Guidelines

In order to comply with the Non-GMO Project Standard, any participant with product(s) with high-risk inputs will be required to conduct GMO testing on samples of inputs and/or end products.Non-GMO Project participants may need to develop a customized sampling plan that meets the statistical confidence level required by the Non-GMO Project Standard. With guidance from a Technical Administrator and approved lab, each participant with products requiring testing should ensure that their testing plan is designed to be efficient, economical, and effective.
General principles for GMO testing
Strip test method
  • Strip tests analyze the protein expressed by the DNA. They are the only rapid, on-site method for GMO screening.
  • Strip tests may be used for an initial screen. As an example, their use can prevent the accidental mingling of a truckload of GMO beans with a bin of non-GMO beans.
  • While a producer may use strip tests as an initial screen, it is essential to have a strong identity preservation (IP) system that incorporates the more rigorous and sensitive PCR testing method at critical points in the production process.
PCR test method
  • The PCR test method can detect all commercialized GMOs in agricultural products even in extremely low concentrations. They can precisely quantify the amount of genetically modified DNA in a sample, and can detect GMO content in a wide range of processed foods.
  • PCR is the industry standard used worldwide to verify contracts, ensure regulatory compliance, and validate non-GMO claims.
  • Plant species with risk of GMO contamination: alfalfa, canola, corn, cotton, papaya, soy, squash, sugar beet, etc.
  • When testing a sample using PCR analysis, the at-risk species in the sample determines which primer(s) must be used.  For example, a canola seed sample is tested using different primers than is a soybean sample.
  • See the Real Time PCR Test Tables for examples of appropriate PCR tests for different crop species: (being updated for 2014)

 

Qualitative PCR Analysis
  • A Qualitative (yes/no) test result will show that GMOs are “Detected” or “Not detected” at the limit of detection of 0.01%.
  • If GMOs are detected, the sample can be upgraded to a Quantitative test.  If GMOs are not detected, no further testing is needed for that sample.
  • A Qualitative test is generally less expensive than a Quantitative test.
Quantitative PCR Analysis
  • A Quantitative test result will show the actual % GMO in the sample.  For example, the result might be “0.3% GMO”.
Sample type to be used for PCR testing
  • PCR testing gives the most useful information and is most cost-effective when the sample to be tested is a single-ingredient product in which the DNA is still largely intact.
  • Certain processing methods (involving heat, change in pH, etc.) may degrade the DNA in highly-processed products.
  • Examples of highly-processed products in which the DNA may be significantly degraded: lecithin, soy sauce, soy oil, dextrose, corn syrup.
  • To know the true GMO level of a highly-processed product, use this rule-of-thumb: test the input(s) from which the product was produced, and then maintain traceability to the end product. Example:  In order to know the true GMO level of a lot of soy sauce, the producer first tests the lot of soybeans or soy grits from which the soy sauce is made. The final soy sauce product may be tested as an additional step in this quality system.
  • The intention of the Non-GMO Project is to drive testing to the most efficient and critical points in the production chain, namely the consolidation of the lot of the single-ingredient product (e.g., the crop) and the seed from which it was produced.
  • Even though the emphasis of the Non-GMO Project is on testing of single-ingredient products early in the production chain, multi-ingredient and/or highly-processed products may (and likely will) be tested anywhere in the production chain by any participant or by the Project’s own surveillance testing program.
  • Variance #7 to the Non-GMO Project Standard allows for inputs to be verified as compliant with the Standard based on testing alone at any stage of the production chain if
    1. PCR testing indicates that the GMO content of the input in question is below the relevant action threshold set by the Standard; and
    2. Appropriate laboratory controls indicate that the DNA of the input is sufficiently intact to allow valid quantitative analysis by PCR.

Inputs that do not meet this criteria, and are therefore not “testable” in this manner, must be verified by lot-specific traceability back to precursors to the input that are testable.

Sampling plan for PCR testing
  • The sample sent to the laboratory should be taken in a manner that insures that it is statistically representative of the larger lot of material.
  • To comply with the Non-GMO Project Standard, sampling plans must be designed to achieve 90% confidence in quantification of GMO at the action threshold set by the Standard.
  • Technical guidance on sampling procedures can be obtained from GIPSA, ISO, GAFTA, and other international sources. The GIPSA Grain Inspection Handbook is available at this link: http://www.gipsa.usda.gov/Publications/fgis/handbooks/gihbk1_insphb.html
Recommended sample size for PCR test

Examples of recommended sample sizes for PCR testing. For technical guidance about your particular GMO testing requirements, contact the both your TA and the Non-GMO Project approved lab that is providing the appropriate testing service. This is a general purpose guide only.
Real-Time PCR Test Table for High Risk Crop Species
Minimum Sample Size for Submission *
*plan on a minimum of 2.3kg for finished feeds/pellets
Alfalfa
50g
   
Canola
100g
   
Corn (grain)
4Kg
   
Cotton
500g
   
Papaya
200g
   
Soybean (whole)
2.5Kg
   
Squash/Zuccini
1.2Kg
   
Sugar Beet
100g
   
For finished feeds/pellets
A minimum of 4Kg
   
Corn or Soy flour, grits, meal, flakes
A 100-gram sample size is usually sufficient for ground products such as flour.