Paraquat Dichloride
In October 2020, EPA took an important step in its regulatory review of paraquat—an herbicide used in agricultural and commercial settings only. The Agency is seeking public input on the Proposed Interim Decision. The Proposed Interim Decision proposes new mitigation measures to reduce potential ecological risks and protect public health based on the findings in the draft risk assessments and comments submitted during the public comment period. The Proposed Interim Decision is the next step in the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA) registration review process and is not a denial or an approval of the herbicide.
- The proposed interim decision for paraquat is now available for public comment for 60 days in docket EPA-HQ-OPP-2011-0855 at www.regulations.gov, closing on December 22, 2020.
After public comments on the Proposed Interim Decision are reviewed, the Agency will issue an Interim Decision announcing any required mitigation measures.
Basic Information on Uses
Paraquat dichloride, commonly referred to as “paraquat,” is one of the most widely used herbicides in the United States. Paraquat is also often referred to as Gramoxone (a popular end-use product). It is an important tool for the control of weeds in many agricultural and non-agricultural settings. It is also used for desiccation of crops, like cotton, prior to harvest.
There are no homeowner uses and no products registered for application in residential areas.
All paraquat products registered for use in the United States are Restricted Use Pesticides (RUPs) that may only be used by trained certified applicators.
Using Paraquat Dichloride Products Safely
If you, your child or anyone else comes in contact with paraquat, seek medical assistance immediately. Ingestion of paraquat can be fatal, and dermal or eye contact can have serious lasting effects.
To prevent severe injury and/or death from paraquat ingestion, all paraquat products must:
- Be used only by a certified applicator. Unlike most other restricted-use products, paraquat may not be used by persons working under the supervision of a certified applicator.
- Never be transferred to a food, drink or any other container. New packaging requirements will help to prevent this from occurring.
- Always be kept secured to prevent access by children and/or other unauthorized persons.
- Never be stored in or around residential dwellings.
- Never be used around home gardens, schools, recreational parks, golf courses or playgrounds.
To prevent severe injury and/or death from skin or eye exposure to paraquat:
- Follow label instructions.
- Use the required personal protective equipment specified on the product label.
Human Health
Paraquat is highly toxic. One small sip can be fatal and there is no antidote.
Illegally transferring paraquat to beverage containers and later mistaking it for a drink has resulted in the accidental ingestion of the pesticide and causes approximately 1-2 deaths per year. New packaging requirements and other risk mitigation measures required by EPA in 2016 are expected to minimize the illegal transfer of paraquat to beverage containers. Incidents also suggest that paraquat is corrosive to the skin and eyes.
In the 2019 draft human health risk assessment, EPA found no dietary risks of concern associated with paraquat when it is used according to the label instructions. The draft risk assessment identifies potential risks to workers who apply paraquat or enter treated fields after application. There are also potential risks from spray drift to bystanders at the edge of the field. EPA’s Proposed Interim Decision, which is available for public comment until December 22, 2020, proposes several mitigation measures to address these potential risks.
EPA reviewed a robust set of literature on paraquat exposure which included over 70 articles that investigated a range of health outcomes, including Parkinson’s Disease, lung function and respiratory effects, and cancer. Based on this review, EPA concluded that there is insufficient evidence to link registered paraquat products to any of the health outcomes investigated, including Parkinson’s Disease, when used according to the label.
Ecological Health
The 2019 draft ecological risk assessment identifies potential risk to mammals, birds, terrestrial invertebrates, terrestrial plants, and algae.
Proposed mitigation outlined in EPA’s Proposed Interim Decision, which is available for public comment until December 22, 2020, is expected to reduce these risk concerns.
EPA Actions
Actions to Prevent Accidental Ingestion and Reduce Exposure to Workers
In 2016, to minimize accidental paraquat ingestions and to reduce exposure to workers who mix, load and apply paraquat, EPA is requiring:
- Changes to the pesticide label and distribution of supplemental warning materials to highlight the toxicity and risks associated with paraquat products.
- Restricting the use of paraquat to certified pesticide applicators only. Individuals working under the supervision of a certified applicator are prohibited from using paraquat.
- Specialized training for certified applicatorsExit who use paraquat to emphasize that the chemical should not be transferred to or stored in improper containers.
- New closed-system packaging designed to prevent transfer or removal of the pesticide except directly into proper application equipment. This will prevent spills, mixing or pouring the pesticide into other containers or other actions that could lead to paraquat exposure.
These mitigation measures are described in detail, along with implementation information in the Registration Review Docket. View the 2016 Paraquat Dichloride Human Health Decision mitigation measures.
EPA distributed a safety message that highlights the toxicity of paraquat and illustrates the negative repercussions of misusing paraquat to pesticide application educators for use in training sessions. View EPA’s paraquat safety message.
Registration Review
Paraquat is currently undergoing registration review, a program that re-evaluates all pesticides on a 15-year cycle. In October 2019, EPA released the draft human health and ecological risk assessments for public comment.
EPA has completed review of the public comments, and in October 2020 released the Proposed Interim Decision. In this document, EPA is proposing the following protections to reduce exposure to paraquat.
- Prohibiting aerial application for all uses and use sites except cotton desiccation; Prohibiting pressurized handgun and backpack sprayer application methods on the label;
- Limiting the maximum application rate for alfalfa to one pound of active ingredient per acre;
- Requiring enclosed cabs or PF10 respirators if area treated in 24-hour period is 80 acres or less;
- Requiring a residential area drift buffer and 7-day restricted entry interval (REI) for cotton desiccation;
- Requiring a 48-hour REI for all crops and uses except cotton desiccation; and
- Adding mandatory spray drift management label language.
In addition, EPA is proposing to allow truck drivers who are not certified applicators to transport paraquat when certain conditions are met.
After considering public comments the Agency will issue an Interim Decision with any required mitigation measures.
Paraquat Dichloride Information Resources
- Syngenta’s Paraquat Information Center Exit
- Docket for paraquat: EPA-HQ-OPP-2011-0855 at www.regulations.gov.