Systems to prevent genetically modified (GM) crops from pollinating wild relatives or becoming mixed with non-GM food are failing, says a report out this week (8 March).
The report, by GeneWatch UK and Greenpeace International, calls for an independent international commission to be set up to investigate.
Proponents of GM crops have, however, dismissed the report as cynical and alarmist.
According to the report, GM crops have been planted illegally, have 'leaked' into the environment and have become mixed with non-GM food in 39 countries over the past decade.
This is nearly double the number of countries that have allowed farmers to grow GM crops since they were first commercialised in 1996.
The report calls for an international register of such incidents to be set up under the Cartagena Protocol on Biosafety, an international agreement aimed at ensuring that GM organisms pose no threat to biodiversity.
"Without such biosafety standards, the global community will have no chance of tracing and recalling dangerous GM organisms, should this become necessary," says Benedikt Haerlin of Greenpeace International.
The report describes 113 incidents, including 88 cases of what the authors call 'contamination', when GM material unintentionally has made its way into foods or when pollen from GM crops has pollinated wild relatives.
The report also describes 17 illegal releases of GM crops. These have resulted either from field experiments — such as those on rice in China and papaya in Thailand — or from poorly controlled commercial farming, as has happened with GM soya in Brazil and GM cotton in India.
However, Val Giddings, former vice-president for food and agriculture at the US-based Biotechnology Industry Organization, says the report is a "cynical attempt to prejudice the outcome of next week's meeting of parties to the UN Convention on Biodiversity".
Essentially a review of articles in the media and scientific literature that GeneWatch UK placed in an online register, the report has uncovered cases missed by the convention's Cartagena Protocol Clearing House. Member countries are meant to inform the clearing house about any illegal transboundary movements of GM crops.
It says that cases of misidentification, poor quality control and lack of awareness of proper controls in laboratories have led to GM tomato, courgette (zucchini) and maize seeds being distributed worldwide, and meat from GM pigs entering the food chain.
Giddings says however that the report, "presents an alarmist and overstated list of largely unremarkable biological and commercial phenomena, the net negative impact on human health and the environment of which has been zero".
"The positive benefits of crops improved through biotechnology have been, by contrast, worth billions of dollars, delivering benefits to consumers, farmers, and the environment around the world," he told SciDev.Net.
The report's lead author, Sue Mayer of GeneWatch UK, says that many more cases go unreported as companies or authorities keep such information confidential.
Tilahun Zeweldu, biotechnology advisor to Uganda's Agricultural Productivity Enhancement Programme, says: "Any breach of internationally agreed protocols and national biosafety laws should be treated as an illegal act."
"This should be done not because Greenpeace asks for it, but rather as it is necessary for the safe and sustainable use of biotechnology for a better world," he adds.