National Residue Program Quarterly Report (January-March 2023) 

National Residue Program 

In FY 2023 Q2, nine analytical methods were used by FSIS to detect approximately 260 different 

veterinary drugs, pesticides, and environmental contaminants. Accompanying this report is an Excel 

spreadsheet. This sheet includes detailed information regarding samples taken by FSIS in both the 

residue domestic scheduled and inspector-generated sampling programs, in addition to the residue 

import sampling program results. Additionally, the excel sheet includes quarterly metals and per- and 

polyfluorinated alkyl substances (PFAS) results. Key observations are below. 

Surveillance Sampling Plan 

Specified slaughter subclasses are sampled at the time of slaughter, after a carcass has passed 

antemortem inspection. Of the 1,916 samples analyzed by FSIS (1,841 from U.S. Federal plants and 75 

from U.S. State inspected plants), 11 sample contained violative chemical residues. In total, more than 

361,000 chemical residue analyses were conducted on the 1,916 samples collected under the 

surveillance sampling plan. 

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Table 1: Summary of FY 2023 Q2 Surveillance Sampling Results 

FY 2023 Q2 summary of surveillance sampling results from FSIS inspector-collected muscle, kidney, and liver tissue from carcasses and parts is 

shown. 

Number of Samples Analyzed this Quarter Total Number of Animal Number of Non- Animal Class Samples Planned for FY Total Number of Non- Number of Category Violative Positives 2023 Samples1 Detect Samples Violative Samples Samples 

Bovine 

Beef Cows 800 239 236 2 1 

Bob Veal 400 98 90 5 3 

Dairy Cows 800 227 226 - 1 

Formula-Fed Veal 75 28 28 - -

Heifers 400 114 113 1 -

Non-Formula-Fed Veal 75 18 18 - -

Steers 400 107 107 - -

Feral Swine 75 16 16 - -

Porcine Market Swine 800 231 230 1 -

Roaster Swine 300 98 97 - 1 

Sows 800 221 220 1 -

Poultry Young Chickens 400 107 106 1 -

Young Turkeys 400 81 81 - -

Goats 300 78 78 - -

Other 

Species 

Lambs 100 27 26 - 1 

Sheep 100 27 27 - -

Siluriformes (Catfish) 200 151 146 1 4 

Egg Products 400 48 47 1 -

Quarter Total 6,825 1,916 1,892 13 11 

1 For raw product, a sample is a representative portion of a meat, poultry, or egg product collected to identify potential microbiological, chemical, or 

pathological hazards. 

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Table 2: FY 2023 Q2 Number Collected NRP Surveillance Sampling Residues by Chemical Methods 

FY 2023 Q2 number collected surveillance sampling residue sampling summary is shown reflecting the number of samples (carcasses) analyzed 

per chemical method per animal class. 

Number of Samples Analyzed per Chemical Method 

Animal 

Category 

Animal 

Class Avermectins Aminoglycosides Antifungal 

Dyes Carbadox Metals MRM1 Nitrofurans Pesticides PFAS2 

Bovine 

Beef Cows 1 237 - - 68 239 - 171 -

Bob Veal - 96 - - 40 98 - 77 -

Dairy Cows 1 226 - - 57 227 - 163 -

Formula-Fed Veal - 28 - - - 28 - 18 -

Heifers 1 113 - - 33 114 - 83 -

Non- Formula Fed Veal - 18 - - - 18 - 7 -

Steers - 107 - - 28 107 - 75 -

Feral Swine - - - - - - - 16 16 

Porcine Market Swine - 229 - - 56 230 - 167 59 

Roaster Swine - - - 98 - - - - -

Sows - 219 - - 39 220 - 173 60 

Poultry Young Chickens - 106 - - 47 107 - 45 63 

Young Turkeys - 81 - - 23 81 - 31 -

Other 

Species 

Goats 1 77 - - - 78 - 22 -

Lambs 1 27 - - - 27 - 24 -

Mature Sheep - 27 - - - 27 - 15 -

Siluriformes (Catfish) - - 132 - 132 151 18 89 31 

Egg Products - - - - - 48 - 40 -

Quarter Total 5 1,591 132 98 523 1,800 18 1,216 229 1 MRM: multiresidue method 

2 PFAS: polyfluoroalkyl substances 

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Table 3. FY 2023 Q2 Surveillance Sampling Residue Violations 

List of FY 2023 Q2 surveillance sampling residue violations, including specific compound, concentration, tolerance, and regulatory citation by 

animal class is shown. 

Animal Tolerance Level Tissue Compound Concentration Units Authority (CFR Citation) Class Value 

Liver Florfenicol 5.63 ppm 3.7 ppm 40 CFR 556.283 

Beef Cow 

Muscle Florfenicol 1.33 ppm 0.3 ppm 40 CFR 556.283 

Muscle Prednisone -- -- * Not Approved/1/ 

Bob Veal Kidney Spectinomycin -- -- 4.0 ppm 40 CFR 556.600 

Muscle Tildipirosin -- -- * Not Approved/1/ 

Dairy Cow Liver Sulfadimethoxine 0.224 ppm 0.1 ppm 40 CFR 556.640 

Lamb Muscle Moxidectin 110 ppb 50 ppb 40 CFR 556.426 

Roaster Swine Liver Carbadox 64.7 ppb 30 ppb 40 CFR 556.100 

Muscle Metronidazole -- -- * Not Approved/1/ 

Muscle Metolachlor -- -- * Not Approved/1/ 

Siluriformes Fish 

Muscle Metolachlor -- -- * Not Approved/1/ 

Muscle Acephate 0.115 ppm * Not Approved/1/ 

* Violative residue results were detected but not quantified. 

/1/Not Approved: the residue detected is not approved in that tissue for the animal class. 

ppm – parts per million (mg/kg) 

ppb – parts per billion (μg/kg) 

CFR – Code of Federal Regulations 

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Inspector-Generated Sampling Plan 

FSIS inspectors conduct inspector-generated sampling when they suspect that animals presented for 

slaughter may have violative levels of chemical residues. If an inspector suspects that there is misuse of 

drugs that cannot be detected by the KISTM test, the samples are sent directly to the laboratory for 

appropriate analysis. These samples are reported under the Inspector-Generated program. If an 

inspector suspects that there is misuse of drugs that cannot be detected by the KISTM test, the samples 

are sent directly to the laboratory for appropriate analysis. These samples are reported under the 

Collector-Generated program. 

In FY 2023 Q2, of the 29,931 Kidney Inhibition Swab (KISTM) tests conducted on animals selected by FSIS 

(Table 4), 362 samples were submitted to FSIS field laboratories for further analysis. In total, 84 chemical 

residue violations were reported in 62 samples (Table 5). Due to multiple analyses per sample 

submitted, multiple residue violations may be found in the same sample. The predominant violative 

residues in the inspector-generated samples were Desfuroylceftiofur (17), Flunixin (13), and Penicillin 

(10) which account for 20%, 15%, and 12% of total violative residues, respectively. 

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Table 4. Summary of FY 2023 Q2 Inspector-Generated Sampling (KISTM) Test and Confirmatory Tests 

FY 2023 Q2 summary of KISTM tests, number of in-plant screens with negative results, number of carcasses sent to FSIS laboratory for 

confirmation, and the number of carcasses (i.e., samples) with violations for each animal class. 

KIS TM Test 

Animal Category Animal Class Total Number of 

In-plant 

Number of In-plant 

Negative 

Number of Samples 

Analyzed in FSIS 

Number of Samples 

with Confirmed Lab 

Carcasses Carcasses Labs Violations 

Bovine 

Bison 3 3 - -

Beef Cows 2,526 2,484 32 7 

Bob Veal 2,338 2,315 22 9 

Bulls 278 268 9 3 

Dairy Cows 18,222 17,927 209 32 

Formula-fed Veal 9 7 1 -

Heavy Calves 63 63 - -

Heifers 988 969 18 2 

Non-Formula-fed Veal 172 153 19 8 

Steers 1,586 1,538 37 1 

Boar/Stag Swine 9 9 - -

Porcine Market Swine 2,090 2,082 7 -

Roaster Swine 388 387 1 -

Sows 932 924 6 -

Adult Goats 16 16 - -

Young Goats 35 35 - -

Other Species Goats 6 6 - -

Mature Sheep 81 81 - -

Lambs 189 188 1 -

Quarter Total 29,931 29,455 362 62 

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Table 5. FY 2023 Q2 Inspector-Generated Sampling Residue Violation Results by Chemical Residue and Animal Class 

FY 2023 Q2 summary of chemical residue violations reported within the inspector-generated sampling. 

Chemical Residue Beef Cow Bob Veal Bulls Dairy Cow Heavy 

Calves Heifer 

NonFormulafed Veal 

Steer 

Market 

Swine 

Quarter 

Total 

Ampicillin -- 1 -- 5 -- -- -- -- -- 6 

Ciprofloxacin -- 3 -- -- -- -- -- -- -- 3 

Desethylene -- 1 -- -- -- -- -- -- -- 1 Ciprofloxacin 

Desfuroylceftiofur 3 -- -- 13 -- 1 -- -- -- 17 

Enrofloxacin -- 3 -- -- -- -- -- -- -- 3 

Florfenicol 1 1 -- -- -- 1 -- -- -- 3 

Florfenicol Amine -- 1 -- -- -- -- -- -- -- 1 

Flunixin 3 2 1 5 -- -- 1 1 -- 13 

Gentamycin Sulfate 1 1 -- -- -- -- -- -- -- 2 

Neomycin -- 2 -- -- -- -- -- -- -- 2 

Oxytetracycline 1 -- -- -- -- -- -- -- -- 1 

Penicillin 1 -- -- 9 -- -- -- -- -- 10 

Phenylbutazone -- -- 1 -- -- -- -- -- -- 1 

Spectinomycin -- 2 -- -- -- -- -- -- -- 2 

Sulfadimethoxine -- 2 -- 2 -- -- -- -- -- 4 

Sulfamethazine 1 1 1 3 -- -- -- -- -- 6 

Sulfamethoxazole -- 2 -- -- -- -- -- -- -- 2 

Tilmicosin -- -- -- -- -- -- 7 -- -- 7 

Quarter Total 11 22 3 37 0 2 8 1 0 84 

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Table 6. Summary of FY 2023 Q2 Collected-Generated Sampling 

FY 2023 Q2 summary of suspect animal samples sent directly to FSIS laboratory (collected-generated sampling) for appropriate analysis. 

Number of Non- Number of Non-Detect Number of Violative Animal Category Animal Class Total Samples Violative Positives Samples Samples Samples 

Bovine 

Beef Cows 7 3 4 --

Bulls 1 1 -- --

Dairy Cows 10 9 -- 1 

Heifers 3 3 -- --

Non-Formula-fed 

Veal 1 1 -- --

Steers 27 24 1 2 

Porcine Market Swine 15 15 -- --

Sows 1 1 -- --

Other Young Goats 3 3 -- --

Lambs 3 3 -- --

Quarter Total 71 63 5 3 

In addition to the publication of the quarterly FY 2023 Sampling Summary NRP results, FSIS posts the details of each positive non-violative, and 

positive violative residue result associated with the NRP sampling program in a spreadsheet format on the FSIS Residue Chemistry website. 

This spreadsheet includes detailed information regarding samples collected and analyzed by FSIS under both the “scheduled” sampling and the 

“inspector-generated” sampling programs. Overall, these data indicate levels of metals in FSIS-regulated product, on average, are relatively low 

and are not likely to cause a human health concern. FSIS plans to update this spreadsheet on an ongoing basis so as to increase program 

transparency for all stakeholders. The spreadsheet includes the following data fields: sample collection and reviewed date, the project code, the 

animal class, tissue type, chemical residue name, concentration values, sample results (whether positive non-violative or positive violative), 

chemical concentration values (if any) and the CFR reference for each chemical listed. 

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Import Residue Sampling 

Imported meat, poultry, and egg products are sampled through the point-of-entry Import Reinspection Sampling Plan. This verifies that foreign 

inspection systems in exporting countries are equivalent to U.S. standards. A total of 181 samples were analyzed under this program in FY 2023 

Q2. During FY 2023 Q2, there were zero violative import samples. The results are summarized in Table 7. 

Table 7. Summary of FY 2023 Q2 Residue Sampling of Imported Products 

FY 2023 Q2 import residue samples by inspection level and production type. 

Normal Intensified/1/ 

Product Name and Project 

Code 

Analytical 

Method 

Number of 

Samples 

Analyzed 

Non-Violative 

Positives 

Samples 

Violative 

Positive 

Samples 

Number of Non-Violative 

Samples Analyzed Positive Samples Quarter 

Total 

Imported - Metals 

IMPMETALS Metals 49 -- -- -- -- 49 

Imported - Pesticide 

IMPPESTICIDE Pesticides 108 -- -- 1 -- 109 

Imported Egg Products -

Chemistry Pesticides 8 -- -- -- -- 8 

IMPRESEGG 

Imported Processed 

Products - Residue Eastern Avermectins 5 -- -- -- -- 5 

Lab IMPRESPR_EL 

Imported Processed 

Products - Residue 

Midwestern Lab Sulfonamides 11 -- -- -- -- 11 

IMPRESPR_MWL 

Quarter Total 181 0 0 1 0 182 

/1/Increased is a level of reinspection above the normal level that is directed by a FSIS management decision. Under increased reinspection, FSIS may hold, on a case-by-case basis, 

lots of imported meat, poultry, or egg products pending receipt of a laboratory analysis. If FSIS does not place the product on hold, the importer of record is still required to hold 

product tested for adulterants by FSIS and is not to allow such product to enter commerce unless and until negative results are received. Intensified is a level of reinspection that is 

implemented automatically by the Public Health Information System (PHIS) when a Type of Inspection PHIS task is reported as “Fail.” Under intensified reinspection, FSIS holds the 

sampled lot at the official import inspection establishment pending receipt of laboratory analysis. The sampled lot is not allowed to move off-site to be held. Intensified is a level of 

reinspection that is implemented automatically by the Public Health Information System (PHIS) when a Type of Inspection PHIS task is reported as “Fail.” Under intensified 

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reinspection, FSIS holds the sampled lot at the official import inspection establishment pending receipt of laboratory analysis. The sampled lot is not allowed to move off-site to be 

held. 

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