The Closed Loop Knapsack Sprayer System
In recent weeks, representatives from news media organizations have reached out to Syngenta with questions about paraquat, a herbicide that has been an essential tool for farmers for more than 60 years. These questions regard the safety of the product and its use, and focus on a fundamental disagreement over claims that paraquat use causes Parkinson’s disease.
Paraquat is a herbicide that is widely used by farmers to save arduous labor, protect against invasive weeds and produce agronomically important crops like soy, corn and cotton. Paraquat helps reduce soil erosion, protects soil health and is important for use in regenerative agricultural practices – such as no- and minimum-till – that mitigate the effects of climate change. We are only one of more than 750 companies worldwide that has registered paraquat for sale.
At Syngenta, we take the safety of our products for people and the environment very seriously. We have invested tens of millions of dollars over the lifetime of Paraquat, to ensure we have a deep understanding of this herbicide and its impacts, and to enable it to be used safely.
Our own studies are just part of the more than 1,200 safety studies done globally that have been submitted to, and reviewed by, regulatory authorities around the world. Of particular note is the 2020 US Agricultural Health Study (see 10.1016/j.envres.2020.110186), which is the most comprehensive study of pesticide use and Parkinson’s disease to date, and which shows no increased risk to farmers from the use of paraquat.
Even after more than six decades of use, and extensive research by multiple organizations and scientists, scientific evidence does not support a causal link between paraquat and Parkinson’s disease. Paraquat is safe for its intended and labelled use, and this view is supported by demanding regulatory authorities like United States and Australia – following their own thorough reviews of current scientific knowledge. Syngenta rejects claims made in litigation to the contrary. Read more in our Factsheet: Parkinson’s disease and exposure to Paraquat.
Our commitment to highest standards of product stewardship have also driven significant investments to improve product formulations and safening methods that involve no direct human contact in paraquat use. Since 2014, we have trained more than 42 million farmers around the world in the safe use of our products and offer emergency medical advice round the clock worldwide. Closed transfer systems are used by farmers handling larger quantities, while closed loop knapsack sprayers have been developed for use by smallholder farmers.
We find it heartbreaking that people have been harmed through accidental or intentional ingestion of paraquat, and we empathize with the pain of those who have lost loved ones. We believe that society needs to address the root cause and focus on mental health issues, not deprive the world of important agricultural products. Read more in our Factsheet: Deliberate self harm with pesticides.
This product contributes less than 2% of total sales, and less than 2% of overall profit for Syngenta. But it is an important product to farmers in their quest to produce food for an increasingly populated world.
We have posted additional information to enable readers to draw their own conclusions.
Fact Sheet: Exports of unregistered pesticides
Paraquat FAQs
What is paraquat, and what is it used for?
Paraquat is one of the most widely used herbicide active ingredients in the U.S. and other important markets. It acts extremely quickly under a wide range of weather and climatic conditions, is effective against a broad spectrum of weeds and immediately becomes inert when it touches soil—leaving groundwater, streams and soil biodiversity intact.
Paraquat eliminates weeds while leaving the soil intact, minimizing the need for intensive tillage — which disrupts soil structure, depletes biodiversity, causes erosion and releases carbon into the atmosphere. This makes paraquat an increasingly important tool for sustainable farming.
Farmers use paraquat to protect a range of crops, including cotton, corn, soy, peanuts, fruit trees, asparagus, artichoke, watermelon and grapes.
Is Syngenta the only company that sells paraquat?
No. Syngenta accounts for around a quarter of global paraquat sales and is one of more than 750 companies worldwide that have registered paraquat for sale. Paraquat represents less than 2% of Syngenta’s total sales and less than 2% of our overall profits.
In which markets does Syngenta sell paraquat?
Syngenta currently holds authorizations to market paraquat-based formulations in five countries, including the US, Australia, New Zealand and Japan which have among the most demanding regulatory requirements globally.
What does Syngenta have to say about some critics’ claim that paraquat contributes to Parkinson’s disease?
Syngenta rejects the claims, made in pending litigation, of a causal link between paraquat and Parkinson’s disease. This claim is not supported by scientific evidence, as science-based reviews by demanding regulatory authorities have confirmed.
Two major, science-based authorities have thoroughly reviewed the experimental and human evidence. Both the Australian Pesticides and Veterinary Medicines Authority (2016) and the U.S. Environmental Protection Agency (2019) have concluded that the evidence does not support a causal relationship between farmers’ use of paraquat and Parkinson’s disease.
No peer-reviewed research publication has ever concluded that paraquat causes Parkinson’s. The largest, longest-term epidemiological study of agricultural workers and Parkinson’s disease in the U.S., the Agricultural Health Study (AHS), found no association between exposure to paraquat and Parkinson’s disease (Shrestha, 2020). In 2021, another scientist published a peer-reviewed analysis of the available literature and concluded that “[n]o author of any published review stated that it has been established that exposure to paraquat causes Parkinson’s disease, regardless of methods used and independent of funding source,” and that “[a] consensus exists in the scientific community that the available evidence does not warrant a claim that paraquat causes Parkinson’s disease.” (Weed 2021).
Syngenta has also investigated its own production workers in the UK who were known to have been exposed to paraquat at a manufacturing site and found no increased risk of Parkinson’s disease (Tomenson & Campbell, 2011 and 2021).
Similarly, humans exposed to high doses of paraquat, for example through deliberate or accidental ingestion, did not display any Parkinson’s-like symptoms during follow-up.5
What do farmers and agricultural experts have to say about paraquat?
“Paraquat is one of the essential herbicides that we use”
Tim Durham, Associate Professor of Crop Science at Ferrum College, Virginia, US and a seasonal vegetable farmer.
“Keeping our soils here intact is a must and the best way to do it is no-till. The only way we can make no-till work is to have an effective herbicide, and paraquat is definitely it”
Larry Steckel, Professor and Extension Weed Specialist at the University of Tennessee, US
“We use all the correct protective equipment – a closed loop transfer system so that operators are not exposed to the chemical, all our machinery have filters in them, we use the right nozzles.., we can see that if used carefully and appropriately, that it is safe”
Mark Fowler, a farmer and President of the Western Australia Farmers Grains Council
“If we lost access to paraquat, then we would really be in all sorts of strife”
Andrew Weidemann, a farmer and Board Member at Grain Producers Australia
“Paraquat works faster, and it has helped me increase the planting index from twice to three times a year”
Zaenal ARIFIN, a farmer in Indonesia
“It is very helpful for farmers, especially in controlling weeds at the beginning of the process before planting”
Wahyudi, a rice farmer in East Lampung, Indonesia
“Around 30 – 60 percent of the crop yield will decrease due to unmanaged weeds on agricultural land”
Professor Nanik Suryani, a researcher and professor from Lampung University, Indonesia
[When] used correctly, paraquat is a safe and effective tool for farmers to control weeds. Its importance for weed control has never been greater. By providing effective, low cost weed control, paraquat allows farmers to reduce tillage and implement other conservation practices to reduce soil erosion and improve water quality, all while providing an effective mode of action in the fight against herbicide resistant weeds.
Ensuring product stewardship through regular trainings and safe equipment
GRAMOXONE® 360 PRO leadership workshop in Australia
“I’ve learned a lot more about the safety side, there’s a lot of myths that have been dispelled.”
years
Paraquat, helping farmers tackle the most difficult weeds for > 60 years
Million
42.4 million farmers trained in the safe use of our products since 2014
$>Yield
Paraquat can increase farmer yields and annual income by up to $1,000 per ha
Millions
We have invested hundreds of millions of dollars to develop safer paraquat formulations and delivery systems
studies
1,200 paraquat studies reviewed by regulators around the world
$billion
Syngenta invests about $1.3 billion in R&D every year across crop protection and seeds