Genetically modified potatoes developed by Monsanto, the multinational biotech company, have been fed to sick patients in an experiment. Rats that ate similar potatoes in the research suffered reductions in the weight of their hearts and prostate glands.
Dr Michael Antoniou, reader in molecular genetics at Guy's, King's and St Thomas' School of Medicine, said use of humans was "irresponsible and totally unethical, especially when already ill subjects were enrolled. These people truly were guinea pigs." Other scientists said the trials were too short, on too few people, to give meaningful results of long-term effects.
Monsanto said the vegetables were safe, and the researchers conducting the experiment said effects on the rats were within "permissible" limits.
The experiment is described in a hitherto unpublished report by the Nutrition Institute of the Russian Academy of Medical Science, done "by agreement with Monsanto Company" in 1998.
The report says "10 patients suffering from hypertensive disease and ischemic heart disease" were fed a pound of the Russet Burbank potatoes - modified to resist Colorado beetles - every day for three weeks, and monitored.
It goes on: "A certain risk of GM food products for human health does exist, as there can be by-effects of inserted genes besides the designed ones." The report describes the patients as "volunteers" and says they liked the GM potato so much they all "expressed their intention to consume it at home".
After comparing them with 10 other patients fed conventional potatoes, the report concludes: "The genetically modified potato provided by Monsanto did not reveal toxic, mutagenic, immune modulating and allergic effects within the examined parameters of the present experiment".
It recommended the GM potatoes "can be used for human nutrition purposes in further epidemiological research". The report says the rats, tested over six months, suffered "increases of kidneys' absolute weight" when compared to ones fed conventional potatoes but that all changes were "within permissible physiological fluctuation".
But Dr Irina Ermakova, of the Russian Academy of Science, calls the GM potatoes "dangerous" for rats, adding: "On this evidence, they cannot be used in the nourishment of people".
Tony Coombs from Monsanto UK said in a statement: "Potatoes genetically improved to prevent Colorado beetle destroying the crop have already been consumed, as safely as conventional or organic ones, in North America for years."
