Hard water contaminated by glyphosate herbicides may explain high levels of kidney disease in rural Sri Lanka.
The active ingredient in Roundup, the world’s most popular herbicide, may play a role in the epidemic levels of chronic kidney disease seen in rural Sri Lanka, a new study suggests.
Published in Environmental Science and Technology Letters, the large field study sampled water sources located in areas with and without high numbers of kidney disease cases. The research team found that the chemical glyphosate, as well as fluoride, vanadium and water hardness within the water wells, were all associated with high local levels of chronic kidney disease.
The mysterious roots of kidney disease clusters
For the past two decades, rural communities in Sri Lanka have been struggling with abnormally high rates of an unusual form of kidney disease. Cases of chronic kidney disease of unknown etiology (CKDu), as it is known, are not linked to any of the commonly known risk factors for kidney disease, including diabetes mellitus, hypertension or glomerular nephritis.
Since these CKDu cases were first spotted among rice paddy farmers in Sri Lanka’s North Central Province, cases have continued to spread. One recent study suggests that around 9% of children (aged 5–11 years) in the North Central Province are now exhibiting signs of early onset kidney damage. Similar incidences of the mysterious CKDu disease have also emerged among tropical farming communities worldwide.
To improve understanding of these epidemic levels of CKDu, researchers are investigating numerous other environmental factors in search of anything that might be causing kidney problems.
One possible culprit is glyphosate, the active compound used in many popular herbicides. While this compound is normally broken down relatively quickly in the environment, it can form complexes with the metal ions present in hard water – such as magnesium and calcium – which can affect its physical properties. Some research suggests that these glyphosate–metal ion complexes can survive for up to 7 years in water and 22 years in soil environments.
“It was always thought that this chemical would break down very quickly in the environment, but it seems to stick around a lot longer than we expected when it complexes in hard water,” said study author Nishad Jayasundara, the Juli Plant Grainger Assistant Professor of Global Environmental Health at Duke. “We have to consider how glyphosate is interacting with these other elements, and what happens to glyphosate when you take that into your body as a complex.”
While Sri Lanka banned the use of glyphosate-based herbicides for several years, Jayasundara, , who is from Sri Lanka himself, believes that this compound could still be harming the country’s rural communities.
Glyphosate discovered in local wells
For this study, Jayasundara teamed up with research groups led by environmental analytical chemist Lee Ferguson, an associate professor of civil and environmental engineering at Duke, and Mangala De Silva, a professor in the Department of Zoology at the University of Ruhuna, Sri Lanka.
Together, the research team collected water samples from more than 200 wells across 4 geographic regions in Sri Lanka. This included 154 wells located in areas with endemic levels of CKDu cases.
Using liquid chromatography with tandem mass spectrometry (LC-MS/MS), the researchers analyzed each sample for the presence of any glyphosate. Fluoride levels were examined using an in-field ion selective electrode (ISE) meter, while a portable spectrophotometer was used to evaluate water hardness and the presence of calcium and magnesium ions. Additional trace metal analysis was also carried out by inductively coupled plasma-mass spectrometry (ICP-MS).
*Original full-text article online at: https://www.technologynetworks.com/applied-sciences/news/popular-herbicide-ingredient-linked-to-chronic-kidney-disease-epidemic-in-sri-lanka-379827
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