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Bottles of paraquat (R) and glyphosate (L) are displayed for sale at a gardening shop in Bangkok.
Bottles of paraquat, right, and glyphosate, left, are displayed for sale at a gardening shop in Bangkok. Photograph: Romeo Gacad/AFP via Getty Images
Bottles of paraquat, right, and glyphosate, left, are displayed for sale at a gardening shop in Bangkok. Photograph: Romeo Gacad/AFP via Getty Images

'A sip can kill': did a chemical company misrepresent data to avoid making a safer product?

This article is more than 3 years old

A former Syngenta scientist alleges lives could have been saved with tweaks to the formulation of weedkiller paraquat

Around the world, the deadly dangers of a weedkiller called paraquat are well known. When working with the highly toxic herbicide, farmers and other users take care not to splash or spill even small amounts of the product, heeding regulatory warnings that just a tiny amount – if swallowed – will kill them.

“If you ingest just three drops of paraquat you’re going to die,” said the US farmer Cameron Peirce who uses the chemical sparingly in his fields of canola and mung beans in Kansas.

Switzerland, the home base of the paraquat maker Syngenta, has banned the chemical since 1989, and it has been banned for use in the EU since 2007, because of paraquat’s deadliness.

The US Environmental Protection Agency (EPA) allows only restricted use of the pesticide in the United States by people certified and trained to apply it, such as landscapers and farmers. And the agency warns users on a government website that “one sip can kill”. Paraquat warning labels carry the symbol of death – a skull and crossbones.

Paraquat exposure is also believed by some scientists to cause Parkinson’s disease, and Syngenta is facing litigation on that issue – though it denies responsibility.

Still, many countries allow wide use of paraquat, and the toll from paraquat poisonings is estimated at well into the thousands. The low cost and high toxicity makes paraquat a popular poison for people trying to kill themselves. Syngenta says it is just one of 377 companies worldwide that have registered paraquat for sale.

But now, internal corporate documents, obtained by a US law firm and provided to the Guardian, detail how the need for a safer formulation of Syngenta’s popular Gramoxone paraquat-based product has been the subject of in-depth company discussions for decades. Years of analysis and debate over the issue are laid out in the records, as are arguments about the accuracy of data presented to regulators, and strategies to avoid regulatory bans.

The documents, which date back to 1968, show that Syngenta and its predecessor corporate entities rejected or resisted many different options for changes to the formulations of Gramoxone, due, at least in part, to a desire to protect profits. Financial concerns were cited repeatedly in the discussions about formulation changes as company officials pushed to keep Gramoxone on the market despite mounting concerns about fatalities.

The documents also show that a longtime Syngenta scientist, who left the company in April 2008 after 28 years, argued with company officials multiple times over his belief that lives could have been saved with tweaks to product formulations that he said Syngenta considered too costly to make.

That scientist, Jon Heylings, formerly the head of research and investigative toxicology at Syngenta, accuses his former employer and Syngenta’s predecessor companies of relying on data generated in the 1970s that, according to Heylings, misrepresented the amount of an additive that could potentially make Gramoxone less deadly.

Heylings told the company more of the additive was needed than was stated. But his concerns were rejected and a product he developed that he believed was safer was shelved. After first raising the issue within the company in 1990, Heylings – who now works as a contractor for Public Health England on paraquat matters – recently renewed his push for Syngenta to acknowledge his concerns.

“I am sure we all agree that falsified data should not be used on matters of human safety with Syngenta’s products,” Heylings wrote in a June 2019 email to Syngenta’s global regulatory manager.

The documents show Syngenta’s product safety team determined internally that Heylings’ allegations were not substantiated and sent him a lengthy rebuttal to his assertions.

“While we respect your opinion, we believe we have thoroughly investigated and addressed your concerns,” the global regulatory manager responded to Heylings.

Syngenta told the Guardian that Heylings’ allegations were meritless, and said the company was “absolutely committed” to ensuring its products are used safely. “Heylings is now turning to the media because his views have not been accepted by Syngenta or the regulatory bodies he approached and are not supported by modern medical science as well,” the firm said.

Heylings is now working with the environmental organization Greenpeace to publicize his accusations and alert regulators. He sent his allegations to the EPA and to the Food and Agriculture Organization of the UN (FAO).

‘Highly confidential’

At the heart of the matter is a chemical compound that induces vomiting when ingested. After introducing Gramoxone in 1962, a Syngenta predecessor called Imperial Chemical Industries (ICI) began exploring the idea of adding an emetic, as the compound is called, to its paraquat product to trigger rapid vomiting in people who ingested it. If the vomiting happened fast enough, the theory went, it possibly could rid people’s bodies of the poison before it could kill them.

The idea was not initially embraced, as seen in comments from 1970 correspondence that “a very large quantity of emetic” would be needed in the formulation, which would make it “undesirable from commercial and other points of view …” and even if added it was unlikely to “succeed in preventing fatalities”.

Faced with evidence of accidental poisonings and also intentional ingestion by people trying to kill themselves, the company continued to explore the idea, however, investigating what quantities of emetic would be required to induce vomiting fast enough to prevent death.

In a 1972 company document marked “highly confidential”, objectives were laid out for a paraquat “reduction of hazards” project. The document states the team agreed to “investigate all possible means of reducing accident hazards by formulation”, but also stated: “The team recognized that there were alternative approaches to the problem of saving lives and maintaining ‘Gramoxone’ on the market and that the introduction of safer formulations might not be the means adopted.”

By 1973, the issue was becoming urgent, according to the minutes of a meeting discussing what progress had been made on development of a safer formulation. The head of the UK Poisons Centre told company officials that it was becoming increasingly difficult for him to “champion” Gramoxone as he had done for years due to the evidence of related poisonings and deaths, and called for “something to be done in a hurry”.

The headquarters of agricultural chemical maker Syngenta in Basel, Switzerland. Photograph: Arnd Wiegmann/Reuters

Still, the company resisted adding an emetic, with one official stating that the drawback to adding an emetic to Gramoxone was “mainly one of cost and compatibility,” according to a 1974 company document.

The records show that in addition to the idea of adding an emetic, the company explored many additions to its formulations to deter people, particularly children, from ingesting paraquat, including the addition of a coloring agent to differentiate the pesticide from the appearance of tea or a soft drink, a stench to make the product smell bad, solid formulations and stronger warning language on labels.

The company’s pursuit of a safer formulation became even more urgent in the mid-1970s as regulators increasingly took note of the deadly nature of the chemical and a US distribution partner feared the United States would force the product from the market there.

After studying the emetic on monkeys, dogs and other animals, as well as a small human trial, the company eventually settled on a dose of 5mg per 10ml of Gramoxone, and research supporting that dose was submitted to regulators.

The emetic was added to paraquat formulations in various countries starting in 1977, including in Western Samoa (now Samoa), where company officials reported a “regrettably high incidence of suicides with paraquat”.

But after more than a decade of the addition of the emetic and other changes aimed at deterring ingestion, the company was still facing problems with high numbers of paraquat poisonings, according to an October 1990 internal memo. Measures that might lower deaths, such as diluting liquid formulations at least five times, would “destroy Group profit from paraquat”, the memo states.

It was in 1990 that Heylings began championing a higher level of emetic. He told company officials the data underlying the dose decision from the 1970s was deeply flawed and that the research actually reflected that it would take three times the amount of emetic to render the weedkilling products less deadly.

Yet, according to company correspondence in 1997, newer research showed that too high of a level of emetic could cause vomiting that was so violent that it could damage the gastrointestinal tract and push vomit into the lungs.

Syngenta said that the EPA and FAO have disagreed with Heylings’ conclusions and that adding more emetic could actually create more harm.

“We reject any suggestion that in developing this product Syngenta and its predecessors had any motive other than to find the most appropriate level of emetic in paraquat to best address the risk from accidental and deliberate ingestion,” the company said in a statement. “Syngenta has invested hundreds of millions of dollars in developing and commercializing safer paraquat formulations over many decades.”

And despite the risk to users, Syngenta’s paraquat product is an “essential weed-control and resistance-management tool for farmers”, the company said, adding it uses a blue dye and a stenching agent to make it safer.

The FAO said it looked into Heylings’ allegations and is finalizing a report on paraquat now, with its conclusions to be published soon. The EPA also confirmed its awareness of Heylings’ allegations, but said the agency does not require any amount of emetic in paraquat products and believes the measures that truly save lives are the warning labels and restrictions on use.

Tip of an iceberg of troubles for Syngenta

Concerns about accidental poisonings are only the tip of an iceberg of issues that have emerged about the dangers of paraquat and Syngenta’s efforts to deal with those dangers.

The lawyer who obtained the internal documents, Missouri-based litigator Steve Tillery, has been quietly amassing evidence that he says shows Syngenta not only skimped on the emetic in its formulations, but knew – and covered up – evidence that the product also causes Parkinson’s disease in long-term users such as farmers.

Syngenta denies any such evidence of a connection between their product and Parkinson’s, which is an incurable progressive nervous system disorder that limits a person’s ability to control movement, causing tremors, loss of balance and eventually often leaving victims bedridden or forced to use a wheelchair. It also denies any attempt at a cover-up.

Several scientific studies have linked paraquat to Parkinson’s, including a large study of US farmers jointly overseen by multiple government agencies. But the EPA recently completed what it called a “thorough review” of the scientific information on paraquat and Parkinson’s disease and concluded that the weight of evidence was “insufficient” to link paraquat to Parkinson’s disease.

The company’s handling of the emetic situation is illustrative of its handling of concerns about Parkinson’s disease, according to Tillery, who said he hopes to be able to introduce evidence of the emetic issue in the Parkinson’s litigation.

The first case to go to trial over the allegations against Syngenta over paraquat and Parkinson’s is scheduled for 12 April in Illinois. The trial is very likely to be delayed due to precautions related to the Covid-19 virus, however, according to a court spokesperson.

That Illinois case – Hoffman V Syngenta – is one of several pending against Syngenta alleging the company’s paraquat products cause Parkinson’s disease. Syngenta was acquired by China National Chemical Corporation (ChemChina) in 2015, giving an added international twist to the litigation.

Lawyers around the US are now seeking people who may have been exposed to paraquat and now suffer from Parkinson’s disease.

Heylings has been deposed by the US law firm, and said he would like to help in the US court case against Syngenta.

“This is important. This is human health,” he said in an interview arranged by Greenpeace. “Maybe the legal system in the US will get to the bottom of this.”

In the UK and Ireland, Samaritans can be contacted on 116 123 or email jo@samaritans.org or jo@samaritans.ie. In the US, the National Suicide Prevention Lifeline is 1-800-273-8255. In Australia, the crisis support service Lifeline is 13 11 14. Other international helplines can be found at www.befrienders.org.

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