title: Drinking well water and occupational exposure to Herbicides is associated with chronic kidney disease, in Padavi-Sripura, Sri Lanka.
abstract: BACKGROUND
  The chronic kidney disease of unknown etiology (CKDu) among paddy farmers in was first reported in 1994 and has now become most important public health issue in dry zone of Sri Lanka. The objective was to identify risk factors associated with the epidemic in an area with high prevalence.
  
  
  METHODS
  A case control study was carried out in Padavi-Sripura hospital in Trincomalee district. CKDu patients were defined using health ministry criteria. All confirmed cases (N = 125) fulfilling the entry criteria were recruited to the study. Control selection (N = 180) was done from people visiting the hospital for CKDu screening. Socio-demographic and data related to usage of applying pesticides and fertilizers were studied. Drinking water was also analyzed using ICP-MS and ELISA to determine the levels of metals and glyphosate.
  
  
  RESULTS
  Majority of patients were farmers (N = 107, 85.6%) and were educated up to 'Ordinary Level' (N = 92, 73.6%). We specifically analyzed for the effect modification of, farming by sex, which showed a significantly higher risk for male farmers with OR 4.69 (95% CI 1.06-20.69) in comparison to their female counterparts. In the multivariable analysis the highest risk for CKDu was observed among participants who drank well water (OR 2.52, 95% CI 1.12-5.70) and had history of drinking water from an abandoned well (OR 5.43, 95% CI 2.88-10.26) and spray glyphosate (OR 5.12, 95% CI 2.33-11.26) as a pesticide. Water analysis showed significantly higher amount of hardness, electrical conductivity and glyphosate levels in abandoned wells. In addition Ca, Mg, Ba, Sr, Fe, Ti, V and Sr were high in abandoned wells. Surface water from reservoirs in the endemic area also showed contamination with glyphosate but at a much lower level. Glyphosate was not seen in water samples in the Colombo district.
  
  
  CONCLUSIONS
  The current study strongly favors the hypothesis that CKDu epidemic among farmers in dry zone of Sri Lanka is associated with, history of drinking water from a well that was abandoned. In addition, it is associated with spraying glyphosate and other pesticides in paddy fields. Farmers do not use personnel protective equipments and wears scanty clothing due to heat when spraying pesticides.
authors.affiliation: Department of Pharmacology, Faculty of Medicine, Rajarata University of Sri Lanka, Anuradhapura, 50008, Sri Lanka. jayasumanalk@yahoo.com.
authors.forename: Channa
authors.initials: C
authors.lastname: Jayasumana
authors.affiliation: Department of Chemistry, Faculty of Science, University of Kelaniya, Colombo, Sri Lanka.
authors.forename: Priyani
authors.initials: P
authors.lastname: Paranagama
authors.affiliation: Department of Community Medicine, Faculty of Medicine, Rajarata University of Sri Lanka, Anuradhapura, Sri Lanka.
authors.forename: Suneth
authors.initials: S
authors.lastname: Agampodi
authors.affiliation: Government Hospital, Padavi-Sripura, Sri Lanka.
authors.forename: Chinthaka
authors.initials: C
authors.lastname: Wijewardane
authors.affiliation: Department of Health Science, California State University Long Beach, Long Beach, CA, USA.
authors.forename: Sarath
authors.initials: S
authors.lastname: Gunatilake
authors.affiliation: Department of Medicine, Faculty of Medicine, Rajarata University of Sri Lanka, Anuradhapura, Sri Lanka.
authors.forename: Sisira
authors.initials: S
authors.lastname: Siribaddana
mesh_terms: D000328:Adult; D000368:Aged; D000382:Agricultural Workers' Diseases / Q000139:chemically induced* / Q000453:epidemiology; D000383:Agriculture; D016022:Case-Control Studies; D060766:Drinking Water / Q000009:adverse effects* / Q000032:analysis*; D004781:Environmental Exposure / Q000009:adverse effects; D005260:Female; D005308:Fertilizers / Q000032:analysis*; D006540:Herbicides / Q000009:adverse effects* / Q000032:analysis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000009:adverse effects; D015995:Prevalence; D051436:Renal Insufficiency, Chronic / Q000139:chemically induced* / Q000453:epidemiology; D012307:Risk Factors; D012959:Socioeconomic Factors; D013188:Sri Lanka / Q000453:epidemiology; D060986:Water Wells
chemical_list: D060766:Drinking Water; D005308:Fertilizers; D006540:Herbicides