Biosecurity Minister Jim Anderton says the border bungle which allowed into New Zealand sweetcorn seed now suspected of being genetically modified was twice as bad as previously thought.
Mr Anderton told Green Party co-leader Jeanette Fitzsimons an estimated 4420kg of sweetcorn seed was being investigated for possible GMcontamination.
This included an extra 2620kg of possibly contaminated seed that had been identified by the Ministry of Agriculture and Forestry following further tracing in the past day, he said in Parliament.
About two-thirds of the sweetcorn seed, 3067.5kg, was planted in Hawkes Bay, Gisborne and Ashburton.
The remaining 1352.5kg of unplanted seed had been "secured".
Mr Anderton said Biosecurity NZ was consulting growers and seed producers, but it was "almost certain" that the unplanted seeds would be destroyed, and that the plants over 373.3ha on 25 properties would be removed and destroyed.
There would be a "stringent inquiry" into how the seeds were able to enter the country despite documents accompanying at least two of the consignments that showed the parent batches from which the seeds originated had GM-contaminated seed in them.
"The Ministry of Agriculture and Forestry is conducting a stringent inquiry," he said.
"There will be accountability here."
The range of contamination appeared to be between 0.1 per cent, which is one seed in 10,000, and 0.9 per cent.
Asked by Ms Fitzsimons if MAF was trying to implement its long-held preference for a threshold below which GM contamination was legal - an acceptable level of "inadvertent" contamination - Mr Anderton said seed producers claimed they had a system of control that eliminated GM contamination.
"The ministry is rather questioning of that possibility, but that is what the seed producers say," he said.
None of the crops was likely to create any long-term problem as long as the plants were removed before they set seed.
Mr Anderton said: "It is almost certain, in my view, that the seeds and the plants will be destroyed."
