2,4-D Safety
Is 2,4-D safe?
Yes, 2,4-D products are safely used by following label directions. The EPA follows a rigorous process to confirm pesticide products are safe for human health and the environment.
All pesticides, including 2,4-D, have to pass a rigorous government approval process that can demand more than 150 safety studies and on average take nearly 12 years. Even after regulatory approval, the safety monitoring continues.
While every chemical, including water, poses risk at high enough concentrations, more than 90 regulatory bodies around the world charged with protecting human health and the environment, alongside thousands of scientists, have approved the safety of 2,4-D when used as directed.
You may have read claims alleging that 2,4-D can cause adverse health effects. Explore the facts on this page to learn more about its safety profile.
2,4-D has a recognized safety profile that goes back nearly a century
2,4-D is a modern herbicide with a recognized safety profile that goes back nearly a century and that continues to be repeatedly reviewed, re-examined, and retested to ensure it considers the latest scientific data and meets current standards for safe use. There are more than 4,000 peer-reviewed, published studies and articles on 2,4-D. Utilizing this scientific literature, regulatory authorities around the world have concluded that 2,4-D may be safely used as directed – meaning when it is used according to the label by farmers to control weeds. It should not be ingested or used for purposes other than intended.
2,4-D herbicides are repeatedly reviewed, re-examined and re-tested by regulatory bodies all over the world that are charged with protecting human health and environmental safety – more than 90 such bodies have approved the safety of 2,4-D when used as directed. As recently as 2020, the U.S. EPA reaffirmed its review of all available human health data on 2,4-D in a Human Health Assessment completed during the re-registration process for a major crop protection product and approved the safety of 2,4-D when used as intended. As part of that process, the U.S. EPA reviewed its previous findings as well as the most up-to-date human health safety data and information about 2,4-D, including dozens of new studies.
4,000
Number of studies conductead to-date on 2,4-D
2020
Year of the most recent re-registration made by the U.S. EPA for a 2,4-D herbicide product, approving the safety of 2,4-D when used as intended
90+
Number of international regulatory bodies that have determined 2,4-D is safe for humans when used as intended
2,4-D is approved by regulatory bodies all over the world
More than 90 regulatory bodies around the world have approved the safety of 2,4-D when used as directed, including:
- Health Canada
- Food Safety Authority (EFSA)
- Australian Pesticides and Veterinary Medicines Authority (APVMA)
- U.S. Environmental Protection Agency (EPA)
For each pesticide it reviews, the U.S. EPA evaluates hundreds of different scientific studies during the registration and re-registration process, relying on the best science available and placing high value on transparency in decision-making. During the process, the U.S. EPA may receive and review studies and information from manufacturers, third parties and the public, and takes findings and questions to independent expert panels such as the FIFRA Scientific Advisory Panel and the National Academy of Sciences. The EPA evaluates hundreds of scientific studies to evaluate the potential for product spray drift potential, surface water contamination and harm to humans — and ensures that product labels and directions for use are written specifically to avoid those kinds of harm.
So, by the time a product gets to market, it has undergone rigorous review – at times multiple decades’ worth of scientific studies – and scrutiny by multiple government agencies.
Learn More About The Pesticide Regulatory Journey.
What the studies say
2,4-D has been the subject of numerous long-term and laboratory-based studies in both high and low doses. Three separate U.S. EPA reviews of laboratory studies, conducted over nearly two decades, found that 2,4-D was not carcinogenic, classifying 2,4-D in their lowest category for concern as a potential cancer agent in humans:
“The epidemiology review found that, overall, there was little substantive evidence to suggest a clear associative or causal relationship between exposure to 2,4-D and cancer including non-Hodgkin lymphoma (NHL) in several cohort and case-control studies including the AHS (Agricultural Health Study.”
In addition, no other international regulatory body considers 2,4-D to be a human carcinogen.
Annals of Epidemiology, a peer-reviewed journal published by the American College of Epidemiology, published a meta-analysis that examined possible links between 2,4-D and non-Hodgkin’s lymphoma, gastric cancer and prostate cancer. The researchers found that 2,4-D was not associated with any of these diseases.
How does 2,4-D interact with the human body?
The U.S. EPA states that 2,4-D does not stay in the human body. 2,4-D is flushed out of the human body through urine and, if detected, it is at levels thousands of times below what the U.S. EPA deems safe for humans – levels that have remained unchanged in the U.S. population for decades. Here’s a look at what regulators are saying about the presence of 2,4-D in the human body:
- U.S. EPA >> “2,4-D undergoes limited metabolism in the body, and is eliminated quickly from the body primarily unchanged (73%-91%) in the urine.”
- Health Canada >> “It is normal to find the presence of a trace amount of a pesticide or other environmental contaminant in tissues or fluids when an individual has been exposed to it. However, exposure does not mean there will be a negative health effect, particularly if the levels are very small.”
To learn more, visit: www.epa.gov/ingredients-used-pesticide-products/24-d