Glyphosate and fluoride in high-hardness drinking water are positively associated with chronic kidney disease of unknown etiology (CKDu) in Sri Lanka.

Chronic Kidney Disease of uncertain Etiology (CKDu) has emerged as a serious public health concern in farming communities globally, especially in Sri Lanka with 5-20% of the adult population affected by the disease in CKDu-endemic regions. It is hypothesized that drinking water contamination of glyphosate in combination with water hardness and co-occurring trace elements contribute to CKDu in Sri Lanka. However, no studies to-date have comprehensively examined this hypothesis. Here we conducted a large field study to measure and compare drinking water chemical burden in CKDu-endemic areas with CKDu-non-endemic areas in rural Sri Lanka. Chemical measures of water quality included glyphosate, water hardness, and trace elements including fluoride. Glyphosate was detected in 44% of endemic wells and 8% of non-endemic wells. Fluoride was detected in 99% of endemic wells and 80% of non-endemic wells. Logistic regression revealed that the presence of elevated glyphosate, fluoride, hardness, and vanadium in wells were positively associated with CKDu prevalence. The co-occurrence of glyphosate and high hardness indicate potential complexation of glyphosate in wells from CKDu-endemic areas. Collectively, our work represents the first definitive assessment of glyphosate presence in regions with geogenic high water hardness and fluoride and demonstrate a strong correlation with CKDu incidence.

Duke Scholars

Author Kate Hoffman Environmental Natural Science

Author P. Lee Ferguson Civil and Environmental Engineering

Author Nishad Jayasundara Environmental Natural Science