WASHINGTON, May 19 (UPI) -- A report reviewing two decades of research on genetically engineered foods -- commonly referred to as genetically modified organisms, or GMOs -- found no evidence they pose a threat to human health.
The long-expected report from the National Academy of Sciences on concerns about GMO foods failed to find evidence genetic modifications to make crops resistant to herbicides and insects pose a risk to health, though researchers note that does not mean risks do not exist.
GMOs have been controversial for the last two decades, as food production companies have altered plants and seeds to resist insect infestations, as well as herbicides, with the goal of increasing both the health and yields of crops.
The multi-year report is based on reviews of more than 900 studies of GMO foods and health in countries around the world, finding that despite concerns raised in the last several years about health risk, the science does not reflect those risks.
"Absence of evidence is not absence of effect," Dr. Fred Gould, a professor at North Carolina State University and chair of the Committee on Genetically Engineered Crops, told UPI. "We're very clear to point out that with very subtle long term health effects, it's really difficult to point out such a thing."
Gould said, however, that embracing fears of negative effects of the foods would be a poor choice because there is evidence GMO plants have been positive environmentally, and that efforts to make foods safer or more healthy can be seen as well.
Critics of GMO foods and the committee itself suggest the evaluation was tilted toward food producers and chemical companies, chief among them Monsanto, which makes the most widely used herbicide in the world, Roundup, and has engineered many of the seeds used for GMO foods.
A 2015 study pointed out the risks of GMO crops, suggesting there is no scientific consensus on the safety of GMOs based on an inadequacy of many studies that were either too small or used questionable research methods, as well as differences in interpretation of results.
"Rigorous assessment of GMO safety has been hampered by the lack of funding independent of proprietary interests," European researchers wrote in the study. "Research for the public good has been further constrained by property rights issues, and by denial of access to research material for researchers unwilling to sign contractual agreements with the developers, which confer unacceptable control over publication to the proprietary interests."
The new report echoes this concern, which Gould said is why the committee took its time reviewing previous research, why it is not definitive in its opinion and that making the report and reviews of research easily searchable was important both for the public and for other researchers.
The 20-person committee reviewed all available research, and invited the public and other organizations to contribute thoughts, concerns and research in the interest of answering myriad concerns about GMOs.
The committee found no studies on adverse health effects directly attributed to consumption of food derived from GMO crops. Studies with animals and research on the chemical composition of foods also did not suggest a higher risk to health than non-GMO foods.
The report does note, however, some evidence that insect-resistant crops benefited human health because of lower rates of insecticide poisoning connected to food.
Environmentally, the diversity of plant and insect life on farms was not reduced, and some studies indicated insect-resistant crops led to increased insect diversity. Gene flow from GMO crops to wild species was detected, but research also did not show adverse effects, although the report says long-term environmental changes were difficult to discern from the existing research.
GMO soybean, cotton and maize have had favorable agricultural results, the committee found, but outcomes differed based on pest abundance, farming practices and agricultural infrastructure.
In some locations where resistance management strategies were not observed by farmers, some target insects reached "damaging levels of resistance," and some weeds evolved resistance to glyphosate, the active ingredient in Roundup, suggesting better weed-management strategies could delay this.
The relatively neutral report -- it does not endorse, nor condemn GMO foods -- raised the ire of GMO critics even before it was released, with questions raised about the committee's makeup and conflicts of interest because some committee members were reportedly involved with previous research funded by Monsanto, Dow and other food and chemical corporations.
Food and Water Watch released a report on May 16 calling attention to possible conflicts of interest among members of the committee, suggesting research by them or the institutions they work at is funded by companies with a potential interest in the report being positive.
"We felt it was very important for readers and the public to understand this report wasn't produced by a totally independent body -- that the national research council was not living up to its stated objectives," Tim Schwab, a senior researcher at Food and Water Watch, told UPI, adding the organization "felt the structural conflicts of interest have some potential bias."
While Schwab said he does not expect Monsanto is "whispering influence in their ears," he said researchers who have spent time working with GMO foods and products could be susceptible to some type of influence based on previous research showing that when industry is involved, "it routinely leads to results that industry favors."
In the report, FWW alleges boards governing National Research Council projects have been funded by corporations with a vested interest in the results of research and that a revolving door of key staff of industry groups exerts influence on the selection of scientists and researchers.
In addition to spotlighting millions of dollars donated to the NRC, National Academy of Sciences and other organizations, the report goes so far as to include ties between researchers themselves, or the institutions they work for, and biotechnology companies or GMO advocacy groups.
According to Schwab, contributions accepted by large, land-grant universities across the country such as the University of California and University of Illinois could be exerting influence, which led to FWW requesting and receiving a meeting with the committee when it started its work.
The FWW was at the first meeting of the committee, and Gould said they raise legitimate points about individual studies and concerns about potential conflict of interest but said some appear to be a reach. He points to one member who works for The Nature Conservancy, which has accepted contributions from Monanto in the past, but called it unfair to label him pro-GMO.
"You'd think the best way to really approach this is to have a balanced committee," Schwab said, "by including many other scientists in the mainstream scientific discourse who have been critical of GMOs."
Schwab said the organization recommended several researchers it thought would be better fit for the committee, but that their suggestions were ignored.
The concern, he said, is the interpretation of science, and a report that does not effectively express the risks inherent with GMO crops or address concerns raised by the public is only to the benefit of biotechnology companies.
"These findings very much support these companies' bottom lines, and they'll be promoting them," Schwab said.
Gould said the reason the report took so long was the committee's dedication to considering not only all data and sources for research, but also factoring in politics, bias and emotion -- which is why the report, which includes examinations of studies the FWW spotlights, includes so much information and is meant to be easily accessible to the public.
While the committee had heated debates about the evaluation of individual studies and their interpretation, the report is a group effort by scientists he said are overwhelmingly anti-GMO, he said.
Gould said he invites the FWW and other groups questioning the legitimacy of the report to examine, re-evaluate and double check the work of the committee with focus on the science, which was the goal of everybody involved.