A 10-year genetic modification trial has been cancelled and another put on hold after government-approved scientists admitted serious failures that risked contamination of the environment.
Just two years into a vegetable trial at Lincoln, near Christchurch, GM opponents discovered that plants that should have been destroyed had instead been left to flower, exposing their GM pollen to the environment.
Plant and Food Research, a Crown science institute, has now ended the trial after admitting possible quarantine failures, and recommended in a report that the conduct of the trial manager should be investigated.
It said a second trial on genetically modified onions had been suspended for the "foreseeable future".
Anti-GM campaigners who first exposed the breaches late last year said the admission should raise questions about all genetic modification experiments.
"The report vindicates the very real concerns of more than 900 submitters who opposed the [trial] application, with pollen escape a major concern," said Steffan Browning, of the Soil and Health Association.
"This begs the question, just how many GE brassicas flowered in the Lincoln environment throughout the last year? Extensive testing for GE contamination must be carried out in the area."
GE Free New Zealand president Claire Bleakley said: "Everyone involved in this trial should be held accountable for the breach and [Plant and Food] should lose all its permits to carry out GE trials.
"This is not an individual staff fault but shows that the attitude is rife all the way to the top."
The Plant and Food report stated: "Taking into account the serious error of judgment of the trial manager, it is recommended that Plant and Food Research apply to MAF to cancel the current operator approval relating to this work and suspend all further work under this approval."
The Environmental Risk Management Authority originally approved the trial in May 2007 to be run under strict conditions.
Genetically modified cabbage, broccoli, cauliflower and kale were being grown to try to develop natural resistance to caterpillar pests such as the cabbage white butterfly and diamondback moth.
Plant and Food spokesman Roger Bourne admitted it was an embarrassing lapse by the institute, and promised improvement. "The learning has begun and there's a lot more to go."
He said it was a bit premature to cancel the new onion trial altogether.