Paraquat has been a valuable tool for farmers all over the world for nearly 50 years. Its speed of action, rainfastness and now its role as a weed resistance fighter are unsurpassed.
However, paraquat’s importance and benefits go beyond simply weed control. Its unique property of being locked onto soil so tightly on contact, and the consequent biological inactivation, mean that it has become a key component in conservation tillage systems, especially no-till.
Paraquat plus reduced tillage improves soil structure and fertility, timeliness of operations, biodiversity and the overall profitability of farming. It is also unique as a non-selective herbicide in being able to be sprayed between the rows of growing crops without fear of crop damage.
In this section you can find out about the specific benefits paraquat brings on the farm, for the environment and in rural communities.
Key benefits of paraquat
On the farm For the environment In rural communities Controls weeds
Reduces [no-glossary] soil erosion
Creates opportunities
Acts fast
Increases soil organic matter
A recent study published in the Journal of Environmental Science and Health examined the impact of paraquat on earthworms. Entitled “Influence of Substrate on Bioaccumulation of C-Paraquat in Compost Worms Eisenia foetida“ the study concluded:
“That compost worms (Eisenia foetida) did not influence the dissipation of paraquat in the substrates indicates that, although paraquat is persistent, it is inactivated independently of the biological and physical activity of the worms. Paraquat, even at the highest rate of 120 μg/g substrate, did not cause any earthworm mortality, and the bioconcentration factors were small.”
Earthworms play an important role in soil health, aerating the soil and aiding in the decomposition of organic matter.
This study joins reconfirms previous research that has shown that paraquat is inactive in soil and cannot be taken up by plant roots or other organisms. It also further supports the conclusion made by scientists and regulators that normal uses of paraquat in accordance with the simple label instructions do not cause an unacceptable environmental impact.
For more information about the safety of paraquat to the environment click here.
To view the complete study publication, click here.
Conservation agriculture methods, combined with the use of herbicides, such as paraquat, can save billions of Euros according to a June 29 article in the European Voice.
Entitled “Reducing soil erosion could save billions,” the article outlined study results shared by SOWAP (SOil and WAter Protection). These results show that more than €7 billion in fuel, labor and environmental impact costs could be saved by using alternative farming methods, such as no-till farming, to reduce soil erosion.
No-till farming methods were developed to prevent soil erosion and reduce labor and fuel costs. Herbicides, such as paraquat, play a key role in the success of this no-till program.
In the article, SOWAP project director Mike Lane was quoted as saying, “It is better to produce soil with a couple of kilogrammes of herbicide per hectare than to spend seven litres of diesel per hectare to plough a field which then erodes it resulting in the loss of 200 million tones of soil per annum in the EU alone.”
Conservation agriculture in action
The answer is “yes,” according to former Greenpeace leader Patrick Moore. He acknowledges the positive impact of pesticides in a May 2006 article on The African Executive website, saying, “agricultural science and technology have changed our world for the better. Pesticides have played an important role.”
The article, entitled “How pesticides are saving the Earth,” was written in honor of International Earth Day. In it, Moore states:
“…continued research and development in genetic science, fertilizers and pesticides has enabled us to dramatically increase both the quantity and quality of food production without increasing the area of land required. The result is greater wilderness protection and a more bio-diverse world.”
The article also addresses concerns about pesticide residues in food and calls for people to “confront activist misinformation and scare tactics by remembering how much we've achieved through the science of agriculture.”
Moore is currently Chair and Chief Scientist of Greenspirit Strategies Ltd. in Vancouver, Canada. View the complete article, here.
Paraquat Helping to Save the Earth
The views expressed by Moore are consistent with the benefits shown in than 40 years of experience using paraquat.
'Sagip-Lupa' means 'save our soil' and that’s just what the Philippines’ Sagip-Lupa Soil Conservation Project is designed to do.
Soil erosion leads to depletion of nutrient content due to loss of surface soil where, unfortunately, most of the nutrients required by plants are found. Farmers in erosion-prone areas often resort to increased use of fertilizers to augment lost soil nutrients.
The Sagip-Lupa project, which began in December 2004, was created to minimize or eliminate the risk of soil erosion on Philippine farmland using paraquat for effective weed management as part of a zero-tillage system.
Collaborators on the project include regional agricultural and environmental management thought leaders, such as the University of the Philippines Los Baños.
"As a weed science expert, my philosophy is very simple: Bring technologies to the farmers. Hence, I'm very glad to be chosen as overall coordinator of the Sagip-Lupa Soil Conservation Project. This project reaches out to the grassroots level, which are the farmers, offering them technologies that address their concerns about soil erosion and effective weed management,” says Dr. Gil L. Magsino, Head of the Training and Extension Division of the National Crop Protection Center, UP Los Banos, Philippines.
Every living organism needs water to survive, so keeping water clean from pollutants is something that concerns each and every one of us. However, it is an issue of special concern to agrochemical companies and to growers who strive to balance their need for effective weed control with safety for the environment. That’s were paraquat comes in. Comprehensive monitoring around the world confirms that paraquat does not contaminate ground water.
In their RED facts document, the US EPA concluded that “paraquat is not expected or considered to be a groundwater concern from normal paraquat dichloride use patterns” (US EPA, 1997).
Recent studies in France continue to confirm this assessment. The French monitoring of the ground and surface water is one of the best in the world and it has not detected any paraquat in its systems in almost a decade.
This held true in the most recent edition of “Les pesticides dans les eaux,” an annual national report on water contamination by pesticides.  In the report, which uses 2002 data, researchers identified the main molecules quantified in surface waters in 2002, across all networks (page 22, figure 10). The top five molecules listed were: atrazine, AMPA, atrazine déséthyl, glyphosate, and diuron.
Once again, paraquat was not detected.
The reason? Binding.
What is Paraquat?
Paraquat is a herbicide (chemical weed killer) used to control a very broad range of weeds (unwanted plants) in more than 100 crops, including cereals, oilseeds, fruit and vegetables, growing in all climates. Weeds shade crops, take their water and nutrients, and make harvesting difficult. The leading manufacturer of paraquat is Syngenta, which (as ICI) developed the active ingredient (AI) in the early 1960’s. Since then, paraquat has made possible many innovations in sustainable farming systems, based on its simplification of crop production by effectively controlling weeds and, in doing so, removing the need for ploughing to bury them. This has freed up farmers’ time and also helped care for the soil. Paraquat is one of the most widely used herbicides in the world. It has been approved for use by authorities in nearly 90 countries. When used as recommended, paraquat is effective and safe to users, consumers and the environment.
Key facts about the safe and effective use of paraquat are noted below. This fact sheet also contains a list of referenced scientific papers and other publications and a summary of technical information.
Why Farmers Use Paraquat
Spraying paraquat lets millions of farmers grow better crops more easily, while respecting the environment. Paraquat has a unique set of characteristics: