Exploring the issue of Roundup and cancer risk

A Melbourne gardener has launched legal action against agribusiness Monsanto.
 
Michael Ogliarolo, 54, used Roundup for over 18 years in his work as a landscape gardener and was diagnosed with non-Hodgkin’s lymphoma in 2011.
 
This is the first Australian case to link cancer with glyphosate, the active ingredient in the weedkiller Roundup.
 
The lawsuit coincides with several Melbourne and Sydney councils considering a ban on Roundup and other glyphosate products.
 
What is glyphosate?
According to the makers of Roundup, Monsanto, glyphosate is the primary active ingredient in Roundup-branded herbicides.
 
The company’s website states that glyphosate specifically inhibits an enzyme essential to plant growth.
 
‘This enzyme [EPSP] is not found in humans or animals, contributing to the low risk to human and animal health when using glyphosate-based products according to label directions,’ the company states.
 
‘The presence of this enzyme in plants, but not in humans and animals, provides a basis for a specific selective toxicity to plant species.’
 
Global health authorities’ recommendations on glyphosate
In March 2015, the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) ranked glyphosate as a Group 2a carcinogen, a substance that ‘probably causes cancer’ in people.
 
That conclusion was based on its experts’ view that there was ‘sufficient evidence’ glyphosate causes cancer in experimental animals and ‘limited evidence’ it can do so in humans.
 
IARC also concluded there was ‘strong’ evidence for genotoxicity, for both ‘pure’ glyphosate and glyphosate formulations. The agency reported that ‘studies of humans exposed to different formulations in different regions at different times reported similar increases in the same type of cancer, non-Hodgkin lymphoma’.
 
Reuters reported that the Group 2a classification prompted mass litigation in the US against Monsanto.
 
But not all authorities agree on the potentially carcinogenic risks of glyphosate.
 
The US Environmental Protection Agency (EPA) released a ‘glyphosate proposed interim decision’ for public comment in April this year:
 
‘As part of this action, EPA continues to find that there are no risks to public health when glyphosate is used in accordance with its current label and that glyphosate is not a carcinogen,’ the interim decision states.

Lawsuits against Monsanto
In the largest US jury verdict to date against Bayer AG (which acquired the chemical as part of its purchase of Monsanto last year), in May this year a California jury awarded more than $2 billion to a couple who claimed Roundup weedkiller caused their cancer.
 
Gardeners Alva and Alberta Pilliod used Roundup spray to keep weeds off their driveway for more than two decades, applying it while wearing thongs, shorts and tank tops.
 
Both developed non-Hodgkin’s lymphoma.
 
Theirs was the third consecutive US jury verdict against the company in litigation over the chemical.
 
The previous two cases involved men who also used the product over many years, and both developed non-Hodgkin’s lymphoma.
 
All of these cases are expected to be appealed.
 
Meanwhile, Bayer AG faces more than 13,400 US lawsuits over the herbicide’s alleged cancer risk, Reuters reports.
 
‘Almost all those suits are being filed by gardeners, groundskeepers and other professional weed-whackers who allege their consistent, repeated use of Roundup gave them cancer,’ Business Insider noted.


The makers of the weedkiller face more than 13,400 US lawsuits over the herbicide’s alleged cancer risk. (Image: CJ Gunther​)

Australian experts’ reaction
Lin Fritschi is a Professor of Epidemiology within the School of Public Health at Curtin University. She said the fact the IARC stated there is ‘suggestive evidence’ that glyphosate causes cancer means more information is needed on the issue.
 
‘Anyone who uses glyphosate should consider whether there are other options for weed control in their circumstances,’ Professor Fritschi said.
 
‘If you do use it, then you should download the safety data sheet for that product from the internet or ask for the safety data sheet where you buy your supply. The safety information is in section 8 and is not on the bottle itself.

‘For glyphosate, the manufacturers recommend wearing eye protection, a respirator with replaceable filter, rubber gloves, and cotton overalls buttoned at the neck and wrist. 

‘A strong message from this is that labelling of pesticides in Australia needs to be improved.’
 
Professor Sanchia Aranda, CEO of Cancer Council Australia, echoed those statements, saying people should protect themselves according to best practices in occupational health, and that the Cancer Council would also like to see safety information listed on the bottle.
 
But those sentiments were not unanimous.
 
Professor Ivan Kennedy is an expert in risk assessment and environmental fate of pesticides at the University of Sydney. He said the IARC made a ‘bad mistake’ in claiming glyphosate is a probable cause of cancer.
 
‘There is no convincing evidence for this and much evidence gathered over 40 years about it as the safest herbicide known,’ he said. ‘Any replacement will be more likely to be damaging to human health.
 
‘The precise specificity for affecting plants only by a chemical inherently so safe to animals is unlikely to be repeated. I sincerely regret that the law is being used so badly in this case.’
 
Dr Joshua Mylne, an Australian Research Council Future Fellow appointed jointly to the School of Chemistry and Biochemistry and the ARC Centre of Excellence in Plant Energy Biology at the University of Western Australia, is also frustrated by this new Australian lawsuit.
 
‘Frankly, I tire of this glyphosate mania, which I hoped would stay in the USA,’ he said. ‘The silence as scientists wait for people to be sensible seems not to be working, so I will try to say something.

‘The overwhelming opinion of experts is that glyphosate is safe. People forget “the dose maketh the poison”.

‘The scary data sheets that come with herbicides are for the concentrated compound, plus all the chemicals needed to dissolve it, plus the detergents needed to allow the chemical to penetrate the leaf – the concentrate is a toxic cocktail, to be sure.

‘However, the concentration at which what’s in the bottle is applied is usually 1000 times less, or even more dilute than that. What might remain behind days or weeks after spraying might be many orders of magnitude more dilute than what it was applied at.’
 
Instead of worrying about the potential risks of Roundup, Dr Mylne believes people should focus their attention on known carcinogens.

‘Our exposure to toxins is a constant – some exposure is more noticeable than others,’ he said. ‘One of our favourite drugs, alcohol, is quite toxic and a known carcinogen, yet we pour it down our throats with vigour every weekend.
 
‘It is considered a carcinogen by Cancer Australia, as well as the IARC, who ruled that for ethanol there was “sufficient evidence [highest IARC classification of carcinogenicity]” for it causing cancer of the oral cavity, pharynx, larynx, oesophagus, colorectum, liver (hepatocellular carcinoma), and female breast.

‘I wish people would trust experts and keep some perspective. If you seriously want to lower your cancer risk, keep using Roundup and stop drinking.’
 
Bayer AG maintains, ‘Roundup does not cause non-Hodgkin’s lymphoma’, stating:
 
‘At the end of the day, whether you’re in the court of law, regulatory agencies or court of public opinion, it’s the science that should matter here,’ the company stated.

cancer risk glyphosate non-Hodgkin’s lymphoma Roundup