Rohana Chandrajith1, Christian Zwiener2, Christoph Daniel3, Kerstin Amann3, Nishantha Nanayakkara4, Johannes A. C. Barth5
1 Department of Geology, Faculty of Science, University of Peradeniya, Peradeniya, Sri Lanka.
2 Environmental Analytical Chemistry, Department of Geosciences, Eberhard-Karls-University Tübingen, Schnarrenbergstr. 94-96, 72076 Tübingen, Germany.
3 Institute of Pathologe, Department of Nephropathology, Friedrich-Alexander-Universität (FAU), Erlangen Nürnberg Krankenhausstr. 8-10, 91054 Erlangen, Germany.
4 Nephrology and Kidney Transplant Unit, National Hospital, Kandy, Sri Lanka.
5 Department Geographie Und Geowissenschaften, GeoZentrum Nordbayern, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Schlossgarten 5, 91054 Erlangen, Germany.
Abstract
Chronic kidney disease of unknown aetiology (CKDu) occurs in tropical countries, including Latin America, Mexico, Sri Lanka, and India. The disease occurs mainly in men who work in the agricultural sector. Although many studies have been conducted in CKDu areas, hardly any have examined emerging organic contaminants (EOCs) in drinking water. Therefore, this study examined EOCs, including pesticide residues, pharmaceuticals, and personal care products, in 29 shallow groundwater samples collected from wells commonly used by CKDu patients. These patients were identified through renal biopsy examinations from the Girandurukotte and Wilgamuwa regions in the dry zone of Sri Lanka. Of 110 EOCs measured, 40 were found in at least one or more samples. Among the detected EOCs, all groundwater samples examined showed the highest concentrations of caffeine (max: 950 ng/L) and DEET (max: 647 ng/L). In particular, the insect repellents commonly used in the region, such as coils, mats, vaporizers, spray and creams, would be the source of DEET in the environment. Pharmaceuticals and personal care products were the most common EOCs in all groundwater samples, with concentrations ranging from 129 (propylparaben) to 1.26 ng/L (carbamazepine) and 1.25 ng/L (hydrochlorothiazide), respectively, followed by herbicides and fungicides. Sources of such compounds would be insect repellents, antifungal and bactericidal preservatives, and agricultural pesticides. Notably, none of the identified EOCs reached critical values and were often below the values in European drinking water standards. Although primary evidence of EOCs as a cause of the disease does not emerge from the results of this study, regular monitoring of EOCs in groundwater, particularly in the dry zone of Sri Lanka, is essential as the presence of these compounds highlights their vulnerability in shallow groundwater wells.
