Earlier this month Swiss biotech firm Syngenta warned it had accidentally sold the illegal Bt 10 in the US for four years, resulting in about 133 million kilograms of the corn making its way into food and feeds.
Reacting to the news, the European Commission quickly issued emergency measures whereby imports of corn gluten feed and brewers grain from the US can only be placed on the EU market if they are certified to be Bt 10 free.
Helping food and feed firms to overcome the hurdle of detection, Brussels said this week that a new event specific method (initially proposed by Syngenta) for detecting Bt10 has been approved by the Joint Research Centre (JRC), Europe's reference laboratory for genetically modified organisms.
This silica gel membrane DNA extraction protocol is based on the respective protocol from the Japanese MHLW guideline for the testing of foods produced by recombinant DNA techniques.
"The polymerase chain reaction (PCR) protocol uses target-specific oligonucleotides that have been designed to amplify a 130 bp DNA sequence specific to Bt10 event," says the Commission.
A sample test uses about 1 kg of ground corn.
Between 2001 and 2004, Syngenta accidentally sold Bt 10 corn, mistaking it for the variety Bt 11, approved for food and feed use imports into the EU.
Both varieties produce a bacterial toxin that kills insects, using the same inserted gene and producing the same protein. The only difference is the location of the inserted gene, Syngenta claims.
Syngenta says it discovered the mistake for itself when it switched to a new quality control system that tests for DNA directly. Previously it had tested only for proteins, which meant the two varieties appeared identical.
Earlier this week the US department of agriculture fined Syngenta $375,000 for the slip up.
That previous testing methods failed to detect an illegal sweetcorn present in the food chain for the past four years will do little to reassure the already GM cynical European consumer.
Environmental group Greenpeace welcomed the emergency measures but warned that Europe "remains exposed to high-risk imports of illegal GMOs, in wheat, rice, soybeans and rape seed, as well as maize."
The European Commission, the executive arm of the European Union, has said it thought about 1,000 metric tons of the unauthorised strain of Bt10 corn, all grown in the US, had entered member states through animal feed, corn flour and corn oil.