The outcome of last month’s controversial Johnson Vs Monsanto lawsuit left some scratching their heads, while others jumped for joy.
Dewayne Johnson, a former school caretaker suffering from non-Hodgkin’s lymphoma, filed a lawsuit against Agrochemical company Monsanto in 2016, claiming long-term exposure to their widely-used herbicide Roundup was the cause of his affliction.
A San Francisco jury ultimately ruled in Johnson’s favour, awarding him $39.2 million in compensatory damages and $250 million in punitive damages, to be paid by Monsanto.
Whilst many have lauded the successful suit as a ‘triumph over biotech’, others feel the issue is far from resolved, particularly in light of the scientific evidence, data and reportage compiled over the last four decades, which ultimately leaves the question over glyphosate’s carcinogenicity utterly unclear.
As with the recent neonicotinoid debate, many harbour concerns that ideology and personal agendas are pushing people to conclusions far before the science is there to support them – a trend that could prove costly if agrichemicals are shelved before consideration has been given to their economic value, or, to whether suitable alternatives exist.
However, before we get into that side of the debate, let’s take a brief look at the history of commercial glyphosate use and testing.
Glyphosate: a condensed history
Initially used as a descaling and chelating agent, glyphosate was discovered to have herbicidal properties in 1970 by Monsanto scientist John Franz.
Four years later, it was introduced to the commercial market under the trade name Roundup, steadily gaining popularity in U.S agriculture for it’s versatility (glyphosate is effective in killing a wide range of plants) and systemic effects, ensuring complete plant death through absorption to both roots and aerial parts.
However, it wouldn’t gain significant global traction until the mid-1990s, when the development of glyphosate-resistant (GR) crops saw the chemical’s use shoot from an estimated 56 million kilograms applied worldwide in 1994 to over 825 million kilograms two decades later.
Today, glyphosate is considered the most widely used herbicide in the world, providing an important role in national crop production for a number of countries.
Like any widely used chemical product, glyphosate has consistently been evaluated in relation to its effects on human health in the forty years since it’s introduction as a herbicide. Particular focus has centred around links to cancer, with studies undertaken by health and regulatory agencies across the world to determine the chemical’s potential as a carcinogen.
Starting in North America, three case-control studies, each investigating links to a different lymphohaematopoietic cancer, were conducted throughout the 1980s, with the results released in the early ‘90s.
Of these, the first found a “near null” association between glyphosate exposure and leukaemia among white males residing in the area, the second an “approximately null” association between glyphosate exposure and NHL (non-Hodgkin’s lymphoma) among males, and the third, investigating any Iowa farmers who had ever handled glyphosate, found a “slight non-statistically” significant odds ratio for multiple myeloma.
An additional three case-control studies were conducted in the 1980s in Nebraska, Iowa and Minnesota and Kansas. Reported use of glyphosate as well as several individual pesticides was associated with an increased risk of NHL. However, a 2005 review of the data found no association between glyphosate and NHL, with the authors noting the original case control studies were retrospective in design and therefore potentially susceptible to recall bias.
In 2001, a Canadian study investigated the potential link between NHL and glyphosate exposure in a multicentre population-based study with 517 cases and 1,506 controls among men of six Canadian provinces. The authors reported a slight, non-statistically significant increased risk for NHL from claimed glyphosate exposure, concluding that though there was not a statistically significant finding for exposure to glyphosate per se, there was a dose-response relationship.
In Sweden in 2008, a study found NHL associations with exposure to glyphosate, although a later IARC review of the study declared its results inconclusive.
The Agriculture Health Study has conducted a range of studies using a large cohort of private and commercial pesticide applicators in Ohio and North Carolina. Amongst these, a number have evaluated glyphosate in relation to human health risk.
In summary, Wayne Temple, in his “Review of the Evidence Relating to Glyphosate and Carcinogenicity”, presented to the NZ EPA, had this to say about them:
“None of the AHS cohort study analyses reported statistically significant positive findings for glyphosate exposure and total cancer or any site-specific cancer, in adults or children. In particular, the prospective AHS studies did not corroborate the positive association with NHL reported by the Swedish case-control studies. Analyses of increasing category of glyphosate exposure days and incidence of NHL produced rate ratios that were below the null value of 1.0”
Countless other studies have been undertaken investigating the carcinogenic potential of agricultural and general occupational glyphosate use since the ‘80s, but the above examples represent the fact that inconclusivity reigns across them all, which is to be expected.
It is extremely difficult for scientists to show no effect whatsoever - that is why the list of ‘possible carcinogens’ is seemingly endless – and that is also why scientists and regulators must see a conclusive result to make a determination of serious risk.
So far, across forty years of reportage and analysis, that conclusive result is yet to be found. Scientists have consistently been unable to find a significant relationship between glyphosate use and cancer.
The IARC report
Compiled in 2015, IARC Monographs Volume 112 assessed the carcinogenicity of five organophosphate insecticides and herbicides.
It was heavily relied upon by Dewayne Johnson’s lawyers during the Monsanto trial, due to its classification of glyphosate as a ‘probable carcinogen’.
However, the term, ‘probable carcinogen’ appears slightly misleading when evaluating the report.
The IARC ultimately placed glyphosate in the ‘Group 2A’ category. In the preamble to their “IARC Monographs on the Evaluation of Carcinogenic Risks to Human”, Group 2A is described as such:
“This category is used when there is limited evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals. In some cases, an agent may be classified in this category when there is inadequate evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals and strong evidence that the carcinogenesis is mediated by a mechanism that also operates on humans. Exceptionally, an agent may be classified in this category solely on the basis of limited evidence of carcinogenicity in humans.”
The IARC monograph on glyphosate concludes the former – that there is “limited evidence of carcinogenicity in humans and sufficient evidence of carcinogenicity in experimental animals”.
Effectively, this tells us that from all the data collated over the past forty years, the evidence for glyphosate’s carcinogenicity in humans is limited, isolated to a few studies, none of which are conclusive.
One may then point to the “sufficient evidence of carcinogenicity in experimental animals” as a point of concern. However, an investigation conducted by Reuters in October of last year has cast doubt on the accuracy of that aspect of the report.
Reuters found a draft section of the report to have undergone significant changes and deletions when the report went public.
An article by reporter Kate Kelland shows draft and published versions of the report, with a section in the draft edition reading, “The report from the PWG also indicated they firmly believe and unanimously concur with the original pathologist that the incidences of renal tubular-cell neoplasms in this study are not compound related…”, which in the published report is changed to the complete opposite: “The Working Group considered that this second evaluation indicated a significant increase in the incidence of rare tumours, with a dose-related trend, which could be attributed to glyphosate.”
Reuters found a total of ten similar instances where sections of the draft declaring negative conclusions about glyphosate leading to tumours were either deleted or replaced with neutral or positive ones.
The IARC has refused to comment on these changes; 16 IARC scientists were contacted by Reuters, most declined to respond, five said they could not answer questions about the draft, none were willing to say who made the changes or why.
This certainly casts a measure of doubt over the reliability of the report, even more so given that the chairman of the IARC subgroup tasked with reviewing evidence of glyphosate on animals, Charles Jameson, was an expert witness for the plaintiffs in the Monsanto trial.
Belinda Cridge, toxicologist at Otago University, says she believes the IARC to be a credible and respected organisation.
However, she was still left surprised at the Jury’s decision:
“It was a big call to say it [Roundup] contributed to Johnson’s cancer, because they can’t call that either way - can’t say it did, can’t say it didn’t.”
She also points out a couple of inherent issues with using the IARC’s report in support of the claim that glyphosate causes cancer:
“The problem with what they do is there’s no risk assessment involved. They basically look over all the data that’s been published on the issue, then look for a link when they collate all that data together. When you do that, then absolutely there looks like there might be something there, which is how they came to this ‘probably carcinogenic’ conclusion.
“But, what they don’t do, which is really important about knowing the risk, is tell you under what circumstances it might cause cancer. So, they can’t tell you when this is going to be cancerous, they just say: ‘on weight of evidence, there’s some stuff there that says it might cause cancer’. Well that’s all very good, but when? To whom? What sort of cancer? Who’s at risk? Those sorts of things they don’t go into at all.”
This is the fundamental issue with the IARC’s reportage when used to determine a matter of risk; they don’t measure risks, simply hazards.
Michelle Miller, writer for AgDaily and frequent contributor to the Genetic Literacy Project, has previously covered this topic in considerable detail.
As she explains, the IARC lists just about everything under the sun as cancer-causing, simply because they assess ‘potential cancer hazards’ rather than cancer risks.
Their website provides access to 122 exhaustive classification volumes listing everything from 'bracken fern' to salted fish and pickled vegetables as possibly carcinogenic.
Carrying the label of ‘possible carcinogen’ (or probable in the case of glyphosate) tends to mask the fact that many of these products/occupations/chemicals are extremely unlikely to actually cause cancer (in other words the risk is low) and are merely potential hazards.
The science says glyphosate fits this description, as do many farmers, including Miller herself who has this to say about her own personal use of the chemical:
“What I can say as a farmer myself is that - if you ask any of us why we use glyphosate, it is by far the safest herbicide we have ever had access to, which is a big reason why it’s so popular and available at any Home Depot or Walmart. If we wanted to boycott it, if we thought it was terrible and making us all sick, we would be the first ones to complain.”
Basically, all the IARC set out to do was determine, as Belinda Cridge said, any link between glyphosate and cancer, and in the end their ‘probable carcinogen’ classification relied on very limited evidence and inconclusive findings.
Overall, she feels there is still “a lot we need to debate about how chemicals cause some of the changes they [the IARC] were reporting.”
Ideology and science in the courtroom
The problem in this case was that ‘inconclusive’ findings and limited evidence were enough for Johnson’s lawyers.
The burden of proof required in this instance was the lowest/easiest to satisfy in the United States justice system – “fair preponderance” – which as U.S attorney Drew Kershen explains, “basically means – did the jury believe it was more likely that the fact was proven as true by the plaintiff rather than not true?”.
“When you have that lower standard of proof”, Kershen says, “in complicated cases that involve science – particularly when they involve science as related to the factual question of: did something cause a certain harm (in this case, did Roundup herbicide cause the cancer that Mr. Johnson is suffering from?) – the concern is that the jury will look at the plaintiff, who is clearly suffering from a disease (a disease we can all identify), and then look at the defendant, who is often a faceless corporation rather than a person, and they will employ sympathy. In that situation, there’s a great concern that sympathy (simply sympathy for the person that’s suffering) will outweigh the factual evidence or weigh too heavily in the factual evidence about causation.”
From that perspective it is easy to how a jury might be swayed in the favour of Johnson.
But is that the way a trial involving complex science should be resolved?
Kershen is unconvinced:
“I’m not sure a jury system is in fact an appropriate way to try and resolve these kinds of factual causations.
“The jury isn’t really determining a scientific fact, they’re delivering a jury fact. Should they be allowed to resolve complex questions that are basically a scientific fact question about causation? Is a jury system an appropriate way to decide these cases in light of lawyer advocacy? In light of the fact that juries don’t really have any background in this? I mean they really aren’t experts, they just aren’t informed enough about this kind of subject. It gives rise to the risk of a judgement like this which is quite in the face of, and contradictory to, scientific fact.”
According to Kershen, the U.S is currently in a “time of ideologically-driven lawsuits”, and indeed, several similar cases have been seen in the U.S in the past few months.
Pharmaceutical company Johnson & Johnson, for example were recently involved in a case involving 22 women and their families who alleged the company’s talc-based products, including its baby powder, contain asbestos and caused them to develop ovarian cancer.
In the end the Jury ruled in favour of the plaintiffs, awarding $550 million in compensatory damages and $4.14 billion in punitive damages to all plaintiffs.
Johnson & Johnson lawyers argued in vain that the case was based on flawed science
Much like the IARC, the Cancer Prevention Research Journal underwent an extensive analysis of multiple studies investigating the link between baby/genital powder use and ovarian cancer in 2013. Their findings were similarly inconclusive, with the final paragraph of the report reading “…more work is needed to understand how genital powders may exert a carcinogenic effect, and which constituents (e.g. talc) may be involved. Since there are few modifiable risk factors for ovarian cancer, avoidance of genital powders may be a possible strategy to reduce ovarian cancer incidence.”
Coffee sellers have also been hit with legal action relating to claimed carcinogenicity recently in the U.S.
Californian non-profit group the ‘Council for Education and Research on Toxins’ has sued several companies that make or sell coffee because it contains low levels of the chemical acrylamide (a possible carcinogen).
Despite the fact that acrylamide is present in a range of other foods (canned black olives, french fries, toast, etc.) when heated to a certain temperature, and isn’t at levels nearly high enough in coffee to increase the risk of cancer, a number of outlets, including 7-Eleven, have been made to post cancer warnings at their stores.
As mentioned previously, this illustrates the issue of identifying the hazard but not the risk. The International Food Information Council and Foundation has pointed this out, saying the law is confusing the public because it doesn’t note levels of risk, and adding that U.S. dietary guidelines say up to five cups of coffee a day can be part of a healthy diet.
Many feel the signs may do more harm than good, with Forbes writer Omri Ben-Shahar saying, “Coffee shop cancer warnings are not only useless; they are harmful…Warning people about the insignificant toxicity of coffee obscures the difference between the trivial and the truly dangerous.”
It’s important New Zealand doesn’t allow itself to be influenced by cases like these, not until the scientific evidence is there to support them. Allowing ideology and fear of ‘the chemical’ or ‘the unnatural’ to determine regulatory decisions will, again, only do more harm than good.
As Massey University weed scientist Dr. Kerry Harrington says, “It is a concern if decisions on the use of glyphosate in New Zealand hinge on the outcome of a court case in USA where a jury of ordinary members of the public had to decide about complex issues of toxicology.”
Considering glyphosate use in New Zealand
Whether New Zealand will take any action regarding glyphosate remains to be seen.
Associate Environment Minister Eugenie Sage has asked the Environmental Protection Agency to consider adding Roundup to a list of hazardous substances it is reassessing, however, comments from Dr Fiona Thomson-Carter, general manager of the EPA's hazardous substances group, suggest they were unperturbed by the Monsanto ruling:
“There is no change to the science behind our current position, which is that products containing glyphosate remain safe to use when you follow the instructions on the product's label."
Belinda Cridge says she “can’t see how the New Zealand economy would survive if we got rid of round up”, citing the complete lack of suitable, safe alternative chemicals for weed control. However, she notes, this hasn’t stopped some from proclaiming there are:
“I get a bit angry at people saying, “oh well look at all these alternatives”. I mean one of them came out and said, “let’s look at 2,4-D. 2,4-D Is agent orange!”
“Sure, there may be alternatives out there, but there needs to be some serious thought and research put in to find something that is safe and effective. People can’t simply jump up and go ‘oh my god, Roundup is terrible, let’s use something else!’ It doesn’t work that way.”
“What I’d really like New Zealander’s to take out of this is: remember you’re working with chemicals. Always know all of the safety hazards, we learn stuff all the time so if you’re dealing with chemicals take the appropriate precautions. At this stage that’s the best thing we can do.”
As is the case with neonicotinoids and bee deaths, it seems far more research and scientific discussion needs to take place before a definitive answer regarding the carcinogenic nature of glyphosate can be reached, and it’s a question with several facets to be explored.
One of those, as pointed out by Professor Ian Shaw, is the possibility of non-genotoxic carcinogenesis, which many of the studies refuting the link between glyphosate and cancer haven’t addressed.
As Cridge explains, when scientists test a chemical for carcinogenicity, they test for a change in the DNA, based on the historic scientific understanding that when a cancer forms there is a change in the DNA. However, more recent research has revealed examples where the chemical in question doesn’t directly cause damage to the DNA but can still cause cancer.
The issue is currently one of debate amongst the scientific community, Cridge says, but it is possible that despite being non-genotoxic, glyphosate could still be carcinogenic.
However, once again, she says, it’s a matter that requires substantial research and debate, and definitive answers are still far from being reached:
“There’s still a lot of fighting and working out amongst the scientists regarding how we deal with this and understand it and apply it to chemicals, and it’s going to take a good 20 or so years to figure that out.”
The same can be said for the question of how the glyphosate in roundup might be affected by its other adjuvants.
When glyphosate is tested for safety, pure glyphosate is used, which can’t simply be bought in shops. When you buy Roundup, you’re buying a solution containing only about 30% glyphosate, the rest is diluted by chemicals that carry out a variety of purposes like extending its shelf-life, stopping it clogging up your sprayers and making sure it doesn’t break down whilst being shipped.
As Cridge says, when an agency or organisation tests the carcinogenicity of Roundup, they don’t simply buy it from the nearest department store and test it. They test the individual chemical components which make it up, and they do this because the Roundup formula regularly changes.
So, that leaves the possibility that when you add all of these chemicals together they produce a completely different effect, perhaps a carcinogenic one.
These are the sorts of things that require research and time. Again, as Cridge says, we are unlikely to see conclusive results for “a good 20 years”.
The potential effects of a glyphosate ban
Over 30 countries, including New Zealand, Australia, the United States and parts of Europe and South America, have approved major herbicide-tolerant crops for food, feed and/or cultivation.
Of these, glyphosate-resistant (GR) crops are the most common, grown on a combined 206 million acres worldwide.
Glyphosate-resistant crops have influenced significant cost reduction and increased yields in agriculture, allowing, for example, a shortening of the overall cropping time of soy beans, which facilitates an additional cropping of soybeans after wheat in the same season.
Additionally, they have had significant environmental benefits; the rise of glyphosate use has resulted in a phasing out of other herbicides proven to be significantly more toxic and has also allowed countries to move away from conventional plough-based to no-tillage (NT) and reduced-tillage (RT) production systems, reducing levels of greenhouse gas emissions through reduced tractor fuel use and additional soil carbon sequestration.
According to a 2017 paper by economists Graham Brookes, Farzad Taheripour and Wallace E. Tyner, the result of these combined improvements has been an increase of worldwide farmer incomes by just under $70 billion since 1996.
“The ‘first round’ impact of a glyphosate ban”, they therefore surmise, “would be a significant annual loss of farm income gains”, with the US ($3.38 billion/soybeans and corn) Canada (Canola), and Brazil and Argentina (soybeans/corn/cotton) suffering the most, and other countries, including our own, feeling smaller but still relatively significant effects.
On top of those quantifiable economic losses, the study also lists the following, less tangible impacts to be expected:
Increases in the potential damage caused by soil-incorporated residual herbicides to crops
Loss of the management flexibility and convenience benefit many farmers obtained from a combination of the ease of use associated with glyphosate and the increased/longer time window for spraying
Higher harvesting costs
In an environmental sense, the study predicts the banning of glyphosate to result in “a net increase in the use of herbicides of 8.2 million kg of herbicide active ingredient (+1.7%)”, and a level of carbon dioxide released into the atmosphere (from higher fuel use and loss of soil carbon through degraded soil structure and erosion) equivalent to adding 1.15 million cars to roads.
Now, admittedly, these are only ‘predictions’, but, they do attest to the fact that banning/heavily regulating glyphosate in the current climate would be an illogical move, with detrimental effects not just to the economy but to the natural environment anti-chemical activists are trying to protect.
The Monsanto/Johnson trial itself has already seen a number of flow-on effects in the three weeks since its conclusion.
U.S processed food manufacturer General Mills has removed the ‘Made with 100% Natural Whole Grain Oats’ label from its Nature Valley granola bars due to the presence of glyphosate, despite it being at levels considered safe for consumption according to EWG standards. The action is part of a settlement in a lawsuit filed by ‘Beyond Pesticides, Moms Across America and the Organic Consumers Association’ just six days after the Monsanto/Johnson verdict was reached.
Additionally, Monsanto themselves are staring down the barrel of close to 8,000 lawsuits, and Bayer (who recently acquired Monsanto) have seen their stock fall more than 10%, the biggest drop in over two years.
Despite this, Bayer remain defiant, announcing plans to appeal the verdict last Monday and saying they will resist all other lawsuits sent their way.
The grounds for that appeal are yet to be determined, but it goes without saying that tough times lie ahead for the multinational pharmaceutical giants.
In conclusion, there is certainly a positive aspect to these increasingly common cases against corporate chemical producers.
Society in general is becoming more aware of the potential health risks present in everyday foods, chemical sprays, cleaning agents and medicines, which is, in turn, forcing companies to be more proactive around the health and safety of their products – undoubtedly a positive in some cases.
The 2016 EU ban on Methylisothiazolinone for use in cosmetic leave-on products, for example, was a positive move.
However, that decision was backed by a wealth of scientific research, with the European Commission's Scientific Committee on Consumer Safety, the European Environmental Contact Dermatitis Research Group, the Danish EPA, and the International Journal of Toxicology confirming the chemical had sensitizing effects which contributed to an increasing number of allergy incidences in years previous.
The same evidence must sit behind regulatory decisions on other chemicals. If not, the line between genuine corporate negligence and false accusations based on ideology and agenda will continue to blur.