The Green Party has called for the Government to withdraw its approval for a genetically engineered corn that is no longer being commercially-developed in Europe.
The GE corn -- created for industrial use as a stock feed with high levels of the amino acid lysine -- was gazetted two years ago as being safe for human consumption in New Zealand.
Then Food Safety Minister Annette King declined to immediately gazette Monsanto's high lysine corn, known as LY038, under the trans-Tasman Food Standards Code because it was a stock food which had been assessed as if intended for human consumption.
Monsanto asked for the corn -- engineered to add weight to pigs and poultry -- to be approved for humans by Food Standards Australia New Zealand (FSANZ) because the biotech company expected it to turn up in corn-based foods through post-harvest contamination of shipments.
New Zealand scientists expressed concern that the high levels of the amino acid lysine in LY038 corn might trigger diseases such as alzheimer's, cancer and diabetes.
Prof Heinemann, and Professor Garth Cooper, of Auckland University's school of biological sciences, said the high levels of lysine -- one of about 20 amino acids essential to mammals -- in the modified corn gave it a substantially different nutritional profile to conventional corn.
They raised concerns over "advanced glycation endproducts" (AGEs) in the cooked corn but were refused such testing by Food Standards Australia New Zealand, on the grounds that there was not enough risk.
Green Party Food Safety spokesperson Sue Kedgley said FSANZ was criticised for accepting a Monsanto study based on rats and chickens fed with raw corn when humans were more likely to eat the corn cooked.
She said the withdrawal meant the European Union has acknowledged the potential risk and was demanding further safety testing.
"I call on FSANZ to withdraw its approval for the corn, and call for further food safety tests to be conducted, as the Europeans demand," she said.
A translation of a European website, Inf'GMO, said two files related to the corn, submitted by a joint venture of Monsanto and Cargill, Renessen Europe, were withdrawn, but the company had not publicly specified the reasons.
In Christchurch, Prof Heinemann said European officials had now taken on board his views the Monsanto trials were flawed.
"They've effectively asked Monsanto to re-do all of its studies using the proper controls," he said.
Trans-Tasman food regulator Food Safety Australia New Zealand said it had talked to the Europeans: "This withdrawal is just on commercial grounds, nothing to do with safety," said spokeswoman Lydia Buchtmann.
