Two trade organizations say a study challenging the accuracy and reliability of strip tests for detecting biotech-derived grains and oilseeds was “poorly designed” and casts doubts on an effective technology.

The study, “Performance Assessment Under Field Conditions of a Rapid Immunological Test for Transgenic Soybeans,” was published in the April 1 issue of the International Journal of Food Science and Technology.

Its authors contend that U.S. grain handlers and exporters face risks of having grain/oilseed shipments refused if they rely solely on the strip tests.

Both the American Crop Protection Association, a trade organization representing the major manufacturers, formulators, and distributors of crop protection, pest control, and biotechnology products, and the Analytical Environmental Immunochemical Consortium, an organization dedicated to establishing immunochemical methods and other bioanalytical methods as recognized analytical tools for agricultural, environmental, and biotechnology applications, say the strip tests are effective tools for detecting biotech-derived grains and oilseeds.

“We feel this study unnecessarily casts doubts on a valuable detection technology and neglects the importance of adequate testing protocols,” says Leah Porter, executive director of the ACPA's Biotechnology Committee. She says she has “serious concerns” about the study and its conclusions.

G. David Grothaus, AEIC president, says the study utilizes an inappropriate statistical approach in evaluating data and making conclusions, and fails to consider validation of all detection techniques and the importance of sample size and sampling technique.

‘Poorly-designed’

“This was a poorly-designed study,” he says. “The outcome would have been the same, no matter which detection method — protein or DNA-based — was used. It doesn't provide any meaningful information about the performance of lateral flow strip tests.”

In short, Grothaus says, “Valid tests depend on valid science.”

Grothaus and Porter say that ACPA and AEIC are working closely with commodity groups, grain handlers, marketers, and regulators on validating tests to detect biotech crops. Both groups support efforts by the USDA to establish sampling procedures to test grains and oilseeds developed through biotechnology.

The main conclusions of the study were (1) that the use of the test strips to analyze unknown samples of whole soybeans for the presence of biotech soybeans resulted in a high number of false negative and false positive responses, and (2) operator performance were primary factors influencing field performance of the test.

The AEIC analysis of the study concludes that “the experimental data generated do not support many of the conclusions as stated by the authors,” nor does it “add any substantial scientific information to the literature on biotech testing methods.

“We do believe the strip test method…is appropriate for its designated application.”

e-mail: hembree_brandon@intertec.com