The Groundwater Geochemistry and the Human Health Risk Assessment of Drinking Water in an Area with a High Prevalence of Chronic Kidney Disease of Unknown Etiology (CKDu), Sri Lanka

Abstract

Chronic kidney disease of unknown etiology (CKDu) has become an alarming health issue in Sri Lanka. The disease is more notable among farming communities and people who consume groundwater as their main source of drinking water. To assess the possible links between drinking water chemistry and expansion of CKDu, the study was compared with hydrogeochemical data of drinking water sources in a CKDu prevalent area (Girandurukotte GND, Badulla District) and a reference area (Dambethalawa GND, Ampara District) in Sri Lanka. Based on the results, nephrotoxic heavy metal (Cd, Cr, Pb, and As) concentrations were significantly higher in the CKDu prevalent site than the reference area, compromised the harmful consequences to the people in the CKDu hotspot. Results of the inverse distance weighted (IDW) interpolation tool indicated the nephrotoxic heavy metals contents including Cd, Pb, As, and Cr in CKDu hotspot were changed in the ranges of 9.78–187.25 μg/L, 0.08–0.66 μg/L, 20.76–103.30 μg/L, and 0.03–0.34 μg/L. The random distribution patterns were shown by the result in Moran’s index values. Noteworthy, the results have emphasized a strong association between fluoride and water hardness. The frequency of occurrence above the threshold limit of fluoride was 28% in non-CKDu water samples, while 81% in CKDu prevalent sites. The hardness values in the CKDu prevalent site indicated “moderately hard water,” while the non-CKDu area indicated the “soft water.” Furthermore, this paper quantified overall water quality and heavy metal contamination and assessed the human health risks associated with drinking water. According to the results of the water quality index, 90% of the samples in the CKDu prevalent area were classified as “poor water” and “very poor water” for drinking purposes, while 73.33% of the samples in the non-CKDu area were “good” and “excellent” for drinking usage. Calculated chronic daily intake (CDIoral) and hazard quotient (HQoral) of nephrotoxicants were higher in CKDu hotspot than the non-CKDu site. Besides, the hazard index (HI) values obtained for the CKDu prevalent area exceeding the acceptable limit (HI = 1) indicated potential health risks to the people in those areas. This study suggests that long-term exposure to nephrotoxic heavy metals, water hardness, and fluoride present in drinking water may threaten human health and affect kidney functions. Therefore, regular monitoring and better management of water supplies in CKDu prevalent areas are essential to determine the contamination load and reduce the health impacts due to excessive and long-term exposure to the nephrotoxicants.

THE CHRONIC KIDNEY DISEASE OF UNKNOWN AETIOLOGY (CKDu) EPIDEMICS IN NORTHERN YOBE STATE

“…The wisdom behind this is that it will allow spatial assessment of the disease aetiology in the area since the majority of the previous studies implicated environmental compounds and factors for the disease epidemics. It has been reported that the distribution of environmental nephrotoxic compounds such as cadmium and Arsenic can be influenced by various confounding factors, including local geology, as well as anthropogenic activities (Botheju et al, 2021). Thus, cross-mapping the disease incidence location to identify hotspots as well as surrounding area environmental factors assessment is critically crucial.…”

“…Essentially, this issue of heavy metals exposure needs to be carefully examined since the local population sourced and used water from shallow boreholes and wells that are suspected to be contaminated with agrochemicals in the area. It has been highlighted in the literature that one or more of these trace elements and their synergies induces renal damage as reported byWasana et al (2017) andBotheju et al (2021).…”

Electrospun amine-functionalized silica nanoparticles–cellulose acetate nanofiber membranes for effective removal of hardness and heavy metals (As(v), Cd(ii),Pb(ii)) in drinking water sources

“…The heavy metal concentrations in the mixture were decided based on the highest reported contamination of drinking water sources in CKDu prevalent areas. 35,36 The membrane was then dipped in 30 ml of food grade vinegar solution for 1 hour and washed with deionized water several times. The recycled membrane was then used in the subsequent adsorption of cation mixtures.…”

Prevalence and risk factors for chronic kidney disease in Indonesia: An analysis of the National Basic Health Survey 2018

“…First is as a result of the ineffective control of infectious, re-emerging, and newly emerging diseases; second is due to the rise of chronic diseases into the top five list of catastrophic disorders as a result of demographic and nutritional transitions; and lastly because of the steady increase in the incidence of trauma and injuries [ 7 ]. In addition, the influence of environmental factors also needs to be considered in the progression of CKD, especially the clean water source which could contribute to the waterborne diseases and diarrheal illnesses leading to acute kidney injury (AKI), schistosomiasis that can cause CKD, and water pollution that further causing CKD [ 8 , 9 ].…”