Swaminathan and P.C. Kesavan’s latest piece trashing the use of GMOs is littered with scientific untruths and misrepresents the technology.
Last month, Indian journal Current Science published a thinly-veiled attack against the use of genetically modified organisms (GMOs) in agriculture. GMO researchers like me are used to such badly researched diatribes and they are usually ignored by serious scientists. However, the Current Science piece deserves extraordinary attention because one of its authors is M.S. Swaminathan.
Swaminathan is a scientific icon in India who spearheaded the Green Revolution in the ’60s and ’70s that raised agricultural productivity in the country dramatically, saving millions of lives.
It is, thus, worrisome that a scientist of his stature (and his radiation scientist co-author P.C. Kesavan) has now been taken in by the spurious claims of the anti-GMO movement.
Counter to claims
First, Swaminathan and Kesavan say that recombinant DNA technology (the foundation upon which all genetic engineering is based) involves the insertion of foreign DNA at random locations in the host organism’s genome. This is true.
However, this “random” integration does not constitute a health risk for consumers. When scientists generate new GM crops, only plants that appear to behave and grow the same as non-GMO counterparts are selected.
Furthermore, these plants are subjected to numerous safety tests prior to any public release. Even more importantly, random off-target mutations are even more common in conventional breeding techniques such as radiation mutagenesis that the authors support.
The authors then talk about L-tryptophan, a drug that was produced using genetically modified bacteria. One specific batch of this drug produced by Showa Denko (a Japanese-owned company) led to the deaths of 37 victims. The authors try to directly implicate the use of GMO bacteria in this tragic affair.
However, experts who have studied the case found that the cause was more likely to be the presence of over 60 trace contaminating chemicals present in the disease-causing batch of L-tryptophan, rather than just the act of genetic engineering.
It is wrong on the part of Swaminathan and Kesavan to try and use this tragic case as an argument against GMOs, when in reality it is a cautionary tale about the poor regulation of dietary supplements. Further, GMO microorganisms are now routinely used to produce safe and life-saving medication including, for example, the vast majority of insulin used by diabetics worldwide.
Swaminathan and Kesavan also set their sights on Bt cotton, one of the only GMO crops currently grown in India.
Peer-reviewed research by publicly-funded scientists has repeatedly shown that Bt technology (which confers insect-resistance in plants) has reduced insecticide use globally, by about 30 per cent, according to an estimate by the US Department of Agriculture.
In the Indian context, research published in the Proceedings of the National Academies of Science found that between 2002 and 2008, the adoption of Bt cotton by Indian farmers led to a 24 per cent increase in cotton yield per acre and a 50 per cent gain in farmer profits. Recently, these massive gains have seen some reversal, but only because of agronomic practices specific to Indian agriculture, rather than some inherent defect in Bt cotton (see expert opinions by scientists here).
Overall, a meta-analysis of 147 scientific publications found that GMO crops have led to reductions in pesticide use by 37 per cent worldwide, increased crop yields by 22 per cent and farmer profits by 68 per cent. A second meta-analysis of GMO corn found similar results, showing that GMO corn had 5–24 per cent greater yield and had between 26–28 per cent “lower” amounts of toxins than comparable non-GMO corn.
The authors also claim that glyphosate, an herbicide used in certain herbicide tolerant (HT) GMO crops, is carcinogenic, relying primarily on a single US court’s verdict.
Science, however, is not adjudicated by non-expert jurors deciding individual court cases, but by the collective evidence of statistically sound scientific studies. In the case of glyphosate, the verdict in question is being appealed, the US Environmental Protection Agency re-affirmed the safety of the herbicide just last year, and the chemical was re-approved for use in the EU shortly after.
This conclusion was partly based on the fact that both in 2010 and 2017, the US government-funded Agricultural Health Study, monitoring the health of nearly 89,000 Americans, found no significant link between glyphosate and cancer.
These examples are just the most glaring instances where the authors have misrepresented GMO technology. The article in its entirety is littered with far more scientific untruths than I have space to delve into.
Consistently, Swaminathan and Kesavan have relied on papers and statements by individual scientists that run against the collective weight of peer-reviewed data and in-depth assessments by respected scientific organisations such as the Royal Society (UK), the National Academy of Sciences (US), the US Food and Drug Administration and the European Food Safety Authority.
In one instance, Swaminathan and Kesavan cite an assessment of Bt Brinjal (a GMO Brinjal grown in Bangladesh) by Gilles-Éric Séralini, a researcher whose work has been repeatedly found to be deeply flawed, and has even been retracted after publication. Séralini’s work has also drawn condemnation from as many as 6 scientific academies in his home country, France.
It’s inappropriate for Kesavan and Swaminathan to cite a disgraced researcher whose views tally with their own while ignoring the scientific consensus that lies against them. Research published just earlier this year found that Bt Brinjal was about 40 per cent less damaged by insects than non-Bt Brinjal, and thus required little to no insecticide use, leading to positive returns for farmers.
This technology is still denied to our farmers who have to use up to 65 insecticide sprays in a single season to control the pests that attack their crop.
Challenges for India
Today, India’s agriculture sector is facing enormous challenges, as evinced by the recent farmer protests. The looming impact of climate change further threatens farm productivity, which has failed to keep up with our growing population.
Fortunately, Indian science (both in India and in the global Indian diaspora) has a vast breadth of agricultural and biotechnological expertise that could be harnessed to tackle these challenges. The key, however, is rational and scientifically guided regulation, and support for publicly-funded development of new technologies, including GMOs, and new genome-editing techniques like CRISPR.
During my career, I’ve encountered brilliant Indian GMO researchers who could make important contributions to our country’s agricultural economy. Former colleagues of mine — Indians working in Switzerland — have, for instance, developed micronutrient enriched GMO rice and wheat plants that could help tackle our country’s problems with iron deficiency anaemia and vitamin-A deficiency in children.
However, the current regulatory climate makes their work nearly impossible to perform in India. This needs to change, and biased academic reviews such as the one by Swaminathan and Kesavan do nothing to help solve the problem.
Devang Mehta is a post-doctoral researcher at the University of Alberta, Canada, and works with genome editing technology in plants. He obtained his PhD (with a certificate in Science & Policy) in Plant Biotechnology from the Department of Biology, ETH Zurich, Switzerland.