Few clues to GE corn contamination

2.45pm

The Ministry of Agriculture and Forestry says contamination of a sweetcorn crop grown at Gisborne earlier this year may have occurred in the imported seed, rather than from neighbouring crops or post-harvest mixing of corn.

MAF investigations were prompted by Sunrise Coast Ltd, of Gisborne, telling it test results conducted in Japan by a food service company had shown GE contamination of sweetcorn it had supplied for a pizza topping mix.

MAF said today testing had shown the presence of a GE corn called Bt11 at low levels -- less than one seed in 1000 -- in product from three of four fields.

Bt11 is a type of GE maize and sweetcorn modified to be insect-resistant and herbicide tolerant. It is approved for human consumption in New Zealand, but is not known to be currently grown or sold here.

MAF said it had not found contamination in corn taken from neighbouring crops which flowered at the same time as the Sunrise Coast crops.

It was also "highly unlikely" the presence of the GE variety resulted from mixing during harvest or processing of this crop, MAF said.

Testing on the seed line grown on all the four fields was negative "but the only known link between the fields is the seed sown, and therefore the possibility remains that the imported seed was the source", MAF said.

A second variety of sweetcorn was planted on one of the four Sunrise Coast fields. When MAF tested seed from the same line a positive test was obtained, but the concentration was less than 0.05 per cent (less than five seeds in 10,000) and the actual GE DNA involved could not be identified.

MAF and the Environmental Risk Management Authority had now approved the four fields for normal use. As a precautionary measure, MAF had seized for destruction all remaining seed from the original imported lines to ensure none could be planted.

MAF said officials were now reviewing testing procedures used for imported sweetcorn and maize seeds, but the protocol was already very stringent and few changes were envisaged.

- NZPA