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Agricultural Marketing Service Room 2646-South Building Effective March 20, 2024

National Organic Program Washington, DC 20250 Page 1 of 6

NOP 2610 Sampling Instructions for Residue Testing Rev04 Authorized Distribution: Public

Instruction

Sampling Procedures for Residue Testing

1. Purpose

This document outlines the sampling procedures recommended by the National Organic Program 

(NOP) for parties conducting residue testing of organically produced agricultural products under 

the requirements at § 205.670 of the NOP regulations.

2. Scope

This instruction applies to those collecting samples on behalf of certifying agents, State officials 

representing State organic programs, and representatives of the NOP who are conducting residue 

testing of organic agricultural products.

3. Policy

Section 205.670 of the NOP regulations specifies the conditions under which responsible parties 

should conduct testing of agricultural products that will be sold, labeled, or represented as “100 

percent organic,” “organic,” or “made with organic (specified ingredients or food group(s)).” To 

meet this requirement, these parties are responsible for the collection of samples of organically 

produced agricultural products that will be tested to detect the presence of residues in violation 

of the NOP regulations as specified under § 205.105 or other applicable laws as provided for at §

205.670(g). To ensure consistency in the sampling approach used by parties conducting residue 

testing, the NOP is issuing the following instructions for the collection, sample amounts, proper 

documentation, and chain of custody for samples collected as part of meeting the residue testing 

requirements under § 205.670 of the NOP regulations. Furthermore, under § 205.504(b)(6),

certifiers must have procedures for sampling and residue testing to ensure that proper sampling is

routinely followed.

4. Procedures

4.1 When to Collect Samples

Samples should be collected under the following conditions:

• When it is suspected that a prohibited substance has been applied;

• When it is suspected that contamination from genetically modified organisms, antibiotics, 

or prohibited substances may have occurred;

• When pesticide drift may have occurred;

• To gather evidence as part of an investigation;

• As part of a surveillance sampling program; and
United States Department of Agriculture 1400 Independence Avenue SW. NOP 2610

Agricultural Marketing Service Room 2646-South Building Effective March 20, 2024

National Organic Program Washington, DC 20250 Page 2 of 6

NOP 2610 Sampling Instructions for Residue Testing Rev04 Authorized Distribution: Public

• As part of a certifier’s procedures for risk-based supply chain traceability audits, per §

205.501(b)(7).

4.2 Sample Selection

Sample collectors should collect a sample of a given organic agricultural product, selected from 

a single location in a field, bin, or pallet. A single sample analyzed for residues using sensitive 

test procedures should provide enough information to determine if residues are present. A

sample of a crop could consist of the raw agricultural commodity (RAC) or processed 

commodity from the RAC (EPA Residue Chemistry Guidelines, Table 1). Samples may also 

include the collection and testing of soil, water, waste, seeds, or plant tissue, if appropriate.

Sample collectors may choose to select samples which attempt to detect contamination where it 

is most likely to occur due to risk factors present at a given operation or a location within an 

operation. A link to recommended methods of sampling for the determination of pesticide 

residues by The Codex Alimentarius Commission (Codex) is provided in the references section

as additional guidance on sample collection.

4.3 Sample Amounts

Sample collectors should obtain sufficient sample to ensure the laboratories will have adequate 

amounts for processing and reanalysis if necessary (Table 1). The amounts shown are consistent 

with those instituted as part of the standard operating procedures (SOPs) for the USDA 

Agricultural Marketing Service (AMS) Pesticide Data Program. If collecting from multiple 

containers is needed to obtain the suggested amounts, sample collectors should confirm the

products being sampled are from the same lot.

Table 1: Suggested Sample Amounts by Commodity Type

Commodity Type Recommended Sample Amount

Most fresh fruit and vegetables

3-5 pounds (approximately 1.5-2.5 kg);

A single large melon or squash exceeding 5 

pounds (approximately 2.5 kg) is 

acceptable.

Blended commodities or those smaller than 

a strawberry

1 pound (approximately 500 g)

Berries

Cherries

Coffee beans

Dried Commodities

Flours

Grains

Herbs

Garlic

Legumes
United States Department of Agriculture 1400 Independence Avenue SW. NOP 2610

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NOP 2610 Sampling Instructions for Residue Testing Rev04 Authorized Distribution: Public

Mushrooms (small)

Nuts

Teas

Seeds

Small jars/packages (i.e. baby food sized)

Spices

All liquids and semisolid foods (e.g. juices, 

oils)

16-32 ounces (approximately 500 mL to 

1000 mL)

Canned/jarred foods

Adapted from USDA AMS Pesticide Data Program SOPs and U.S. EPA Residue Chemistry 

Guidance (as cited in references below).

For raw commodities, the portion which should be sampled is generally the whole commodity. 

Adhering soil, decomposed outer leaves, and inedible root and tuber vegetable tops should be 

excluded from the sample. In addition to the U.S. EPA Residue Chemistry Guidance, Codex has 

guidance on which portion of the commodity should be sampled and provides recommended 

sample preparation methods for the determination of residues.

4.4 Sample Documentation

Each sample should be identified by the following information:

• Certified operation name and mailing address (city/state/zip/country);

• Identification of sampling site (may include site maps or field);

• Grower and handler information (both grower and handler should identification

be included if the sample is not collected at the farm);

• Sample identification, including commodity information, variety, brand name and 

lot number (if applicable), or other identification;

• Certifier name;

• Collector's name and signature; and

• Date collected and date shipped.

Note: The certified operation must also receive documentation (i.e., a receipt) when a sample is 

obtained for analysis.

Upon arrival at the laboratory, the following information should be recorded by the laboratory 

and included with the sample results:

• Date received;

• Name or initials of person receiving the sample;

• Explanation for what happened to a sample that is not analyzed (e.g., chain of 

custody breached, rotten sample, sample miscoded); and

• Internal Sample ID: The laboratory should generate an internal Sample ID.
United States Department of Agriculture 1400 Independence Avenue SW. NOP 2610

Agricultural Marketing Service Room 2646-South Building Effective March 20, 2024

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NOP 2610 Sampling Instructions for Residue Testing Rev04 Authorized Distribution: Public

Figure 1 below shows an example of a sample information collection worksheet that could be 

used or adopted for the purposes of proper sample documentation. 

4.5 Maintaining Chain of Custody and Sample Integrity

The chain of custody ensures the chronological possession of samples from the sample collector 

to the shipping carrier to the laboratory. Each sample shall be packed by the sample collector 

using precautions to prevent sample contamination from commingling or contact with prohibited 

substances. Samples of fresh commodities must be taken using gloved hands (latex or clean 

rubber gloves) and removed from the plant or storage bins using a clean utensil. Sample 

collectors should avoid including excess dirt and foliage (as appropriate) from field samples. 

Samples should be placed into a clean plastic bag (or other receptacle required by a given 

laboratory) and sealed with tape to provide a tamper-proof seal. Samples should be initialed and 

dated by the sample collector who has bagged the sample. In addition to the initial and date, the 

outside of each sample bag should be permanently marked with a unique identification code. A 

shipping label with time and date will be acceptable as evidence of transfer to the carrier and 

delivery to the laboratory. Sample collectors should ensure that the shipping container is 

properly sealed, labeled for perishable goods, and ship the container by the appropriate means of 

transportation. Sample collectors should avoid shipping samples that will arrive during a 

weekend or holiday when laboratories are not open to receive and process the samples for 

analysis. 

Many samples will require refrigerated temperatures for shipping and should be placed in a precooled, insulated shipping container with an adequate number of frozen cold packs. If samples 

are transported away from the collection site to be packed at a later time, then the samples must 

be maintained in a cooled container until they are packed for shipment. Sufficient packing 

materials (e.g., bubble wrap) should be used to prevent movement of the item during transit. 

Fresh and frozen samples should be shipped overnight. Processed foods that are normally stored 

at room temperature (e.g., canned vegetables, peanut butter, oils, etc.) can be shipped at ambient 

temperature by ground.

There may be cases in which the shipping container will not change hands (i.e., if the sample 

collector delivers the sample to the laboratory). In these instances, it is not necessary for the 

packing box to be sealed, but sample collectors must ensure that the product is placed in a precooled insulated shipping container along with a sufficient number of frozen cold packs to ensure 

refrigerated temperatures during the time they are transporting the sample to the laboratory. 

5. References

§ 205.670 Inspection and testing of agricultural products to be sold or labeled as “100 percent 

organic,” “organic,” or “made with organic (specified ingredients or food group(s)).” 7 CFR, pt. 

205. Print. 
United States Department of Agriculture 1400 Independence Avenue SW. NOP 2610

Agricultural Marketing Service Room 2646-South Building Effective March 20, 2024

National Organic Program Washington, DC 20250 Page 5 of 6

NOP 2610 Sampling Instructions for Residue Testing Rev04 Authorized Distribution: Public

Allowed and prohibited substances, methods, and ingredients in organic production and handling 

7 CFR pt.105. Print. 

Recommended methods of sampling for the determination of pesticide residues by The Codex 

Alimentarius Commission. Web. 18 Jan. 2024. 

https://www.fao.org/fao-who-codexalimentarius/shproxy/en/?lnk=1&url=https%253A%252F%252Fworkspace.fao.org%252Fsites%252Fcodex%2

52FStandards%252FCXG%2B33-1999%252FCXG_033e.pdf 

Codex Alimentarius Commission guidance on which portion of the commodity to be sampled 

and recommended methods of sample preparation for the determination of residues. Web. 18 

Jan. 2024. https://www.fao.org/fao-who-codexalimentarius/shproxy/en/?lnk=1&url=https%253A%252F%252Fworkspace.fao.org%252Fsites%252Fcodex%2

52FStandards%252FCXG%2B41-1993%252FCXG_041e.pdf

United States. Department of Agriculture. Agricultural Marketing Service. AMS Pesticide Data 

Program Standard Operating Procedures: SOP No: PDP SAMP PROC-02. Revision 7. 

Washington, DC: United States Department of Agriculture, 2009. Print. 

United States. Environmental Protection Agency. OCSPP Harmonized Test Guidelines Series 

860 - Residue Chemistry Test Guidelines. United States Environmental Protection Agency, Aug. 

1996. Web. 21 Dec. 2010. 

Approval 

______________________________ 

Miles V. McEvoy 

Deputy Administrator 

National Organic Program 
United States Department of Agriculture 1400 Independence Avenue SW. NOP 2610

Agricultural Marketing Service Room 2646-South Building Effective March 20, 2024

National Organic Program Washington, DC 20250 Page 6 of 6

NOP 2610 Sampling Instructions for Residue Testing Rev04 Authorized Distribution: Public

Figure 1: Sample Information Worksheet

1. Sample ID Number

Certifying 

agent 

State Year Month Day Commodity Lab 

Code 

2. Commodity Information

Origin: Domestic, Imported, Unknown 

 If imported, country of origin: 

Commodity:

Claim: 100% Organic, Organic, Made with Organic, Other

3. Collection Site Information

Operation Name and location 

Facility Type: Producer/Distribution Center/Warehouse/Packing Shed 

Field

Other

 Grower Name:

Packing Company: 

Distributor/Other:

Lot number or any other identification number on packaging: 

4. Shipping Information 

Collector’s Name:

Signature: 

Ship Date: 

5. Sample Receipt in Laboratory

Date received: Received by (initials)

Based on condition upon arrival, will sample by analyzed? (Y/N)

If not analyzed, why? Rotten/Misidentified/Other (describe)