ROME – Increased global production of bioengineered crops has led to more incidents of low levels of bioengineered organisms, also known as genetically modified organisms or G.M.O.s, being detected in traded food and feed, according to the Food and Agriculture Organization of the United Nations.

Seventy-five F.A.O. member countries that responded to an F.A.O. survey reported 198 incidents of low levels of bioengineered crops mixed into non-bioengineered crops between 2002 and 2012. Of those incidents, 138 were reported between 2009 and 2012.

Shipments with low levels of bioengineered crops originated mainly from the United States, Canada and China although other countries accidentally shipped such crops. The highest number of incidents involved linseed, rice and papaya.

The F.A.O. has organized a technical consultation to discuss the survey results March 20-21 in Rome.

“The numbers of incidents are small relative to the millions of tonnes of food and feed traded every day,” said Renata Clarke, F.A.O. senior food safety officer in charge of the survey. “But because trade disruptions may be very costly and given the reported increase in the occurrence of these disruptions, F.A.O. conducted this survey and is holding a technical consultation to try to start a dialogue between countries on the issue.”

According to the F.A.O., the incidents have led to trade disruptions in which importing countries blocked shipments of grain, cereal and other crops. The shipments then were destroyed or returned to the country of origin.

The trace amounts may become mixed with non-bioengineered food and feed crops by accident during field production, according to the F.A.O. For example a field trial of a bioengineered crop may be grown near a field with a non-bioengineered crop. Other accidents may occur in processing, packing, storage and transportation.

The F.A.O. added interpretations of “low level” of bioengineered organisms varies from country to country since no international agreement defines or quantifies “low level.” Also, the bioengineered crop in question may be authorized for commercial use in one or more countries but not yet authorized in an importing country.