For two decades, tens of thousands of people living in rural Sri Lanka have faced an epidemic known as CKDu, a form of kidney failure with unclear causes. Similar patterns of kidney disease have emerged in farming regions around the world, prompting researchers to investigate potential links to environmental factors in tropical agricultural settings.
Fieldwork examining wells that supply drinking water in Sri Lankan communities was conducted by researchers from Duke University. A suspected contributor is glyphosate, the active ingredient in Roundup. Glyphosate is the most widely used herbicide globally, including in Spain.
The results appeared in Environmental Science & Technology Letters last September.
Roundup is a glyphosate-based herbicide used to control weeds and other pests. It is often perceived as having a short environmental persistence, leading to relatively light regulation by public health authorities in many places.
Analyses were performed across numerous drinking water wells. The investigation highlighted the complex behavior of glyphosate when it meets certain metal ions, such as magnesium and calcium, which can form stable compounds with glyphosate. These complexes may persist in water for up to seven years and in soil for as long as twenty-two years, according to researchers.
This challenges the common assumption that glyphosate breaks down quickly in the environment. The study notes that glyphosate can linger longer than previously thought and urges examination of how the chemical interacts with other elements and how it behaves if it enters the body as part of a complex, said Nishad Jayasundara, a professor at Duke University focused on global environmental health.
CKDu Impact on Children in Affected Regions
In certain agricultural districts of Sri Lanka, hot, dry climates and regional geology create conditions favorable to hard water. CKDu kidney failure has reached epidemic levels in these areas, with up to ten percent of children aged five to eleven showing early signs of kidney damage.
Further analysis noted elevated glyphosate levels in a significant portion of wells within the affected regions compared with areas outside these zones. The research team used high-resolution mass spectrometry to identify contaminants, including traces of the herbicide, offering precise measurement of water quality. This technique enabled researchers to quantify contaminants by molecular weight with remarkable sensitivity.
Exposure Pathways and Additional Contaminants
The study suggests that exposure may occur through several routes, including direct contact for agricultural workers and possibly through contaminated food or dust. The researchers emphasized the need for more studies to map these exposure pathways comprehensively and to understand how they contribute to CKDu risk in communities relying on local groundwater.
High fluoride and vanadium levels were also detected in the drinking water of many communities with high CKDu incidence. The team agrees that attention should be paid to the combined impact of these pollutants along with glyphosate, whether acting alone or in concert with other contaminants.
Scientists view these findings as a warning about the potential health risks of glyphosate exposure. A notable concern is the similarity between the properties of glyphosate and those of perfluorinated substances, commonly referred to as PFAS. PFAS are known for their persistence, mobility, and potential health effects as drinking water contaminants. The research team suggests that glyphosate may share these persistent characteristics, especially in hard water zones.
Reference work: DOI: 10.1021/acs.estlett.3c00504
Researchers note that further field and laboratory work is needed to fully understand exposure pathways and long-term health implications. The study presents a clear warning about the risks associated with glyphosate in groundwater and highlights the importance of evaluating water quality in regions affected by CKDu.
The environmental science community continues to monitor these findings and advocate for more robust water testing, stricter regulation where warranted, and ongoing research into the interactions between glyphosate, hard water minerals, and other contaminants in rural water supplies.
For those seeking more information, ongoing studies remain focused on measuring contaminant levels in wells and laboratories, with the goal of identifying practical steps to protect vulnerable communities while supporting sustainable agricultural practices.