Paraquat, or paraquat dichloride, is a fast-acting, non-selective contact herbicide used primarily in large-scale agriculture. The chemical is extremely toxic and can cause severe illness or death if ingested, inhaled, or absorbed through the skin. Ingestion of even a small amount, such as a single teaspoon of the concentrated form, can be fatal, with no known antidote available.
Commercial Products and Common Brand Names
Paraquat dichloride is the active ingredient in numerous commercial herbicide products sold across the United States. The most recognizable and widely distributed brand name is Gramoxone, manufactured by Syngenta Crop Protection. Other widely known brand names that contain paraquat as the active ingredient include:
- Firestorm
- Parazone
- Quick-Quat
- Helmquat
Additional products registered for use may include Para-Shot, Cyclone, and Devour, offered by manufacturers such as Drexel Chemical Company and United Phosphorus.
Primary Agricultural Applications
The primary reason for the existence of paraquat-containing products is their effectiveness as a fast-acting burndown herbicide in commercial agriculture. Its non-selective nature means it kills all green plant tissue it contacts, making it highly effective for clearing fields rapidly before planting. This function is particularly important in no-till or reduced-tillage farming practices, where the herbicide is used to control weeds without disturbing the soil structure. Paraquat is heavily utilized for weed control in major row crops, including corn, cotton, and soybeans. Beyond pre-plant weed management, the chemical is also used as a desiccant or defoliant to prepare certain crops for harvest, such as cotton and potatoes.
Formulations and Concentration Levels
Paraquat is almost universally sold as a liquid concentrate. The concentration of the active ingredient, paraquat ion, typically falls around 20% or higher in the commercial products available in the U.S. To mitigate the risk of accidental ingestion, specific safety measures are mandatorily included in the product formulation. All liquid paraquat products sold in the U.S. must contain a blue safety dye, which serves to prevent the chemical from being mistaken for a beverage. The formulation also includes a sharp odor or a strong emetic, which is a vomiting agent, designed to cause the immediate rejection of the product if it is swallowed.
Regulatory Classification and Access Restrictions
Due to its acute toxicity and history of accidental poisoning, the U.S. Environmental Protection Agency (EPA) classifies paraquat as a Restricted Use Pesticide (RUP). This classification means that the products are not available for purchase or use by the general public, severely limiting access to reduce accidental exposure and misuse. Only certified applicators who have completed specialized training and possess a valid license are legally permitted to purchase, mix, or apply any product containing paraquat dichloride. Furthermore, the EPA mandates that all non-bulk containers (those under 120 gallons) must use closed-system packaging. This engineering control prevents the transfer of the product to secondary containers and minimizes the risk of accidental exposure during the mixing and loading process.