15
Feb
One-Third of Americans Have Hazardous Weed Killer in Their Bodies
(Beyond Pesticides, February 15, 2022) A synthetic weed killer linked to cancer, endocrine (hormone) disruption, reproductive harm and birth defects can be found in the bodies of 1 in 3 Americans, according to research published in Environmental Health by scientists at George Washington University. The chemical in question is not glyphosate (though current data indicate similar results are likely) but 2,4-D, an herbicide that is increasingly used when weeds growing near genetically engineered (GE) crops have developed resistance to the repeated use of Roundup and other glyphosate-based weed killers. “Our study suggests human exposures to 2,4-D have gone up significantly and they are predicted to rise even more in the future,” Marlaina Freisthler, a PhD student and researcher at the George Washington University, said. “These findings raise concerns with regard to whether this heavily used weed-killer might cause health problems, especially for young children who are very sensitive to chemical exposures.”
Researchers conducted their analysis based on data from the National Health and Nutrition Examination Survey, which includes urinary concentrations of 2,4-D from 14,395 participants spanning 2001 to 2014. Between those years, the use of 2,4-D increased rapidly from its relative low point at the beginning of the century. “Roundup Ready” crops, introduced in the late 1990s, allowed farmers to broadcast spray both weeds and a genetically engineered, herbicide-tolerant crop with a Roundup (glyphosate) weed killer without killing the crop. Lacking any wisdom or forethought, the U.S. Environmental Protection Agency (EPA) deregulated the growing of these GE crops and permitted pesticide companies to create proprietary pesticides to go along with their engineered seeds. Vertical integration allowed an increasingly smaller number of agrichemical companies to dominate the market. According to data from the U.S. Department of Agriculture, over roughly 90% of corn, soy, and cotton produced in the United States is now GE. Unabated use of glyphosate-based herbicides has resulted in widespread damage, putting farmers, farmworkers, and the general public at increased risk of disease, and imperiling the environment.
Glyphosate’s success in its role as an all-in-one “silver bullet” weed killer has been predictably short-lived. Over the course of the 21st century, glyphosate has delivered diminishing returns in its ability to control GE crop weeds. As a result, chemical farmers are rapidly moving back to older chemistries like 2,4-D in order to stem the crisis of glyphosate-resistant weeds.
As 2,4-D increasingly supplemented glyphosate use, its use in the environment rose in lock-step with the body burden examined by scientists. In 2001, at the beginning of the study, 17.1% of those tested had 2,4-D present in their urine. By 2012, 39.6% of tested individuals had detectable urinary levels of 2,4-D. On average 32.5% of American residents tested had 2,4-D in their urine.
The results are particularly concerning for children, pregnant mothers, and agricultural workers. Those working with 2,4-D on farm had over 2x the chance of having high levels of 2,4-D contamination. Disturbingly, these high risks were similar to those seen for women and children. Women aged 20-44 were 2x more likely to be contaminated with 2,4-D than men of the same age. And children between the ages of 6-11 years were over 2x more likely to have high levels of 2,4-D than individuals aged 20-59.
“Further study must determine how rising exposure to 2,4-D affects human health–especially when exposure occurs early in life,” Melissa Perry, ScD, MHS, a professor of environmental and occupational health and senior author of the paper, said.
Current research describes a range of unacceptable hazards from 2,4-D exposure. The chemical is considered a possible human carcinogen by the International Agency for Research on Cancer, with concerns particularly pronounced for soft tissue sarcoma and non-Hodgkin lymphoma. 2,4-D is also associated with neurotoxicity, kidney/liver damage, and harm to the reproductive system. Research by EPA finds that babies born in counties where high rates of chlorophenoxy class herbicides like 2,4-D are applied to farm fields are significantly more likely to be born with birth defects of the respiratory and circulatory systems, as well as defects of the musculoskeletal system like clubfoot, fused digits, and extra digits. Studies have further implicated 2,4-D as playing a role in the development of ALS, loss of smell, and antibiotic resistance in human pathogenic bacteria.
As Dr. Perry notes, these concerns are exacerbated by the multitude of other chemical exposures that can occur in the environment. “In addition to exposure to this pesticide, children and other vulnerable groups are also increasingly exposed to other pesticides and these chemicals may act synergistically to produce health problems.”
Despite only beginning to understand how expanded uses of toxic pesticides like 2,4-D are harming the American public, applied amounts are only expected to grow. In 2014, EPA greenlit the approval of Enlist Duo, a successor to glyphosate’s toxic legacy on GE farm fields. Enlist Duo contains a combination of both glyphosate and 2,4-D, and was developed to be applied to crops genetically engineered to tolerate repeated spraying of Enlist Duo. Beyond Pesticides and other organizations sued EPA for approving the product without adequate consideration for its impact on endangered species, including monarch butterflies. Although EPA prevailed, US 9th Circuit Court Judge Paul Watford chastised the agency for its “scientifically unsound” approach that was criticized by the National Academies of Sciences as “not scientifically defensible.” In spite of these significant risks, EPA in mid-January 2022 renewed Enlist Duo for seven years, indicating that the changes made to the product’s label will somehow avert risks to endangered species, without any evidence of this happening under real-world conditions.
The cropping systems 2,4-D use supports are anachronistic and, if America is ever to make agriculture and land care sustainable, must be consigned to the dustbin of history. Organic agriculture, and its application to organic land care, has provided proof of concept that chemical pesticides are not necessary to grow healthy food or maintain beautiful landscapes. Although this approach may cost a bit more at the onset, it simultaneously eliminates the spillover harms caused by conventional chemical management. In other words, the minor cost increase with organic stops the development chronic health conditions caused by pesticide use, the creation of dead zones caused by synthetic fertilizers, and the broadscale poisoning of endangered species and their ecosystems caused by GE cropping systems. Instead of growing food with chemicals linked to declines in children’s IQ, eating organic is associated with higher scores for children on cognitive tests.
The supply problems of the pandemic are further exposing the house of cards that is U.S. chemical farming. Recent data show that since 2019, prices for conventional products have risen nearly 14%, while the cost of organic products a mere 1.6%. Those worried about their body burden of synthetic pesticide contamination are strongly encouraged to move to an organic diet. Most 2,4-D is eliminated from the body through urine within the first week of exposure – highlighting the frequency through which 1/3 Americans are being exposed to this chemical, per the Environmental Health study. Subsequent research shows that it takes roughly the same time eating an organic diet to significantly reduce the levels of synthetic pesticides in one’s body.
For more information on the danger 2,4-D and GE cropping systems, see Beyond Pesticides herbicide analysis, and webpage on herbicide tolerant crops. Learn more about why organic is the right choice for the future of farming and landscaping on our Why Organic and Non-Toxic Lawns and Landscapes webpages.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
Source: George Washington University press release, Environmental Health
