Next spring, farmers in Canada will be able to sow one of the most complicated genetically engineered plants ever designed, a futuristic type of corn containing eight foreign genes.
With so much crammed into one seed, the modified corn will be able to confer multiple benefits, such as resistance to corn borers and rootworms, two caterpillar-like pests that infest the valuable grain crop, as well as withstanding applications of glyphosate, a weed killer better known by its commercial name, Roundup.
But a controversy has arisen over the new seeds, which were approved for use last month by the Canadian Food Inspection Agency: Health Canada hasn't assessed their safety.
The health agency said in response to questions from The Globe and Mail that it didn't have to do so, because it is relying on the two companies making the seeds, agriculture giants Monsanto Co. and Dow AgroSciences LLC, to flag any safety concerns. But the companies haven't tested the seeds either, because they say they aren't required to.
The companies have checked the safety of each of the eight genes one at a time in individual corn plants, but haven't done so when they combined the foreign matter together in one seed, says Trish Jordan, a spokesperson for Monsanto Canada Inc.
"Every single one of the traits has been tested singly, and it has gone through the complete rigorous regulatory review process," Ms. Jordan said.
When the eight traits were subsequently combined into one seed through conventional breeding techniques, there was no trigger for an additional safety assessment, she said.
But the companies', and Health Canada's, position is disputed by opponents of genetically modified foods and consumer safety advocates, who say guidelines from the UN's food standards commission, Codex Alimentarius, recommend such testing, even when the novel traits are introduced through normal plant breeding.
Michael Hansen, senior scientist at Consumers Union, a U.S. advocacy group, says he's worried that combining a large number of foreign genes could lead to the creation of allergens or other deleterious substances in food that don't occur when only one gene is involved.
The government's decision to leave the safety testing to the companies is like "putting the fox in charge of the hen house," Mr. Hansen said.
Health Canada "has entirely abdicated its responsibility" for food safety, echoed Lucy Sharratt, co-ordinator of the Canadian Biotechnology Action Network, an Ottawa-based group that is critical of genetic engineering.
In its statement to The Globe, Health Canada said it approved the new corn because it didn't find anything untoward in testing conducted from 2002 to 2008 that looked at the safety of the genes two at a time.
"According to Health Canada's policy, when a company chooses to breed or cross approved genetically modified plants with other approved GM or non-GM plants, the company must inform Health Canada only if there is a change in the safety of the product," the federal agency said. "If there was a change, the company would have to provide the necessary information to Health Canada."
The issue of the safety of the new corn has wide-ranging importance because multiple foreign genes in seeds is the wave of the future in biotechnology. When genetic modification of plants began, breeders would introduce only one gene taken from a foreign source, such as a bacterium, at a time. Corn seeds now on the market have up to three foreign genes.
Ms. Jordan said the eight-gene corn, which the companies call SmartStax because numerous traits are stacked together, will be the basic platform for all Monsanto's future versions of the crop.
She said researchers are looking to add even more genes to it, including those for drought resistance, yield increases and more efficient use of nitrogen, an important plant nutrient.
The new corn isn't the sweet type eaten on the cob but is typically used for animal feed. Monsanto expects about 200,000 acres to be planted next year in Canada, mainly in Ontario, and that the crop will have enhanced yields.
Under the UN Codex guidelines, producers of genetically engineered plants, even when the producers subsequently use conventional breeding on their seeds, should provide information "to reduce the possibility that a food derived from a recombinant-DNA plant would have an unexpected, adverse effect on human health."
Health Canada says the view that further testing needs to be done on such seeds is "erroneous" because the Codex guideline doesn't explicitly mention the stacking of genetic traits as a trigger for such a review.
Mr. Hansen believes Health Canada's interpretation leaves the country open to possible trade disputes because other jurisdictions, such as Europe, could challenge the Canadian corn by citing a failure to follow the Codex guidelines.