10 Strategies to Minimize Risks of GMO Contamination

by James A. Riddle Organic Independents, Winona, MN

More and more consumers are looking for organic foods. It is the largest growing sector of the food industry, with growth rates of 20-25% per year for the last 12 years. The new Federal rules for organic production prohibit the use of genetically modified organisms (GMOs) in organic production. Even though organic farmers don't plant GMO seeds, crops can become contaminated by GMO pollen drift, use of contaminated seeds, and/or sloppy handling practices. Organic, transitional, and non-GMO crop farmers need to know steps they can take to minimize risks of GMO contamination. The following list outlines some strategies that farmers can employ to minimize risks.

1. Know your seeds ┤ Prior to planting, verify that non-GMO seeds will be used. Obtain statements from seed companies concerning the non-GMO status of the varieties to be planted. Have seeds tested for all applicable GMO "events". Retain copies of test results and letters from seed suppliers. Make sure not to use genetically engineered legume inoculants. (e.g. Dormal Plus is a GMO.)

2. Know your farm ┤ Know your fields and determine which have the lowest risk of GMO contamination. Select isolated fields for wind and/or insect pollinated crops (corn, canola). Know the prevailing wind direction. Establish physical buffers, such as windbreaks and hedgerows.

3. Know your neighbors ┤ Establish good lines of communication with neighbors, especially those who directly adjoin organic fields. Notify them that you are an organic farmer, and where your organic fields are located. Get to know farmers who farm adjoining fields, even if they rent the land. Post "Organic Farm" signs along field margins, where needed.

4. Know your neighbors┬ crops ┤ Gather information from neighbors, seed dealers, and farm input suppliers on the types of crops being grown in the vicinity. Know which GMO events are being planted. If neighbors are growing Bt crops, ask them to plant their "20% non-Bt refuges" in areas that adjoin organic fields, to provide some buffer protection. If possible, delay your planting dates so that your organic crops do not pollinate at the same time as GMO crops.

5. Know your equipment ┤ Know what your equipment is used for. This includes rented and borrowed equipment and equipment used by custom operators. Know how to clean all pieces of equipment, including planters, combines, wagons, trucks, etc. Clean equipment prior to use in organic fields, and keep records to document your equipment cleaning activities.

6. Know your harvest ┤ Submit samples prior to harvest for GMO testing. If contamination is likely, collect samples along a grid pattern, going from areas with the highest risk to areas with low risk. Submit the samples separately, in case part, but not all, of the field is contaminated. Make sure samples are tested for all applicable GMO events. Keep copies of test results.

7. Know your crop storage ┤ Carefully inspect storage units prior to use. Dust from GMO crops can contaminate organic crops. Thoroughly clean augers, bins, grain dryers, rotary screen cleaners, etc., especially if they might have previously been used for GMO crops.

8. Know your truckers ┤ Carefully inspect and clean trucks and trailers prior to loading with organic grain. Make sure that transport units, including overseas shipping containers, are free of grain, dust, and other foreign material. Keep records to document, including clean transportation affidavits and bills of lading.

9. Know your records ┤ Document your efforts to minimize GMO contamination. With good records, you will have a better chance of limiting losses, identifying causes of problems, and determining liability. Valid records of organic yields and sales may help establish claims for losses, should contamination occur.

10. Know your buyers ┤ Know the contract specifications under which the organic crop is being grown. Know your buyer┬s sampling and testing protocols. Know the market-driven GMO rejection levels (tolerances) for the crops grown. Communicate with buyers and organic certifying agents concerning GMO contamination issues.


Over the past 20 years, Jim Riddle has been an organic farmer, gardener, inspector, educator, policy analyst, author, and consumer. He was founding chair of the Independent Organic Inspectors Association, (IOIA), and co-author of the IFOAM/IOIA International Organic Inspection Manual. He has helped train hundreds of organic inspectors throughout the world. Jim is a member of the U.S. delegation to Codex. He chairs the Minnesota Department of Agriculture┬s Organic Advisory Task Force, and was instrumental in the passage of Minnesota┬s landmark organic certification cost-share program. Jim serves as vice-chair of the National Organic Standards Board, which advises the USDA on organic agriculture policies and regulations.