It's in your food - can this herbicide commonly used in SA give you cancer?

A herbicide that is believed to cause cancer is widely in use in South Africa.

And, according to organic farmer Angus McIntosh, it can be found "in every loaf of bread sold in every shop in this country" and "in all processed foods, tinned foods and ready-made meals… consumed by most people every day".

Glyphosate, the key ingredient in Roundup, a herbicide used commercially and by private homeowners, is in the spotlight after a jury in the US found that it had caused terminal cancer and that its manufacturer, Monsanto, should pay damages amounting to $289m (about R4.173bn) to former school groundskeeper Dewayne Johnson, who is dying of non-Hodgkin lymphoma believed to have been caused by his exposure to the herbicide.

Johnson's claim is one of 5 000 similar lawsuits against the company across the US, Reuters reported.

In March 2015, the International Agency for Research on Cancer (IARC), as the specialised cancer agency of the World Health Organisation (WHO), concluded that "there is limited evidence of possible carcinogenicity (causing cancer) associated with glyphosate, which could result in non-Hodgkin lymphoma in humans".

On Monday, The Independent in the UK reported that Roundup could be pulled from British shelves following the US ruling. 

A week ago, a court in Brazil suspended the use of products containing glyphosate in that country, Reuters reported.

'Most food is produced using glyphosate'

Using a boxing analogy, McIntosh told News24 "glyphosate is the Floyd Mayweather of herbicides".

McIntosh has been farming using organic methods on Spier wine farm outside Stellenbosch since 2008.

"There is no chemical that has been used more widely than glyphosate. The Johannesburg Zoo uses it to keep its paths clean, [the] Kirstenbosch Botanical Gardens uses glyphosate…"

But, more importantly, "most of the food sold in the world is produced using glyphosate", said McIntosh.

McIntosh wrote on his blog "glyphosate is sprayed on to all the grain crops that you eat or onto the food the animals that you eat, eat. Glyphosate bio-accumulates. Cooking does not kill glyphosate".

McIntosh claims some of the dangers the chemical poses to humans include that it "chelates micronutrients, damages your gut bacteria as it destroys their shikimate pathway and it damages the critical cytochrome enzymes".

It's found in food bought at SA supermarkets

Research done by Barend Koortzen for his master's in human molecular biology at the University of the Free State last year, confirmed the presence of glyphosate in a variety of foods bought at South African supermarkets.

"Studies have detected levels of up to 2.2mg/kg in HT [herbicide-tolerant] maize and 26mg/kg in HT soybean.

"Glyphosate is not removed from grain by washing, cooking or processing.

"As a result of this, glyphosate can also be detected in processed food products. It has also been found that glyphosate can be detected in animal tissue and urine after exposure to the herbicide through feed.

"Similarly, glyphosate has also been detected in the urine of humans, either as a result of occupational exposure, through diet and/or water," Koortzen found.

'Glyphosate is not regulated'

Mariam Mayet, director at The African Centre for Biosafety (ACB), told News24 that glyphosate was unregulated in terms of how much of it was present in locally produced food and imported food.

The ACB approached the government in 2016 to ask that glyphosate to be banned.

"They said they couldn't because it had been given the thumbs up by the European Food Safety Authority.

"There's been this up and down between us and government on issues such as safety, the link to [cancer], the lack of testing and scientific studies, and the possible impact of ingestion by people who eat maize and soya.

"It's an issue that government doesn't seem to want to engage in in a meaningful way," Mayet said. 

"There are many risks associated with glyphosate as it is used from nature reserves to school playgrounds. The issue is risks posed to farm workers, to the soil, to the environment in general, including water sources, and to people who eat genetically modified (GM) maize and soya."

Mayet said about 80% of maize consumed in South Africa was GM, while 100% of soya was GM.

Maize, in particular, is a staple food in South Africa. 

"Then it becomes an issue of residues in the food and the accumulation in the body."

There are therefore multiple risks to the environment and ordinary people, said Mayet, who cited research by the ACB.

Speaking to Deutche Welle (DW) last year, former researcher at the ACB, Hailee Swanby, said people who worked with the chemical often didn't wear safety gear and didn't understand the language that the instructions came in. Swanby told DW that she had seen people using their hands to mix it in open drums, storing herbicides in their kitchens and using empty containers to fetch water from the river.  

'It becomes highly toxic and causes cancer'

Professor Michael Herbst of the Cancer Association of South Africa (Cansa) told News24 that glyphosate was not toxic by itself.

"But as soon as you include glyphosate in a mixture [such as Roundup] it becomes highly toxic and it causes cancer – there is no doubt about it."

In a research paper published in December last year, authored by Herbst, Cansa recommended that:

-     The department of agriculture, forestry and fisheries re-examine the conditions of approval of glyphosate in South Africa

-      The national department of health investigate the health implications of glyphosate exposure in South Africa with a view to instituting control measures over its free availability

-     Glyphosate exposure to humans, animals and the environment be limited as far as possible 

-     The indiscriminate spraying of glyphosate on unwanted plants (eg. cannabis) in rural areas be discontinued because indiscriminate spraying results in the destruction of cultivated fields of rural inhabitants which deprive them of self-sufficiency as far as food production is concerned

-      Sufficient and adequate protective clothing and protective devices be provided to workers who may be exposed to glyphosate

-      No planting of edible crops take place on soil sprayed with glyphosate until laboratory results indicates that the soil is totally free from any glyphosate residue

-     All individuals who work with, or handle, glyphosate be informed of the potential dangers of glyphosate and be instructed on its safe handling

-     The public be informed of the classification of glyphosate by the IARC as a probable carcinogen to humans (Group 2A)

-      Additional research be conducted on the environmental and health effects of glyphosate in formulation within the South African context.

When approached for comment Monsanto SA issued the following response: "We are sympathetic to Mr Johnson and his family."

"This decision does not change the fact that more than 800 scientific studies and reviews – and conclusions by the US Environmental Protection Agency, the US National Institutes of Health and regulatory authorities around the world – support the fact that glyphosate does not cause cancer, and did not cause Mr Johnson's cancer.

"We will appeal this decision and continue to vigorously defend this product, which has a 40-year history of safe use and continues to be a vital, effective, and safe tool for farmers and others."

The South African Department of Agriculture, Forestry and Fisheries (DAFF) could not be reached for comment on Monday. 

However, in a statement dated May 2015, following the IARC's reclassification of glyphosate, the department said: "All glyphosate-based products that are registered for use in South Africa have been through a robust chemical risk assessment process. Based on current risk assessments, glyphosate poses a minimal risk to users and the general public, provided it is used according to label instructions and safety statements.

"The DAFF, however, takes the IARC's findings very seriously and will examine the data and assessment done for the IARC classification and determine whether any regulatory action is necessary."

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