of its new animal drug application when such a tolerance is needed to assure that the proposed use of the new animal drug will be safe (see sections 512(b)(1)(H) and 571(a)(2)(A) of the Federal Food, Drug, and Cosmetic Act). FDA assigns tolerances for animal drugs used in food-producing animals as part of the application approval process. Tolerances for approved and conditionally approved new animal drugs are codified in subpart B of this part.

(b) Compounds that have been found to be carcinogenic are regulated under subpart E of part 500 of this chapter.

Sec. 556.3 Definitions.

As used in this part:

Acceptable daily intake (ADI) means the daily intake which, during up to an entire life of a human, appears to be without adverse effects or harm to the health of the consumer. The ADI most often will be set on the basis of the drug's toxicological, microbiological, or pharmacological properties. It is usually expressed in micrograms or milligrams of the chemical per kilogram of body weight per day.

Acute reference dose (ARfD) means an estimate of the amount of residues expressed on a body weight basis that can be ingested in a period of 24 hours or less without adverse effects or harm to the health of the human consumer.

Edible tissues means muscle, liver, kidney, fat, skin with fat in natural proportions, whole eggs, whole milk, and honey.

Marker residue means the residue whose concentration is in a known relationship to the concentration of total residue in an edible tissue.

mg/kg means milligrams per kilogram.

Not required, in reference to tolerances in this part, means that at the time of approval:

(1) No withdrawal period was necessary for residues of the drug to deplete to or below the concentrations considered to be safe, or an adequate withdrawal period was inherent in the proposed drug use, and there was a rapid depletion of residues, so there was no concern about residues resulting from misuse or overdosing; or

(2) No withdrawal period was necessary because the drug was poorly absorbed or metabolized rapidly so as to make selection of an analyte impractical or impossible.

ppb means parts per billion (equivalent to nanograms per gram (ng/g) or [micro]g/kg).

ppm means parts per million (equivalent to micrograms per gram ([micro]g/g) or mg/kg).

ppt means parts per trillion (equivalent to picograms per gram (pg/g) or nanograms per kilogram (ng/kg)).

Residue means any compound present in edible tissues that results from the use of a drug, and includes the drug, its metabolites, and any other substance formed in or on food because of the drug's use.

Target tissue means the edible tissue selected to monitor for residues in the target animals.

Tolerance means the maximum concentration of a marker residue, or other residue indicated for monitoring, that can legally remain in a specific edible tissue of a treated animal.

Total residue means the aggregate of all compounds that results from the use of an animal drug, including the drug, its metabolites, and any other substances formed in or on food because of such drug use.

[micro]g/kg means microgram per kilogram.

Zero, in reference to tolerances in this part, means any residues detected in the edible tissue renders it unsafe.

Sec. 556.5 General considerations.

(a) The tolerances listed in subpart B of this part pertain only to the species and production classes of the animal for which the drug use has been approved or conditionally approved. Approved and conditionally approved conditions of use in parts 516, 520, 522, 524, 526, 529, and 558 of this chapter, including the species and production classes of animals, are referenced in each tolerance section in subpart B of this part.

(b) All tolerances refer to the concentrations of a marker residue, or other residue indicated for monitoring, permitted in uncooked tissues.

(c) After a tolerance is listed, the finding that the concentration of the marker residue in the target tissue from a tested animal is at or below the tolerance indicates that all edible tissues (excluding milk and eggs unless otherwise indicated) from that tested animal are safe for human consumption. If a listed tolerance is not expressly linked to a target tissue, then the tolerance is specific only for the named edible tissue and inferences cannot be made about the safety of the other edible tissues from the tested animal.

(d) FDA requires that a drug sponsor submit a practicable method as part of their new animal drug application. FDA uses the practicable method to determine the quantity of the drug residues that can safely remain in edible tissues (i.e., the tolerance), the withdrawal period, and any other use restrictions necessary to ensure that the proposed use of the drug will be safe.

Subpart B - Specific Tolerances for Residues of Approved and Conditionally Approved New Animal Drugs

Sec. 556.34 Albendazole.

(a) Acceptable daily intake (ADI). The ADI for total residue of albendazole is 5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for albendazole 2-aminosulfone (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 0.2 ppm.

(ii) Muscle: 0.05 ppm.

(2) Sheep. (i) Liver (target tissue): 0.25 ppm.

(ii) Muscle: 0.05 ppm.

(3) Goat. (i) Liver (target tissue): 0.25 ppm.

(ii) [Reserved]

Sec. 556.36 Altrenogest.

(a) Acceptable daily intake (ADI). The ADI for total residue of altrenogest is 0.04 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for altrenogest (marker residue) are:

(1) Swine. (i) Liver (target tissue): 4 ppb.

(ii) Muscle: 1 ppb.

(2) [Reserved]

Sec. 556.38 Amoxicillin.

(a) [Reserved]

(b) Tolerances. The tolerance for amoxicillin is:

(1) Cattle. Edible tissues: 0.01 ppm.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 86 FR 13188, Mar. 8, 2021]

Sec. 556.40 Ampicillin.

(a) [Reserved]

(b) Tolerances. The tolerances for ampicillin are:

(1) Cattle. Edible tissues: 0.01 ppm.

(2) Swine. Edible tissues: 0.01 ppm.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18120, Apr. 1, 2020]

Sec. 556.50 Amprolium.

(a) [Reserved]

(b) Tolerances. The tolerances for amprolium are:

(1) Cattle. (i) Liver, kidney, and muscle: 0.5 ppm.

(ii) Fat: 2.0 ppm.

(2) Chickens and turkeys. (i) Liver and kidney: 1 ppm.

(ii) Muscle: 0.5 ppm.

(iii) Eggs:

(A) Egg yolks: 8 ppm.

(B) Whole eggs: 4 ppm.

(3) Pheasants. (i) Liver: 1 ppm.

(ii) Muscle: 0.5 ppm.

Sec. 556.52 Apramycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of apramycin is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for apramycin (marker residue) is:

(1) Swine. Kidney (target tissue): 0.1 ppm.

(2) [Reserved]

Sec. 556.60 Avilamycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of avilamycin is 1.1 mg/kg of body weight per day.

(b) Tolerances. The tolerances for avilamycin are:

(1) Chickens. Edible tissues (excluding eggs): Not required.

(2) Swine. Edible tissues: Not required.

Sec. 556.68 Azaperone.

(a) Acceptable daily intake (ADI). The ADI for total residue of azaperone is 0.63 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for azaperone is:

(1) Swine. Edible tissues: Not required.

(2) [Reserved]

Sec. 556.70 Bacitracin.

(a) Acceptable daily intake (ADI). The ADI for total residue of bacitracin is 0.05 mg/kg of body weight per day.

(b) Tolerances. The tolerances for bacitracin are:

(1) Cattle. Edible tissues: 0.5 ppm.

(2) Chickens, turkeys, pheasants, quail. Edible tissues: 0.5 ppm.

(3) Swine. Edible tissues: 0.5 ppm.

Sec. 556.75 Bambermycins.

(a) [Reserved]

(b) Tolerances. The tolerances for bambermycins are:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) Chickens and turkeys. Edible tissues (excluding eggs): Not required.

(3) Swine. Edible tissues: Not required.

Sec. 556.100 Carbadox.

(a) [Reserved]

(b) Tolerances. The tolerance for quinoxaline-2-carboxylic acid (marker residue) is:

(1) Swine. Liver (target tissue): 30 ppb.

(2) [Reserved]

Sec. 556.110 Carbomycin.

(a) [Reserved]

(b) Tolerances. The tolerance for carbomycin is:

(1) Chickens. Edible tissues (excluding eggs): Zero.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 88 FR 55567, Aug. 16, 2023]

Sec. 556.113 Ceftiofur.

(a) Acceptable daily intake and acute reference dose - (1) Acceptable daily intake (ADI). The ADI for total residue of ceftiofur is 30 [micro]g/kg of body weight per day.

(2) Acute reference dose (ARfD). The ARfD for total residue of ceftiofur is 0.830 mg/kg of body weight.

(b) Tolerances. The tolerances for desfuroylceftiofur (marker residue) are:

(1) Cattle. (i) Kidney (target tissue): 0.4 ppm.

(ii) Liver: 2 ppm.

(iii) Muscle: 1 ppm.

(iv) Milk: 0.1 ppm.

(2) Chickens and turkeys. Edible tissues (excluding eggs): Not required.

(3) Goats. (i) Kidney (target tissue): 8 ppm.

(ii) Liver: 2 ppm.

(iii) Muscle: 1 ppm.

(iv) Milk: 0.1 ppm.

(4) Sheep. Edible tissues (excluding milk): Not required.

(5) Swine. (i) Kidney (target tissue): 0.25 ppm.

(ii) Liver: 3 ppm.

(iii) Muscle: 2 ppm.

Sec. 556.115 Cephapirin.

(a) [Reserved]

(b) Tolerances. The tolerances for cephapirin are:

(1) Cattle. (i) Edible tissues (excluding milk): 0.1 ppm.

(ii) Milk: 0.02 ppm.

(2) [Reserved]

Sec. 556.118 Chloramine-T.

(a) Acceptable daily intake (ADI). The ADI for total residue of chloramine-T is 5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for para -toluenesulfonamide (marker residue) is:

(1) Fish. Muscle/skin (target tissue): 0.9 ppm.

(2) [Reserved]

Sec. 556.120 Chlorhexidine.

(a) [Reserved]

(b) Tolerances. The tolerance for chlorhexidine is:

(1) Cattle. Edible tissues (excluding milk): Zero.

(2) [Reserved]

Sec. 556.150 Chlortetracycline.

(a) Acceptable daily intake (ADI). The ADI for total residue of tetracyclines including chlortetracycline, oxytetracycline, and tetracycline is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for the sum of tetracycline residues are:

(1) Cattle. (i) Liver: 6 ppm.

(ii) Kidney and fat: 12 ppm.

(iii) Muscle: 2 ppm.

(2) Chickens, turkeys, and ducks. (i) Liver: 6 ppm.

(ii) Kidney and fat: 12 ppm.

(iii) Muscle: 2 ppm.

(iv) Eggs: 0.4 ppm for chlortetracycline only.

(3) Sheep. (i) Liver: 6 ppm.

(ii) Kidney and fat: 12 ppm.

(iii) Muscle: 2 ppm.

(4) Swine. (i) Liver: 6 ppm.

(ii) Kidney and fat: 12 ppm.

(iii) Muscle: 2 ppm.

Sec. 556.160 Clopidol.

(a) [Reserved]

(b) Tolerances. The tolerances for clopidol are:

(1) Chickens and turkeys. (i) Liver and kidney: 15 ppm.

(ii) Muscle: 5 ppm.

(2) [Reserved]

Sec. 556.163 Clorsulon.

(a) Acceptable daily intake (ADI). The ADI for total residue of clorsulon is 8 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for clorsulon (marker residue) are:

(1) Cattle. (i) Kidney (target tissue): 1.0 ppm.

(ii) Muscle: 0.1 ppm.

(2) [Reserved]

Sec. 556.165 Cloxacillin.

(a) [Reserved]

(b) Tolerances. The tolerance for cloxacillin is:

(1) Cattle. Edible tissues: 0.01 ppm.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020; 86 FR 13188, Mar. 8, 2021]

Sec. 556.167 Colistimethate.

(a) [Reserved]

(b) Tolerances. The tolerance for colistimethate is:

(1) Chickens. Edible tissues (excluding eggs): Not required.

(2) [Reserved]

Sec. 556.168 Coumaphos.

(a) [Reserved]

(b) Tolerances. The tolerances for coumaphos (measured as coumaphos and its oxygen analog, O,O-diethyl O-3- chloro-4-methyl-2-oxo-2 H-1- benzopyran-7-yl phosphate) are:

(1) Chickens. (i) Edible tissues (excluding eggs): 1 ppm.

(ii) Eggs: 0.1 ppm.

(2) [Reserved]

[86 FR 14821, Mar. 19, 2021]

Sec. 556.169 Danofloxacin.

(a) Acceptable daily intake (ADI). The ADI for total residue of danofloxacin is 2.4 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for danofloxacin (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 0.2 ppm.

(ii) Muscle: 0.2 ppm.

(2) [Reserved]

Sec. 556.170 Decoquinate.

(a) Acceptable daily intake (ADI). The ADI for total residue of decoquinate is 75 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for decoquinate are:

(1) Cattle. (i) Muscle: 1 ppm.

(ii) Other edible tissues (excluding milk): 2 ppm.

(2) Chickens. (i) Muscle: 1 ppm.

(ii) Other edible tissues (excluding eggs): 2 ppm.

(3) Goats. (i) Muscle: 1 ppm.

(ii) Other edible tissues (excluding milk): 2 ppm.

[84 FR 32993, July 11, 2019, as amended at 86 FR 13188, Mar. 8, 2021]

Sec. 556.180 Dichlorvos.

(a) [Reserved]

(b) Tolerances. The tolerance for dichlorvos is:

(1) Swine. Edible tissues: 0.1 ppm.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 86 FR 13188, Mar. 8, 2021]

Sec. 556.185 Diclazuril.

(a) Acceptable daily intake (ADI). The ADI for total residue of diclazuril is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for diclazuril are:

(1) Chickens and turkeys. (i) Liver: 3 ppm.

(ii) Muscle: 0.5 ppm.

(iii) Skin/fat: 1 ppm.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 86 FR 13188, Mar. 8, 2021]

Sec. 556.200 Dihydrostreptomycin.

(a) [Reserved]

(b) Tolerances. The tolerances for dihydrostreptomycin are:

(1) Cattle. (i) Kidney: 2.0 ppm.

(ii) Other edible tissues (excluding milk): 0.5 ppm.

(iii) Milk: 0.125 ppm.

(2) Swine. (i) Kidney: 2.0 ppm.

(ii) Other edible tissues: 0.5 ppm.

Sec. 556.222 Doramectin.

(a) Acceptable daily intake (ADI). The ADI for total residue of doramectin is 0.75 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for doramectin (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 300 ppb.

(ii) Muscle: 30 ppb.

(2) Swine. Liver (target tissue): 160 ppb.

[84 FR 32993, July 11, 2019, as amended at 88 FR 16549, Mar. 20, 2023]

Sec. 556.224 Efrotomycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of efrotomycin is 10 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for efrotomycin is:

(1) Swine. Edible tissues: Not required.

(2) [Reserved]

Sec. 556.226 Enrofloxacin.

(a) Acceptable daily intake (ADI). The ADI for total residue of enrofloxacin is 3 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for enrofloxacin are:

(1) Cattle. Liver (target tissue): 0.1 ppm desethylene ciprofloxacin (marker residue).

(2) Swine. Liver (target tissue): 0.5 ppm enrofloxacin (marker residue).

[84 FR 32993, July 11, 2019, as amended at 86 FR 13188, Mar. 8, 2021]

Sec. 556.227 Eprinomectin.

(a) Acceptable daily intake (ADI). The ADI for total residue of eprinomectin is 10 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for eprinomectin B1a (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 1.5 ppm.

(ii) Muscle: 100 ppb.

(iii) Milk: 12 ppb.

(2) [Reserved]

Sec. 556.230 Erythromycin.

(a) [Reserved]

(b) Tolerances. The tolerances for erythromycin are:

(1) Cattle. (i) Edible tissues (excluding milk): 0.1 ppm.

(ii) Milk: Zero.

(2) Chickens and turkeys. (i) Edible tissues (excluding eggs): 0.125 ppm.

(ii) Eggs: 0.025 ppm.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.240 Estradiol and related esters.

(a) [Reserved]

(b) Residues. Residues of estradiol are not permitted in excess of the following increments above the concentrations of estradiol naturally present in untreated animals:

(1) Cattle. (i) Muscle: 0.2 ppb.

(ii) Liver: 0.6 ppb.

(iii) Kidney: 1.2 ppb.

(iv) Fat: 1.2 ppb.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 87 FR 17947, Mar. 29, 2022]

Sec. 556.260 Ethopabate.

(a) [Reserved]

(b) Tolerances. The tolerances for ethopabate, measured as metaphenetidine, are:

(1) Chickens. (i) Liver: 1.5 ppm.

(ii) Kidney: 1.5 ppm.

(iii) Muscle: 0.5 ppm.

(2) [Reserved]

Sec. 556.273 Famphur.

(a) [Reserved]

(b) Tolerances. The tolerance for famphur including its oxygen analog is:

(1) Cattle. Edible tissues (excluding milk): 0.1 ppm.

(2) [Reserved]

Sec. 556.275 Fenbendazole.

(a) Acceptable daily intake (ADI). The ADI for total residue of fenbendazole is 40 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for fenbendazole are:

(1) Cattle. (i) Liver (target tissue): 0.8 ppm fenbendazole (marker residue).

(ii) Milk: 0.22 ppm fenbendazole sulfoxide (marker residue).

(2) Chickens. (i) Liver (target tissue): 5.2 ppm fenbendazole sulfone (marker residue).

(ii) Eggs: 1.8 ppm fenbendazole sulfone (marker residue).

(3) Goats. (i) Liver (target tissue): 0.8 ppm fenbendazole (marker residue).

(ii) [Reserved]

(4) Swine. (i) Liver (target tissue): 3.2 ppm fenbendazole (marker residue).

(ii) [Reserved]

(5) Turkeys. (i) Liver (target tissue): 6 ppm fenbendazole sulfone (marker residue).

(ii) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 86 FR 57998, Oct. 20, 2021; 86 FR 61686, Nov. 8, 2021]

Sec. 556.277 Fenprostalene.

(a) Acceptable daily intake (ADI). The ADI for total residue of fenprostalene is 0.08 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for fenprostalene are:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) Swine. Edible tissues: Not required.

Sec. 556.280 Fenthion.

(a) [Reserved]

(b) Tolerances. The tolerance for fenthion is:

(1) Cattle. Edible tissues (excluding milk): 0.1 ppm.

(2) [Reserved]

Sec. 556.283 Florfenicol.

(a) Acceptable daily intake (ADI). The ADI for total residue of florfenicol is 10 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for florfenicol amine (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 3.7 ppm.

(ii) Muscle: 0.3 ppm.

(2) Swine. (i) Liver (target tissue): 2.5 ppm.

(ii) Muscle: 0.2 ppm.

(3) Catfish. Muscle (target tissue): 1 ppm.

(4) Freshwater-reared warmwater finfish (other than catfish) and salmonids. Muscle/skin (target tissue): 1 ppm.

Sec. 556.286 Flunixin.

(a) Acceptable daily intake (ADI). The ADI for total residue of flunixin is 0.72 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for flunixin are:

(1) Cattle. (i) Liver (target tissue): 125 ppb flunixin free acid (marker residue).

(ii) Muscle: 25 ppb flunixin free acid.

(iii) Milk: 2 ppb 5-hydroxy flunixin (marker residue).

(2) Swine. (i) Liver (target tissue): 30 ppb flunixin free acid (marker residue).

(ii) Muscle: 25 ppb flunixin free acid.

Sec. 556.292 Gamithromycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of gamithromycin is 10 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for gamithromycin (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 500 ppb.

(ii) Muscle: 150 ppb.

(2) [Reserved]

Sec. 556.300 Gentamicin.

(a) Acceptable daily intake (ADI). The ADI for total residue of gentamicin is 60 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for gentamicin are:

(1) Chickens and turkeys. Edible tissues (excluding eggs): 0.1 ppm.

(2) Swine. (i) Liver: 0.3 ppm.

(ii) Kidney (target tissue): 0.4 ppm gentamicin (marker residue).

(iii) Fat: 0.4 ppm.

(iv) Muscle: 0.1 ppm.

(c) Related conditions of use. See §§ 520.1044a, 520.1044b, 520.1044c, 522.1044, 524.1044e, and 529.1044b of this chapter.

[84 FR 32993, July 11, 2019, as amended at 86 FR 13188, Mar. 8, 2021]

Sec. 556.304 Gonadotropin.

(a) Acceptable daily intake (ADI). The ADI for residues of total gonadotropins (human chorionic gonadotropin and pregnant mare serum gonadotropin) is 42.25 International Units per kilogram of body weight per day.

(b) Tolerances. The tolerances for gonadotropin are:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) Fish. Edible tissues: Not required.

(3) Swine. Edible tissues: Not required.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.308 Halofuginone.

(a) Acceptable daily intake (ADI). The ADI for total residue of halofuginone hydrobromide is 0.7 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for halofuginone (marker residue) are:

(1) Chickens. Liver (target tissue): 0.16 ppm.

(2) Turkeys. Liver (target tissue): 0.13 ppm.

Sec. 556.310 Haloxon.

(a) [Reserved]

(b) Tolerances. The tolerance for haloxon is:

(1) Cattle. Edible tissues (excluding milk): 0.1 ppm.

(2) [Reserved]

Sec. 556.316 Hetacillin.

(a) [Reserved]

(b) Tolerances. The tolerances for ampicillin (marker residue for hetacillin) are:

(1) Cattle. Edible tissues: 0.01 ppm.

(2) [Reserved]

[84 FR 53311, Oct. 7, 2019]

Sec. 556.330 Hygromycin B.

(a) [Reserved]

(b) Tolerances. The tolerances for hygromycin B are:

(1) Chickens. Edible tissues: Zero.

(2) Swine. Edible tissues: Zero.

Sec. 556.344 Ivermectin.

(a) Acceptable daily intake (ADI). The ADI for total residue of ivermectin is 5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for 22,23-dihydroavermectin B1a (marker residue) are:

(1) American bison. Liver (target tissue): 15 ppb.

(2) Cattle. (i) Liver (target tissue): 1.6 ppm.

(ii) Muscle: 650 ppb.

(3) Reindeer. Liver (target tissue): 15 ppb.

(4) Sheep. Liver (target tissue): 30 ppb.

(5) Swine. (i) Liver (target tissue): 20 ppb.

(ii) Muscle: 20 ppb.

(c) Related conditions of use. See §§ 520.1192, 520.1195, 520.1197, 522.1192, 522.1193, 524.1193, and 558.300 of this chapter.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.345 Ketoprofen.

(a) Acceptable daily intake (ADI). The ADI for total residue of ketoprofen is 5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for ketoprofen (marker residue) are:

(1) Cattle. (i) Kidney (target tissue): 0.36 ppm.

(ii) [Reserved]

[86 FR 61686, Nov. 8, 2021]

Sec. 556.346 Laidlomycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of laidlomycin is 7.5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for laidlomycin (marker residue) is:

(1) Cattle. Liver (target tissue): 0.2 ppm.

(2) [Reserved]

Sec. 556.347 Lasalocid.

(a) Acceptable daily intake (ADI). The ADI for total residue of lasalocid is 10 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for lasalocid (marker residue) are:

(1) Cattle. Liver (target tissue): 0.7 ppm.

(2) Chickens. (i) Skin with adhering fat (target tissue): 1.2 ppm.

(ii) Liver: 0.4 ppm.

(3) Rabbits. Liver (target tissue): 0.7 ppm.

(4) Sheep. Liver (target tissue): 1.0 ppm.

(5) Turkeys. (i) Liver (target tissue): 0.4 ppm.

(ii) Skin with adhering fat: 0.4 ppm.

Sec. 556.350 Levamisole.

(a) [Reserved]

(b) Tolerances. The tolerances for levamisole are:

(1) Cattle. Edible tissues (excluding milk): 0.1 ppm.

(2) Sheep. Edible tissues (excluding milk): 0.1 ppm.

(3) Swine. Edible tissues: 0.1 ppm.

(c) Related conditions of use. See §§ 520.1242a, 520.1242b, 520.1242d, 520.1242e, 520.1242f, 520.1242g, 522.1242, and 524.1240 of this chapter.

Sec. 556.360 Lincomycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of lincomycin is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for lincomycin are:

(1) Chickens. Edible tissues (excluding eggs): Not required.

(2) Swine. (i) Liver: 0.6 ppm.

(ii) Muscle: 0.1 ppm.

(3) Honey. 750 ppb.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Editorial Note:

At 86 FR 13188, Mar. 8, 2021, in § 556.360, paragraph (c) was amended; however, the amendment could not be incorporated due to inaccurate amendatory instruction.

Sec. 556.370 Lubabegron.

(a) Acceptable daily intake (ADI). The ADI for total residues of lubabegron is 3 micrograms per kilogram of body weight per day.

(b) Tolerances. The tolerances for lubabegron (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 10 ppb.

(ii) Muscle: 3 ppb.

(iii) Kidney: 20 ppb.

(2) [Reserved]

[84 FR 12494, Apr. 2, 2019, as amended at 87 FR 17947, Mar. 29, 2022]

Sec. 556.375 Maduramicin.

(a) [Reserved]

(b) Tolerances. The tolerance for maduramicin (marker residue) is:

(1) Chickens. Fat (target tissue): 0.38 ppm.

(2) [Reserved]

Sec. 556.380 Melengestrol.

(a) [Reserved]

(b) Tolerances. The tolerance for melengestrol is:

(1) Cattle. Fat: 25 ppb.

(2) [Reserved]

Sec. 556.410 Metoserpate.

(a) [Reserved]

(b) Tolerances. The tolerance for metoserpate is:

(1) Chickens. Edible tissues (excluding eggs): 0.02 ppm.

(2) [Reserved]

Sec. 556.420 Monensin.

(a) Acceptable daily intake (ADI). The ADI for total residue of monensin is 12.5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for monensin are:

(1) Cattle. (i) Liver: 0.10 ppm.

(ii) Muscle, kidney, and fat: 0.05 ppm.

(iii) Milk: Not required.

(2) Chickens and turkeys. Edible tissues (excluding eggs): Not required.

(3) Goats. Edible tissues (excluding milk): 0.05 ppm.

(4) Quail. Edible tissues (excluding eggs): Not required.

Sec. 556.425 Morantel.

(a) Acceptable daily intake (ADI). The ADI for total residue of morantel tartrate is 10 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for N-methyl-1,3-propanediamine (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 0.7 ppm.

(ii) Milk: Not required.

(2) Goats. (i) Liver (target tissue): 0.7 ppm.

(ii) Milk: Not required.

Sec. 556.426 Moxidectin.

(a) Acceptable daily intake (ADI). The ADI for total residue of moxidectin is 4 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for moxidectin (marker residue) are:

(1) Cattle. (i) Fat (target tissue): 900 ppb.

(ii) Liver: 200 ppb.

(iii) Muscle: 50 ppb.

(iv) Milk: 40 ppb.

(2) Sheep. (i) Fat (target tissue): 900 ppb.

(ii) Liver: 200 ppb.

(iii) Muscle: 50 ppb.

Sec. 556.428 Narasin.

(a) Acceptable daily intake (ADI). The ADI for total residue of narasin is 5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for narasin (marker residue) is:

(1) Chickens. Abdominal fat (target tissue): 480 ppb.

(2) [Reserved]

Sec. 556.430 Neomycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of neomycin is 6 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for neomycin are:

(1) Cattle. (i) Kidney (target tissue): 7.2 ppm.

(ii) Liver: 3.6 ppm.

(iii) Muscle: 1.2 ppm.

(iv) Fat: 7.2 ppm.

(v) Milk: 0.15 ppm.

(2) Sheep and goats. (i) Kidney (target tissue): 7.2 ppm.

(ii) Liver: 3.6 ppm.

(iii) Muscle: 1.2 ppm.

(iv) Fat: 7.2 ppm.

(v) Milk: 0.15 ppm.

(3) Swine. (i) Kidney (target tissue): 7.2 ppm.

(ii) Liver: 3.6 ppm.

(iii) Muscle: 1.2 ppm.

(iv) Fat: 7.2 ppm.

(4) Turkeys. (i) Skin with adhering fat: 7.2 ppm.

(ii) Liver: 3.6 ppm.

(iii) Muscle: 1.2 ppm.

Sec. 556.445 Nicarbazin.

(a) Acceptable daily intake (ADI). The ADI for total residues of nicarbazin (4,4'-dinitrocarbanilide and 2-hydroxy-4,6-dimethylpyrimidine) is 200 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for 4,4'-dinitrocarbanilide (marker residue) is:

(1) Chickens. Liver (target tissue): 52 ppm.

(2) [Reserved]

Sec. 556.460 Novobiocin.

(a) [Reserved]

(b) Tolerances. The tolerances for novobiocin are:

(1) Cattle. (i) Edible tissues (excluding milk): 1 ppm.

(ii) Milk: 0.1 ppm.

(2) Chickens, turkeys, and ducks. Edible tissues (excluding eggs): 1 ppm.

Sec. 556.470 Nystatin.

(a) [Reserved]

(b) Tolerances. The tolerances for nystatin are:

(1) Cattle. Edible tissues (excluding milk): Zero.

(2) Chickens and turkeys. Edible tissues: Zero.

Sec. 556.490 Ormetoprim.

(a) [Reserved]

(b) Tolerances. The tolerances for ormetoprim are:

(1) Chickens, turkeys, ducks, and chukar partridges. Edible tissues (excluding eggs): 0.1 ppm.

(2) Salmonids and catfish. Edible tissues: 0.1 ppm.

Sec. 556.495 Oxfendazole.

(a) Acceptable daily intake (ADI). The ADI for total residue of oxfendazole is 7 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for fenbendazole (marker residue) is:

(1) Cattle. Liver (target tissue): 0.8 ppm.

(2) [Reserved]

Sec. 556.500 Oxytetracycline.

(a) Acceptable daily intake (ADI). The ADI for total tetracycline residues (chlortetracycline, oxytetracycline, and tetracycline) is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for the sum of tetracycline residues are:

(1) Cattle. (i) Muscle: 2 ppm.

(ii) Liver: 6 ppm.

(iii) Fat and kidney: 12 ppm.

(iv) Milk: 0.3 ppm.

(2) Chickens and turkeys. (i) Muscle: 2 ppm.

(ii) Liver: 6 ppm.

(iii) Fat and kidney: 12 ppm.

(3) Finfish. Muscle (with adhering skin when edible): 2 ppm.

(4) Lobster. Muscle: 2 ppm.

(5) Swine and sheep. (i) Muscle: 2 ppm.

(ii) Liver: 6 ppm.

(iii) Fat and kidney: 12 ppm.

(6) Honey. 750 ppb.

(c) Related conditions of use. See §§ 520.1660c, 520.1660d, 520.1664, 522.1660a, 522.1660b, 522.1662, 522.1664, 529.1660, 558.450, and 558.455 of this chapter.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020; 88 FR 16549, Mar. 20, 2023, 88 FR 55567, Aug. 16, 2023]

Sec. 556.510 Penicillin.

(a) [Reserved]

(b) Tolerances. The tolerances for penicillin are:

(1) Cattle. (i) Edible tissues (excluding milk): 0.05 ppm.

(ii) Milk: Zero.

(2) Chickens. Edible tissues: Zero.

(3) Pheasants and quail. Edible tissues: Zero.

(4) Sheep and swine. Edible tissues: Zero.

(5) Turkeys. Edible tissues (excluding eggs): 0.01 ppm.

(c) Related conditions of use. See §§ 520.1696a, 522.1696a, 522.1696b, 526.1696, 526.1697, and 526.1698 of this chapter.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020; 86 FR 13188, Mar. 8, 2021]

Sec. 556.515 Pirlimycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of pirlimycin is 0.01 mg/kg of body weight per day.

(b) Tolerances. The tolerances for pirlimycin (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 0.5 ppm.

(ii) Muscle: 0.3 ppm.

(iii) Milk: 0.4 ppm.

(2) [Reserved]

Sec. 556.517 Poloxalene.

(a) [Reserved]

(b) Tolerances. The tolerance for poloxalene is:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 86 FR 14821, Mar. 19, 2021]

Sec. 556.540 Progesterone.

(a) [Reserved]

(b) Residues. Residues of progesterone are not permitted in excess of the following increments above the concentrations of progesterone naturally present in untreated animals:

(1) Cattle and sheep. (i) Muscle: 5 ppb.

(ii) Liver: 15 ppb.

(iii) Kidney: 30 ppb.

(iv) Fat: 30 ppb.

(2) [Reserved]

Sec. 556.560 Pyrantel.

(a) [Reserved]

(b) Tolerances. The tolerances for pyrantel are:

(1) Swine. (i) Liver and kidney: 10 ppm.

(ii) Muscle: 1 ppm.

(2) [Reserved]

Sec. 556.570 Ractopamine.

(a) Acceptable daily intake (ADI). The ADI for total residue of ractopamine hydrochloride is 1.25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for ractopamine (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 0.09 ppm.

(ii) Muscle: 0.03 ppm.

(2) Swine. (i) Liver (target tissue): 0.15 ppm.

(ii) Muscle: 0.05 ppm.

(3) Turkeys. (i) Liver (target tissue): 0.45 ppm.

(ii) Muscle: 0.1 ppm.

Sec. 556.580 Robenidine.

(a) [Reserved]

(b) Tolerances. The tolerances for robenidine are:

(1) Chickens. (i) Skin and fat: 0.2 ppm.

(ii) Other edible tissues (excluding eggs): 0.1 ppm.

(2) [Reserved]

Sec. 556.592 Salinomycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of salinomycin is 5 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for salinomycin are:

(1) Chickens. Edible tissues (excluding eggs): Not required.

(2) Quail. Edible tissues (excluding eggs): Not required.

Sec. 556.597 Semduramicin.

(a) Acceptable daily intake (ADI). The ADI for total residue of semduramicin is 3 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for semduramicin are:

(1) Chickens. (i) Liver: 400 ppb.

(ii) Muscle: 130 ppb.

(2) [Reserved]

Sec. 556.600 Spectinomycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of spectinomycin is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for spectinomycin are:

(1) Cattle. (i) Kidney (target tissue): 4 ppm spectinomycin (marker residue).

(ii) Muscle: 0.25 ppm.

(2) Chickens and turkeys. Edible tissues (excluding eggs): 0.1 ppm.

(3) Swine. Edible tissues: Not required.

Sec. 556.610 Streptomycin.

(a) [Reserved]

(b) Tolerances. The tolerances for streptomycin are:

(1) Cattle and swine. (i) Kidney: 2.0 ppm.

(ii) Other edible tissues (excluding milk): 0.5 ppm.

(2) Chickens. (i) Kidney: 2.0 ppm.

(ii) Other edible tissues (excluding eggs): 0.5 ppm.

Sec. 556.625 Sulfachloropyrazine.

(a) [Reserved]

(b) Tolerances. The tolerance for sulfachloropyrazine is:

(1) Chickens. Edible tissues (excluding eggs): Zero.

(2) [Reserved]

Sec. 556.630 Sulfachlorpyridazine.

(a) [Reserved]

(b) Tolerances. The tolerances for sulfachlorpyridazine are:

(1) Cattle and swine. Edible tissues (excluding milk): 0.1 ppm.

(2) [Reserved]

Sec. 556.640 Sulfadimethoxine.

(a) [Reserved]

(b) Tolerances. The tolerances for sulfadimethoxine are:

(1) Catfish and salmonids. Edible tissues: 0.1 ppm.

(2) Cattle. (i) Edible tissues (excluding milk): 0.1 ppm.

(ii) Milk: 0.01 ppm.

(3) Chickens, turkeys, ducks, and chukar partridges. Edible tissues (excluding eggs): 0.1 ppm.

Sec. 556.650 Sulfaethoxypyridazine.

(a) [Reserved]

(b) Tolerances. The tolerances for sulfaethoxypyridazine are:

(1) Cattle. (i) Edible tissues (excluding milk): 0.1 ppm.

(ii) Milk: Zero.

(2) Swine. Edible tissues: Zero.

Sec. 556.660 Sulfamerazine.

(a) [Reserved]

(b) Tolerances. The tolerance for sulfamerazine is:

(1) Trout. Edible tissues: Zero.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.670 Sulfamethazine.

(a) [Reserved]

(b) Tolerances. The tolerances for sulfamethazine are:

(1) Cattle. Edible tissues (excluding milk): 0.1 ppm.

(2) Chickens and turkeys. Edible tissues (excluding eggs): 0.1 ppm.

(3) Swine. Edible tissues: 0.1 ppm.

(c) Related conditions of use. See §§ 520.445, 520.2218, 520.2260a, 520.2260b, 520.2260c, 520.2261a, 520.2261b, 522.2260, 558.140, and 558.630 of this chapter.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020; 86 FR 13188, Mar. 8, 2021]

Sec. 556.685 Sulfaquinoxaline.

(a) [Reserved]

(b) Tolerances. The tolerances for sulfaquinoxaline are:

(1) Cattle. Edible tissues (excluding milk): 0.1 ppm.

(2) Chickens and turkeys. Edible tissues (excluding eggs): 0.1 ppm.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.700 Sulfomyxin.

(a) [Reserved]

(b) Tolerances. The tolerances for sulfomyxin are:

(1) Chickens and turkeys. Edible tissues (excluding eggs): Zero.

(2) [Reserved]

Sec. 556.710 Testosterone.

(a) [Reserved]

(b) Residues. Residues of testosterone are not permitted in excess of the following increments above the concentrations of testosterone naturally present in untreated animals:

(1) Cattle. (i) Fat: 2.6 ppb.

(ii) Kidney: 1.9 ppb.

(iii) Liver: 1.3 ppb.

(iv) Muscle: 0.64 ppb.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 87 FR 10970, Feb. 28, 2022]

Sec. 556.720 Tetracycline.

(a) Acceptable daily intake (ADI). The ADI for total tetracycline residues (chlortetracycline, oxytetracycline, and tetracycline) is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for the sum of tetracycline residues are:

(1) Cattle and sheep. (i) Kidney and fat: 12 ppm.

(ii) Liver: 6 ppm.

(iii) Muscle: 2 ppm.

(2) Chickens and turkeys. (i) Kidney and fat: 12 ppm.

(ii) Liver: 6 ppm.

(iii) Muscle: 2 ppm.

(3) Swine. (i) Kidney and fat: 12 ppm.

(ii) Liver: 6 ppm.

(iii) Muscle: 2 ppm.

Sec. 556.730 Thiabendazole.

(a) [Reserved]

(b) Tolerances. The tolerances for thiabendazole are:

(1) Cattle - (i) Edible tissues (excluding milk): 0.1 ppm.

(ii) Milk: 0.05 ppm.

(2) [Reserved]

[88 FR 27700, May 3, 2023]

Sec. 556.732 Tiamulin.

(a) Acceptable daily intake (ADI). The ADI for total residue of tiamulin is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for 8-alpha-hydroxymutilin (marker residue) is:

(1) Swine. Liver (target tissue): 0.6 ppm.

(2) [Reserved]

Sec. 556.733 Tildipirosin.

(a) Acceptable daily intake (ADI). The ADI for total residue of tildipirosin is 50 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for tildipirosin (the marker residue) is:

(1) Cattle. (i) Liver (the target tissue): 10 ppm.

(ii) [Reserved]

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.735 Tilmicosin.

(a) Acceptable daily intake (ADI). The ADI for total residue of tilmicosin is 25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for tilmicosin (marker residue) are:

(1) Cattle. (i) Liver (target tissue): 1.2 ppm.

(ii) Muscle: 0.1 ppm.

(2) Sheep. (i) Liver (target tissue): 1.2 ppm.

(ii) Muscle: 0.1 ppm.

(3) Swine. (i) Liver (target tissue): 7.5 ppm.

(ii) Muscle: 0.1 ppm.

Sec. 556.739 Trenbolone.

(a) Acceptable daily intake (ADI). The ADI for total residue of trenbolone is 0.4 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for trenbolone is:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) [Reserved]

Sec. 556.741 Tripelennamine.

(a) [Reserved]

(b) Tolerances. The tolerances for tripelennamine are:

(1) Cattle. (i) Edible tissues (excluding milk): 200 ppb.

(ii) Milk: 20 ppb.

(2) [Reserved]

Sec. 556.745 Tulathromycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of tulathromycin is 15 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for CP-60,300 (marker residue) are:

(1) Cattle. Liver (target tissue): 5.5 ppm.

(2) Swine. Kidney (target tissue): 15 ppm.

[84 FR 32993, July 11, 2019, as amended at 86 FR 61686, Nov. 8, 2021]

Sec. 556.746 Tylosin.

(a) [Reserved]

(b) Tolerances. The tolerances for tylosin are:

(1) Cattle. (i) Liver, kidney, fat, and muscle: 0.2 ppm.

(ii) Milk: 0.05 ppm.

(2) Chickens and turkeys. (i) Liver, kidney, fat, and muscle: 0.2 ppm.

(ii) Eggs: 0.2 ppm.

(3) Swine. Liver, kidney, fat, and muscle: 0.2 ppm.

(4) Honey. 500 ppb.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.748 Tylvalosin.

(a) Acceptable daily intake (ADI). The ADI for total residues of tylvalosin is 47.7 [micro]g/kg of body weight per day.

(b) Tolerances. A tolerance for tylvalosin in edible tissues of swine is not required.

Sec. 556.750 Virginiamycin.

(a) Acceptable daily intake (ADI). The ADI for total residue of virginiamycin is 250 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for virginiamycin are:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) Chickens. Edible tissues (excluding eggs): Not required.

(3) Swine. (i) Kidney, skin, and fat: 0.4 ppm.

(ii) Liver: 0.3 ppm.

(iii) Muscle: 0.1 ppm.

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.760 Zeranol.

(a) Acceptable daily intake (ADI). The ADI for total residue of zeranol is 1.25 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerances for zeranol are:

(1) Cattle. Edible tissues (excluding milk): Not required.

(2) Sheep. Edible tissues (excluding milk): 20 ppb.

Sec. 556.765 Zilpaterol.

(a) Acceptable daily intake (ADI). The ADI for total residue of zilpaterol is 0.083 [micro]g/kg of body weight per day.

(b) Tolerances. The tolerance for zilpaterol freebase (marker residue) is:

(1) Cattle. (i) Liver (target tissue): 12 ppb.

(ii) Muscle: 10 ppb.

(2) [Reserved]

[84 FR 32993, July 11, 2019, as amended at 85 FR 18121, Apr. 1, 2020]

Sec. 556.770 Zoalene.

(a) [Reserved]

(b) Tolerances. The tolerances for zoalene and its metabolite 3-amino-5-nitro-o -toluamide are:

(1) Chickens. (i) Liver and kidney: 6 ppm.

(ii) Muscle: 3 ppm.

(iii) Fat: 2 ppm.

(2) Turkeys. Liver and muscle: 3 ppm.

Authority: 21 U.S.C. 342, 360b, 371.
Source: 84 FR 32993, July 11, 2019, unless otherwise noted.

CFR - Code of Federal Regulations Title 21

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