"The incidents have led to trade disruptions between countries with shipments of grain, cereal and other crops being blocked by importing countries and destroyed or returned to the country of origin," Food and Agriculture Organisation (FAO) said.
However, United Nations body added that at present, there is no international agreement defining or quantifying 'low level', therefore the interpretation varies from country to country.
"The GM crop in question may be authorised for commercial use or sale in one or more countries but not yet authorised in an importing country. Therefore, if the importing country detects the unauthorised crop, it may be legally obliged to reject the shipment," the survey added.
According to the findings of survey, shipments with low levels of GM crops originated mainly from the US, Canada and China, although other countries also accidentally shipped such crops. And the highest number of incidents involved linseed, rice, maize and papaya.
"...Because trade disruptions may be very costly and given the reported increase in the occurrence of these disruptions, FAO conducted this survey and is holding a technical consultation to try to start a dialogue between countries on the issue," FAO Senior Food Safety Officer Renata Clarke said.