Gluten Free Watchdog Position Statement on Consumer Use of the Nima Sensor to Test Food for GlutenTricia Thompson
At Gluten Free Watchdog we have been testing a wide variety of products with the Nima Sensor. It is very difficult to put the results of testing completed to date into proper context due to the lack of a published validation report on this device. One goal of our testing is to provide recommendations for consumer use of the Nima Sensor. This is proving to be impossible at this time. In the opinion of Gluten Free Watchdog the Nima Sensor was released into the marketplace prematurely. Given the current state of development of this sensor, Gluten Free Watchdog cannot support its use by the gluten-free community at this time.
A few emerging themes from the approximately 50 products tested:
- Five products testing low gluten (four labeled gluten-free, including one certified gluten-free by GFCO) with the Nima tested below the limit of detection of 1 part per million when tested with the R5 ELISA.
- Comment: These results may be true false positives (meaning there is no gluten in the sample) OR this device may have an exceedingly low limit of detection (i.e., close to zero).
- For more information on the products testing low gluten see https://www.glutenfreewatchdog.org/news/whats-to-blame-for-possible-false-positive-low-gluten-test-results-using-the-nima/
- Barley grain and barley flour tested low gluten.
- Comment: The antibody used in this device may have a low cross-reactivity to barley.
- For more test results for wheat, barley, and rye containing foods, see https://www.glutenfreewatchdog.org/news/r5-elisa-test-results-for-gluten-containing-products-testing-low-gluten-high-gluten-using-the-nima-sensor/
- Recalled gluten-free Cheerios, regular Quaker Oats, and gluten-free rice crackers placed on top of wheat-based bread crumbs all tested smile.
- Comment: The sampling methodology for this device (i.e., testing a pea-size amount from a non-homogenized sample) is not sufficient to find gluten in samples when gluten is not evenly distributed.
- For more information on using the Nima to test foods with spotty gluten contamination, see https://www.glutenfreewatchdog.org/news/using-nima-to-test-for-spotty-cross-contact-with-gluten/
- Diluting mustard containing wheat flour with water (as recommended by the Nima website for brightly/intensely colored foods) changed the test result from high gluten to low gluten.
- Comment: Diluting a sample with water decreases the part per million of gluten in the sample.
- For more information on diluting samples and the impact on test results see https://www.glutenfreewatchdog.org/news/using-nima-to-test-mustard-for-gluten-contamination/
Note: Gluten Free Watchdog is continuing to evaluate this device. We will update our position statement when warranted.