10
Feb
Higher Disease Prevalence Among Farmers Highlights the Need Organic Practices and Compatible Materials
(Beyond Pesticides, February 10, 2022) A National Institute of Environmental Health Sciences (NIEHS)-funded study finds that patterns of pesticide exposure among farmers have geographical and temporal significance. Specific use of and exposure to organophosphate and carbamate chemicals decrease enzyme activity within the body, resulting in greater health anomalies among farmers, especially during agricultural seasons. The use of xenobiotic (foreign chemical compounds) substances like pesticides and fertilizers in agriculture are increasing. Thus, those working with and around these toxicants must have protection. Considering that agricultural workers often experience pesticide exposure at higher rates due to occupation, long-term research must identify potential health concerns surrounding common pesticides. The study author, Dana Barr, Ph.D., states, “The majority of farmers in this study reported that they had at least one health symptom associated with pesticide intoxication. This investigation can be used to promote safer use of pesticides among farmers and mitigate exposure among residents living near a rice field. The findings will be critical for establishing and launching several preventive programs in the future.”
Researchers evaluated the health effects of pesticide exposure among a cohort of farmers in Thailand during inactive and active rice farming periods. Using geographic information system (GIS) mapping, researchers compared acetyl- and butyryl-cholinesterase (AChE and BuChE) activities (a family of enzymes responsible for neurotransmission) among farmers across regions within the Ratchasima Province of Thailand. Scientists also collected data on the location of rice paddy fields. The results demonstrate that farmers exhibit higher adverse health symptoms from pesticide exposure during active farming periods. The main pesticides of concern are organophosphates and carbamates, due to the effects on enzyme function, as both AChE and BuChE activity decrease during active farming. Moreover, GIS mapping data shows enzyme inhibition within and adjacent to farms, indicating spatial and temporal changes in health.
The agricultural industry has a long-standing history of synthetic chemical use, which disproportionally affects farmworkers’ health. The journal Occupational and Environmental Medicine indicates that farmworkers and persons exposed to high levels of pesticides have an increased risk of developing brain tumors and over 45 different cancers. Farmworkers are at the highest risk of pesticide-induced diseases, and their average life expectancy bears this out. According to the National Farm Worker Ministry, farmworkers have an average life span of 49 years, a 29 year difference from the general U.S. population. Moreover, a recent study finds increased COPD for other pesticide-intensive occupations like landscapers (e.g., gardeners/landscapers). Although pesticide exposure through the skin or inhalation is most prevalent among individuals working around these toxic chemicals, pesticide exposure is ubiquitous and not only confined to a field. The general population can encounter toxic chemicals through residues in food and water or through chemical drift. Over 300 environmental contaminants and their byproducts—from chemicals in plastics to cosmetic/personal care products—are commonly found in water bodies, food commodities, and human blood/urine samples. These toxicants can alter hormone metabolism, producing endocrine-disrupting effects that put the health of animals, humans, and the environment at risk. Synthetic chemicals in pesticides can accumulate in bodies, causing an amalgamation of health effects. These effects can range from heightened risks of various cancers (i.e., prostate, hepatic, liver, etc.) and endocrine disruption to mental health problems (i.e., depression), respiratory illnesses (asthma), and many other pesticide-induced diseases. Therefore, understanding how pesticide exposure influences disease risk is essential in protecting the future of human, animal, and ecological health.
This study adds to the growing body of research demonstrating occupational exposure to pesticides contributes to higher disease prevalence among individuals working with and around these toxic compounds. Like this study, other researchers demonstrate that exposure to organophosphate insecticides, like chlorpyrifos, has endocrine disruption properties that induce neurotoxicity via acetylcholinesterase (AChE) inhibition in the nervous tissue. Inhibition of AChE can cause a buildup of acetylcholine (a chemical neurotransmitter responsible for brain and muscle function). This chemical buildup can lead to acute impacts, such as uncontrolled, rapid twitching muscles, paralyzed breathing, convulsions, and, in extreme cases, death. However, the inhibition of AChE is non-specific, making the dispersal of pesticides with this biological activity a severe threat to wildlife and public health.
Although hesitation to eliminate pesticides surrounds crop yields, studies as recent as 2022 show a ban on even the most extensively used pesticides have no adverse impacts on yield. Although this study takes place in Thailand, the results apply to conventional farmers across the globe. Adverse health effects related to pesticide exposure can occur regardless of geographical location and agricultural practices. For instance, cancer incidents are consistent among women and men agricultural workers, regardless of location, suggesting an underlying common risk factor (i.e., pesticides). Although farmers in the study use personal protective equipment (PPE), the equipment does not always protect against dermal exposure and inhalation after application (i.e., residues on clothing, shoes, hair, etc.). Moreover, current legislation fails to encompass the full impacts of pesticides on farmworkers, especially underrepresented individuals who disproportionately experience more severe health issues.
The study concludes, “[F]armers should be made aware of the safety practices of pesticide handling and application and the proper use of PPE through effective education and training programs. Importantly, the government should consider changing the current policy to allow effective restrictions of pesticide importation, production, and application. In addition, GIS can assist the assessment of agricultural pesticide exposure in the general population and can enable the location verification and pattern visualization of the OP and carbamate poisoning cases. Our work can be used to assist the establishment of a pesticide application free zone to minimize pesticide exposures in the residential areas.”
It is essential to know and understand the effects pesticides have on human health, especially if pesticides increase the risk of developing chronic diseases, particularly among vulnerable individuals. GIS-based pesticide exposure data can help public health officials make more targeted decisions regarding human health concerns. Moreover, GIS can incorporate numerous sources involving location, chemical, and time-period specific data. Beyond Pesticides tracks the most recent studies related to pesticide exposure through our Pesticide Induced Diseases Database (PIDD). This database supports the clear need for strategic action to shift from pesticide dependency. For more information on pesticide exposure harms, see PIDD pages on cancer, endocrine disruption, and other diseases.
One way to reduce human and environmental contamination from pesticides is to buy, grow, and support organic. Numerous studies find that pesticide metabolites in urine significantly drop when switching to an all-organic diet. Furthermore, given the wide availability of non-pesticidal alternative strategies, families and the agricultural sector can apply these methods to promote a safe and healthy environment, especially among chemically vulnerable individuals. For more information on how organic is the right choice for consumers, see Beyond Pesticides’ webpage, Health Benefits of Organic Agriculture. Furthermore, learn more about farmworker protection by visiting Beyond Pesticides’ Agricultural Justice page.
All unattributed positions and opinions in this piece are those of Beyond Pesticides.
