Researchers at the Friedman School of Nutrition Science and Policy have come under fire for a study involving feeding genetically modified food to children.
In February, a group of 32 scientists from around the world sent an open letter to the school, citing code violations and inadequate preparatory research. A Wales-based group against genetically modified food coordinated the initiative.
The study, which took place last year, studied the extent to which a genetically modified form of rice, known as Golden Rice, can be used to combat vitamin A deficiency, which may be responsible for 500,000 cases of blindness per year. Golden Rice is fortified with vitamin A.
According to the 32 scientists who signed the letter, the study violated the Nuremberg Code, a set of ethical research principles for experiments conducted on humans, because it was conducted on children between the ages of six and 10 and did not take into account risks associated with excessive vitamin A in the body.
The letter was addressed to Professor Emeritus Robert Russell, who stepped down in July as director of the Jean Mayer United States Department of Agriculture Human Nutrition Research Center on Aging. He denied that Tufts had violated any ethical boundaries.
The scientists called the use of human subjects for genetically-modified feeding experiments "completely unacceptable" and said that all of the trials should be suspended until the researchers can prove that they followed medical ethical guidelines.
Tufts issued a formal response to the letter stating that the university "fully supports its researchers and their work with Golden Rice." The statement also said that the entire study followed the necessary research procedures and received approval from internal review boards in the United States and China.
Joe Cummins, a professor emeritus of genetics at the University of Western Ontario and one of the signatories of the letter, said he would not have opposed the study if animal testing had been conducted before feeding the rice to children.
"I found it rather outrageous in the sense that the children were brought into the study prior to the use of experimental animals," Cummins told the Daily. "That seems backwards to me. ... It shouldn't really be a jump directly from the crop to the children without adequate testing."
Russell said that animal testing would have been "meaningless" because animals break down beta-carotene, the precursor to vitamin A, in a much different way than humans do, making the study of the animal process inapplicable to the human case.
Humans do not directly digest vitamin A but rather produce it as a result of the metabolizing of beta-carotene. The precursor is present in many vegetables naturally, including carrots and spinach, but these foods are not widely available for some children in the developing world, which has led to the exploration of genetically modified rice.
But Cummins explained that studies have shown that certain levels of vitamin A and its precursors can be toxic for humans.
"There are well-established studies that show that even those [foods] with vitamin A precursors can cause toxicity in people who are overexposed to them," he said, citing a particular study in Japan that resulted in vitamin A poisoning in a young girl.
The levels of beta-carotene found in the singular meal of Golden Rice fed to the students during the study, however, were ten times less than those found in a carrot, according to Russell.
Cummins also decried what he called a troubling trend of researchers feeding children genetically modified foods.
With respect to the Friedman School study, he said his main contention was that proper informed consent was never obtained.
But Russell denied that assertion.
"That's a ridiculous accusation, totally untrue," Russell told the Daily. "We underwent every single approval -- both in the U.S. and in China -- that was needed."
Russell said the researchers received approval from both country's governments as well the Food and Drug Administration and got informed consent from the parents of the children who were fed the rice. If any of the children showed a reluctance to participate, they were not required to take part in the study.
According to Russell, researchers also gave the students school supplies as a form of non-monetary compensation for their participation in the study.
Researchers observed no negative side effects, he added.
Though the official results of the study will likely be released in several months, Russell said preliminary analyses have shown high levels of bioavailability -- the degree to which the rice can be used in the body -- in some of the children's blood samples. The feeding study caused no reported allergies or adverse reactions.
Russell said the accusations from the scientific community were likely attributable to a more general negative attitude toward genetically modified foods.
"In the [United States], we have a very different attitude towards genetic modification than Europe has; we are exposed to those products and have been for a long time," he said. "These are politically motivated people, and I'm sorry that they feel these extremes."
