A major national survey has revealed that one in three Americans has detectable levels of a toxic herbicide related to cancers, birth defects, and hormonal imbalances.
According to the first national representative study, human exposure to 2,4-D has increased significantly amid growing use by farmers, despite numerous health and environmental concerns.
The herbicide was created in the mid-1940s. It quickly became the preferred weedkiller for farmers who wanted to increase crop yields. However, it also gained popularity with gardeners who want a beautiful lawn.
Its popularity declined in favor of Roundup (glyphosate), genetically modified cotton, and soyabeans that are resistant to this herbicide. However, it has seen a resurgence after the spread of Roundup resistance weeds.
2,4-D is currently on the rise due to the Whac–a-Mole method of pest control in industrialised farms. There are about 600 US residential and agricultural products that contain the chemical. It can be ingested through your skin, mouth, or nose.
Researchers at George Washington University examined urine samples from 14,395 participants in the annual National Health and Nutrition Examination Survey. They searched for biomarkers of the pesticide and compared exposure levels with 2,4-D between 2001 and 2014.
The popularity of the pesticide grew among gardeners as well as farmers. Human exposure to it increased from 17% in 2001/02 to almost 40% a decade later.
High levels of 2,4 D, an ingredient in Agent Orange that was used against civilians in Vietnam, have been linked to cancers, including leukemia, birth defects, and reproductive problems, among other health issues.
Although there is not much information about the effects of low-level herbicide exposure, it does disrupt hormone production in the endocrine systems, which are the glands that produce hormones that regulate growth, development, metabolism, mood, and other functions.
The study was published online in Environmental HealthResearchers found that exposure to 2,4-D was not uniform. Subgroups such as children aged 6-11 years and women in childbearing years had significantly higher levels of the compound in their urine. The most harmful time to be exposed to toxic substances is during key developmental periods, such as pregnancy or early childhood.
Melissa Perry, senior author and professor of occupational health and environmental health, said that further research is required to determine the effects of rising exposures of 2,4-D on human health. This is especially true when exposure occurs in early life. Children and other vulnerable people are also being exposed to pesticides, and these chemicals could work together to cause health problems.
The study also showed that Black participants were more likely to be exposed to weedkiller than white Americans, despite previous studies showing this to be the case. Researchers believe this could be due to historical racist policies that restricted access to gardens and green spaces for Black communities.
Overall, 2,4-D was applied to agriculture 67% more between 2012 and 2020. But its use will almost certainly increase sharply over ten years because of the widespread use Enlist Duo, a controversial combination (2,4 D and glysophates), for genetically modified crops. This will make it harder to avoid both toxins that are currently banned in certain countries.
Our study shows that human exposures to 2,4D have increased significantly, and they are expected to continue rising in the future, says Marlaina Freisthler (a PhD student and coauthor of the study). We don’t believe increasing exposures or use is the right direction given the potential human and environmental health consequences of such widespread exposures.