Off-loading GM maize in South Africa

June 2019

A recent application for permission to sell and cultivate three types of GM maize in South Africa illustrates the biotech industry vision of the future Africa.

Corteva AgriScience (agricultural division of Dow DuPont) is seeking approval for three crops, all genetically transformed to tolerate 2,4-D herbicide using a gene which also confers tolerance to quizalofop herbicide.   Two of the new GM maize varieties are stacked with double genes for glyphosate herbicide tolerance (one of which seems to be an unintended mutant version of the other), and one of these is also stacked with two Bt insecticide-generating genes.  This sounds like a succession of increasingly stacked GM crops aimed at selling herbicides, with some Bt genes thrown in now and then to 'add value'.

Both 2,4-D and glyphosate have a bad reputation: 2,4-D was one of the two active ingredients of Agent Orange which had (and continues to have ) devastating health effects on the people of Vietnam caught in the crossfire of war; glyphosate is increasingly firmly linked to a whole swathe of chronic diseases [1].

Both 2,4-D and glyphosate have been linked to non-Hodgkin lymphoma (lymphatic system cancer).  The International Agency for Research on Cancer (IARC) has classified 2,4-D as a 'possible' carcinogen and glyphosate as a 'probable' carcinogen [2].

Both 2,4-D and glyphosate at doses considered safe have been shown to disturb the gut microbial balance with potentially wide-ranging health effects.

All three herbicides, 2,4-D, glyphosate and quizalofop, come with a warning of 'harmful to skin' which means harmful to the lungs of applicators if the spray is inhaled.

Since all three kill plant-life, they will all harm the environment, including the animal and microbial life that depends on the plants.

Top dog 2,4-D, in particular, is known to target the liver, kidneys and central nervous system, and has adverse effects on reproduction.  It's a volatile substance which can travel long distances and harm humans, animals, wild plants and crops far from the site of application.

Safety assessment of these GM crops, where any details can be gleaned, are industry studies based on substantial equivalence.  The African Centre for Biodiversity (ACB) points out that 'substantial equivalence' is not a risk assessment, but "an analytical exercise that compares arbitrary comparators of GM crops to any variety or composite of varieties of conventional crops such as levels of total fibre, a limited number of minerals, fat and sugar."  A large proportion of differences were found in these assessments, but they were successfully drowned out in a diversity of historical comparators. 

Although plants derived from stacked events could have fundamental differences in physiology from any of their parental varieties, such crops are, it seems, completely under the safety assessment radar.

Corteva's claims of yield protection due to weed and insect suppression are not substantiated by field trial data.  Indeed, some GM yields were significantly lower and reduced even further when sprayed with herbicides.

The ACB sums up the situation concisely: 
"Corteva has made inaccurate and misleading claims in order to promote the commercialisation of these three GM maize varieties, and thereby is making a mockery of South Africa's scientific and regulatory processes."
As countries around the world are waking up to the harm arising from pesticide use, GM crops deliberately designed for spraying with pesticides are set to fall from favour: there's a suspicion that the offending products are to be dumped on South Africa.

Besides the pesticides and the mutant gene, the glyphosate-tolerant GM maize in the mix is 'NK603', which has courted controversy for many years due to suspected health effects and tumours (for example, see [3]).  The DNA construct in NK603 includes viral promoters which have been found to have hidden multi-functional genes for suppressing cell defences against pathogens, and which are likely to generate numerous random proteins [4].

GM 2,4-D tolerant maize, 'Enlist', was created using the less common 'whiskers-mediated' transformation technique.  This uses microscopic silicon carbide 'needles' to penetrate the cell, and presumably causes random collateral damage to the DNA in the same way as micro-particle bombardment.

In an area where maize is an important staple crop, consumed by humans and animals on a daily basis, any harm from the GMO or the pesticides (including the Bt insecticides) will become significant.

The ACB says it all: "These (three GM) varieties will ... serve to increase sales of pesticides, further exposing farm workers, consumers and wildlife, consolidate corporate control of the South African already corporatized food systems, and further increase inequalities and inequities"; "GM industrial monoculture systems merely serve the purpose of producing profits for foreign multinationals." 

Join the ACB in urging "a shift away from GM industrial systems of food production based on
precautionary measures to protect human and environmental health, as well as food security for the people of South Africa".  Check out how you can support ACB actions at

[3]  GM MAIZE IS NOT SAFE TO EAT - October 2012

·         South Africa: Fierce opposition to Corteva's 2,4-D GM maize seed, GM Watch, 18.04.19
·         Objection against general release of three 2,4-D GM maize varieties, African Centre for Biodiversity, April 2019
·         Jonathan Latham and Allison Wilson,  Regulators Discover a Hidden Viral Gene in Commercial GMO Crops,, 21.01.13
·         Rod a. Herman, et al., 2010, Compositional safety of event DAS-40278-9 (AAD-1) herbicide-tolerant maize, Landes Bioscience 1:5
·         Pranjal Yadava, el al., 2017, Advances in Maize Transformation Technologies and Development of Transgenic Maize, Review, Frontiers in Plant Science 7
·         Herbicide 2,4-D disrupts microbiome at occupationally relevant dose, GM Watch 31.03.19
·         Qizing Mao, et al., 2018, The Ramazzini Institute 13-week pilot study on glyphosate and Roundup administered at human-equivalent dose to Sprague Dawley rats: effects on the microbiome, Environmental Health 17:50
·         Pengcheng Tu, et al., March 2019, Subchronic low-dose 2,4-D exposure changed plasma acylcarnitine levels and induced gut microbiome perturbations in mice, Nature
·         Opinion of the Scientific Panel on Genetically Modified Organisms on NK603 adopted on 25 November 2003, the EFSA Journal (2003) 9, 1-14

·         Event Name: NK603, and Event Name: DAS40278,

Photo: Creative Commons

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