If you have ever acted as a surrogate parent to a hamster — still highly popular as children’s pets — you might feel that anything that reduces their fertility would be welcome. Like any rodents, hamsters are short lived and highly fertile and their owners can easily end up with rather more hamsters than they need. They also tend to escape, and who can blame them; but recapturing them before they eat through all the family’s shoes can be a challenge.
So the fact that Russian researchers reported in 2010 that hamsters fed on genetically modified soy beans suffer an increase in infant mortality and a decline in fertility might seem like a blessing to hamster owners. It is not great news, though, for other creatures that consume GM food, including human beings, and recent proposals by Monsanto, the company that invented GM soy, and the giant commodity trader Cargill, to use soy as food for farmed fish have reignited a long running concerns about the environmental and health risks of GM crops.
The Russian biologist Alexey V. Surov led the hamster research at the Institute of Ecology and Evolution of the Russian Academy of Sciences and the National Association for Gene Security. His team found that the problems emerged in the third generation of animals fed a diet of Monsanto GM soy. The hamsters were slow to mature in the second generation and infertile come the third. Strange abnormalities, such as hair growing inside the mouth, also emerged.
Fertility problem in animals fed GM crops have also been observed elsewhere: researchers in Brazil found changes to the reproductive system of rats fed GM soy and a study on effects on humans found conducted at Newcastle University found that the gene inserted into GM soy could transfers into the DNA of bacteria that live in the human gut. A Russian trial on rats showed similar transgenerational drops in fertility, high infant mortality and stunted growth. A study on mice in Italy found that a GM diet affects key organs such as the liver, pancreas and testes and a study conducted by Monsanto on rats fed the company’s genetically modified maize, disclosed in 2005 only after court proceedings in Germany, found impacts on blood cells, kidneys and blood sugar consistent with a toxic reaction. A UK study on sheep, published in 2003, found that when GM maize was eaten, some of the inserted transgenes immediately moved out from the maize and ‘horizontally’ transferred into the bacteria in the mouth. One of the genes was coded for resistance to the antibiotic kanamycin and after the transfer, the sheep’s E-coli bacteria were found to be resistant to the antibiotic.
Surov warned that high pesticide levels might also have impacted the hamsters and it is perhaps still too early for hard conclusions. Hamsters are definitely not an endangered species either way, but Surov’s work added support to demands that genetically modified produce be clearly labelled, so that consumers could choose whether to buy it or not.
For many years US trade regulators argued that labelling constituted a trade barrier and threatened to bring cases in the WTO against any country that did insist on clear labelling. But last year, when the US dropped its opposition, the Codex Alimentarius Commission, comprising the world’s food safety regulatory agencies, declared that there was nothing illegal in such labelling. Individual countries can now decide how to label GM foods without fear of retaliation from the US. This decision was hailed around the world as a victory for the rights of consumers to know what they are eating and 49 countries around the world have adopted mandatory labelling of GM ingredients. Industry resistance remains strong, however, and a move to force labelling in the United States was defeated in the Senate in June this year, despite surveys that suggested that 91 per cent of Americans supported clear labelling. This controversy is far from over.