Map Shows States With Highest Use Of Harmful Pesticides

Newsweek

15 hours ago

Based on facts, either observed and verified firsthand by the reporter, or reported and verified from knowledgeable sources.
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Midwestern and Southern states use much higher rates of the potentially harmful pesticide 2,4-D, according to U.S. Geological Survey (USGS) data.
A map by USGS, based on the latest data, collected in 2019, shows that use is most prevalent across Iowa, Missouri, Kansas, Illinois, Indiana, Ohio, Kentucky, with other states also using the herbicide in certain areas.
2,4-D was found to be "possibly carcinogenic to humans" in a 2015 report by International Agency for Research on Cancer (IARC) in the World Health Organization (WHO), although the report states there was "inadequate evidence" at the time to determine the extent of its harm.
But there are justified concerns about potential harm, depending on exposure levels to 2,4-D.
Newsweek has contacted the Department of Agriculture (USDA) via email for comment.
Why It Matters
2,4-D has been used as a pesticide since the 1940s, and gained notoriety as one of the components of Agent Orange, the defoliant used by U.S. forces during the Vietnam War to destroy forestry and crops.
While the other component of Agent Orange, 2,4,5-T, contained high levels of dioxin which was found to cause cancer and other health problems, dioxins are reportedly not found at detectable levels in 2,4-D products sold and used in the United States, USDA said.
However, there is still some concern about the safety of its use, particularly as it has been used more widely in the last decade.
A map to show the use of 2,4-D pesticides in different US states.
A map to show the use of 2,4-D pesticides in different US states.
Uncredited/U.S. Geological Survey
What To Know
2,4-D is used to kill broadleaf weeds in various places, from lawns to fruit and vegetable crops, according to USDA.
"The Midwest, Great Plains, and Northwestern U.S. have the highest 2,4-D usage, largely because these regions are the primary producers of corn, soybeans, wheat, and other field crops that are commonly treated with 2,4-D," Gurumurthy Ramachandran, director of the Johns Hopkins Education and Research Center for Occupational Safety and Health, told Newsweek.
The increase in its use has been primarily due to the "rise of glyphosate-resistant weeds," Ramachandran said. Glyphosate, a once dominant herbicide, has become less effective as many weed species have developed resistance to it.
To combat these resistant weeds, farmers have turned to alternative herbicides like 2,4-D, given its effective and low-cost control of broadleaf weeds.
However, while USDA reported that "2,4-D generally has low toxicity for humans," others may disagree.
The herbicide has been linked to significant health concerns, including non-Hodgkin's lymphoma (NHL), endocrine disruption, a decrease in fertility and increase in birth defects, according to the nonprofit organization Natural Resources Defense Council (NRDC).
The IARC report detailed that there was "strong evidence that 2,4-D induces oxidative stress, a mechanism that can operate in humans, and moderate evidence that 2,4-D causes immunosuppression, based on in vivo and in vitro studies."
"However, epidemiological studies did not find strong or consistent increases in risk of NHL or other cancers in relation to 2,4-D exposure," it added.
The IARC also told Newsweek that the classification does not indicate the level of risk associated with a given level or circumstance of exposure.
"The cancer risk associated with substances or agents assigned the same classification may be very different, depending on factors such as the type and extent of exposure and the degree of the effect of the agent at a given level of exposure," the organization said.
The issue is that pesticides "can remain on or in food, and chronic dietary exposure has been linked to increased risks of metabolic syndrome, cancers, and other health problems," Ramachandran said.
They can also "contaminate water, air, and soil, potentially affecting people living near treated fields or those exposed through drift and runoff," he added.
This means that's its important for Americans to "wash all fruits and vegetables thoroughly before consumption; consider choosing organic produce to reduce dietary pesticide exposure, especially for children and pregnant women; and avoid entering fields or areas recently treated with pesticides and follow posted warnings," Ramachandran said.
What People Are Saying
Cynthia Curl, a professor in the School of Public and Population Health at Boise State University, Idaho, told Newsweek: "I think we need to be judicious in our use of these agricultural tools, understanding that exposures to these chemicals have been associated with adverse health effects. We should be supporting federal programs like the National Institute of Environmental Health Sciences, the United States Department of Agriculture, and the Occupational Safety and Health Administration that fund research, outreach and education to evaluate pesticide safety and support interventions to reduce pesticide exposures to workers, people living in agricultural communities and the general public."
David F. Goldsmith, an occupational and environmental epidemiologist at Milken Institute School of Public Health, George Washington University, Washington, D.C, told Newsweek: "I am concerned if farmers or farmworkers are not using effective safety gear and thus may be excessively exposed via inhalation or skin contact. I am also concerned that 2,4-D may contaminate drinking water sources. Although, I believe that there is a direct risk for people who buy produce from fields that have had 2,4-D used on them."
He added: "The public needs to be informed and vigilant about the use of herbicides, keeping them away from children, schools and using protective equipment such as gloves, face masks, and goggles. For farm workers, many of whom do not speak English, the information on the Material Safety Data Sheet needs to be translated and the farm managers who are sending them out into the fields need to ensure they have personal protective equipment, that they wear long sleeves and gloves."
Gerald LeBlanc, a professor in the Department of Biological Sciences, North Carolina State University, told Newsweek: "I am not concerned that 2,4-D may cause cancer in humans. IARC has classified 2,4-D as a Group 2B carcinogen, which means that it is possibly carcinogenic to humans. In my estimation, 2,4-D might cause cancer in humans, but only at unrealistically high exposure levels."
He added: "It's essential to recognize that toxicity is just one side of the coin when assessing chemical risk. The other side is exposure. Pesticide applicators are exposed to much higher levels than consumers of the agricultural products. Therefore, pesticide applicators may be at risk while the pesticide may pose no risk to consumers. The EPA sets limits on the amount of pesticides that can be found on agricultural products. As long as these limits are not exceeded, the pesticides are considered to be safe for human consumption. This is the case for 2,4-D, where residues associated with crops are typically well below levels that pose a risk of harm to consumers."
What's Next
Before the extent of the health impacts of 2,4-D are made clear, more research is needed and various governmental agencies are continuing to review the herbicide's safety.
It's also important to note, the USGS map is based on 2019 data, the latest data collected by the agency, so the prevalence and use of the pesticide may have changed in more recent years.
More recently, farmers have been finding "new replacements" for the pesticide, Diana S. Aga, a professor of chemistry at University at Buffalo, New York, and fellow of the American Chemical Society, told Newsweek.
The USGS also told Newsweek that final annual pesticide-use estimates, for approximately 400 compounds, from 2018 to 2022 will be published later this year.
"The pesticide use data releases are currently undergoing peer review, and we anticipate these products will be published around September 2025," they said.