Estimated reading time: 4 minutes
Lobby group demands glyphosate ban, but experts caution over-reaction.
The African Centre for Biodiversity (ACB) has requested that the minister of agriculture deregister and ban glyphosate as well as glyphosate-tolerant genetically modified (GM) crops in South Africa.
This follows independent laboratory results indicating “glyphosate contamination in maize meal, wheat flour, bread and baby cereal, with two products exceeding the legal default limit.”
Based on these results, the ACB demands:
- Deregistration and prohibition of glyphosate under The Fertilizers, Farm Feeds, Agricultural Remedies and Stock Remedies Act (Act 36 of 1947).
- Immediate restrictions on high-exposure uses such as pre-harvest desiccation and applications in public spaces.
- Public advisories, specifically regarding baby foods.
- A precautionary review of approvals for glyphosate-tolerant GM crops.
- A ban on future herbicide-tolerant GM crops.
- A national phase-out plan with support for agroecological alternatives.
“South Africans deserve clean, safe, nourishing food, not chemical residues. This is an opportunity for the minister to act decisively to protect public health,” ACB demanded in a press release.
The laboratory tested for residues of glyphosate and its primary degradation product, aminomethylphosphonic acid (AMPA).
However, industry experts say the test results for the four products are just a storm in a teacup.
Impala special maize meal
Glyphosate residues measured 0,1162 milligrams per kilogram (mg/kg) and AMPA 0,0135mg/kg. The South African maximum residue limit (MRL) for glyphosate is 2mg/kg. As AMPA is not specifically listed in the South African MRL database, the default limit of 0.01mg/kg applies.
These levels are incredibly low, says Prof Juan Vorster, associate professor at the South African Herbicide Resistance Initiative (SAHRI) in the Department of Plant and Soil Sciences of the University of Pretoria. “To exceed the no effect level (NOEL) for chronic exposure, a 70kg adult would have to consume about 258kg of maize meal daily.”
Snowflake wheat flour
Glyphosate residues of 0,0134mg/kg were slightly above the default MRL of 0.01mg/kg. AMPA levels were below 0,010mg/kg. Compared to the glyphosate MRL on maize of 2mg/kg, these levels are insignificant, Prof Vorster pointed out.
Sasko premium white bread
Trace amounts of both glyphosate and AMPA of less than 0,010mg/kg were detected.
Cerelac baby cereal
Trace glyphosate residue below 0,010mg/kg was detected, but no traces of AMPA.
Concern
The ACB argues that, although residues in wheat products were low, no wheat-specific MRL exists because no glyphosate-tolerant wheat cultivars are registered in South Africa. They suggest practices like pre-harvest desiccation my be contributing to residues.
Prof Vorster points out that the reports did not specify sample sizes, making the results difficult to interpret. “We have no idea how repeatable these results are. But even if accepted at face value, the levels that are far too low to raise concern.” He adds that tiny residues, such as those in Cerelac, cannot be confidently traced back to wheat, and that the values were so minute, it had to be rounded up.
Glyphosate crucial for agriculture
According to Prof Vorster, glyphosate is currently a critical tool for efficient food production in South Africa. A ban would be extremely detrimental to food security.
“This does not, however, mean that we should not continually keep looking for better and safer ways of producing food. Although banning glyphosate based on these results would be absurd, we should continue our research efforts to improve food production systems.”
Responsible use
Although the science around the safety of glyphosate is solid, it remains the responsibility of users and marketers of the product to use it correctly, warns Dr Gerhard Verdoorn, head of the Griffon Poison Information Centre and known for his research in organic chemistry and environmental toxicology.
“The results of these tests by the ACB are insignificant, and similar minor exceedances have been reported for more than a decade. It does, however, point to the question of responsible use.”
He warns particularly against irresponsible late-season use of glyphosate to dry crops or manage weeds just before harvest. Exceeding MRL guidelines is never acceptable, and it is the responsibility of all users to follow label directions strictly.
Dr Verdoorn advises the minister to treat the ACBs demands cautiously, arguing that they are not valid. He says the real issue lies in proper glyphosate use and that the ACB, being strongly opposed to chemicals and GM crops, risks undermining national food security. “On the other hand,” he states, “users of chemicals should not provide ammunition for radical lobby groups such as the ACB by their irresponsible use of these production tools.” – Izak Hofmeyr, Plaas Media
