The recent emergence of an apparently new form of chronic kidney disease of unknown aetiology (CKDu) has become a serious public health crisis in Sri Lanka. CKDu is slowly progressive, irreversible, and asymptomatic until late stages, and is not attributable to hypertension, diabetes, or other known aetiologies. In response to the scope and severity of the emerging CKDu health crisis, the Sri Lanka Ministry of Health and the World Health Organization initiated a collaborative research project from 2009 through 2012 to investigate CKDu prevalence and aetiology. The objective of this paper is to discuss the recently published findings of this investigation and present additional considerations and recommendations that may enhance subsequent investigations designed to identify and understand CKDu risk factors in Sri Lanka or other countries.

The incidence of chronic kidney disease of unknown or uncertain etiology (CKDu) is recognized as a global non-communicable health crisis. The goal of this work is to compare the types of research studies in Latin America and Asia, two regions with increasing CKDu incidence. A comparative literature review was conducted to evaluate the CKDu research design for peer-reviewed articles published from 2015 to 2019. Full texts were reviewed to identify study location, study type, study design, risk factors evaluated, and if applicable, sample type and number. In Asia and Latin America, 82 and 65 articles were identified in total, respectively, with 55 field studies in Asia versus 34 in Latin America. In Asia, research was focused on drinking water (34), heavy metals (20), and agrochemical product usage (19) as potential risk factors. In Latin America, research focused mostly on heat stress/dehydration (36) and agrochemical product usage (18) as potential CKDu risk factors. Biological samples were collected more frequently than environmental samples, especially in Latin America. Research to pinpoint the risk factors associated with CKDu to date is not standardized and typically limited in geographical scope. The emphasis of CKDu research varies by geographic region, with a greater priority placed on water quality and chemical exposure in Asia, versus dehydration and heat stress in Latin America. Using a harmonized approach to CKDu research would yield improved understanding of the risk factors associated with CKDu and how they compare across affected regions.

Drinking water is a lingering hazard in the effort to eliminate childhood exposure to lead (Pb), a neurotoxin that affects cognitive and behavioral development. This study characterized Pb in municipal drinking water at North Carolina, US, childcare centers. The study also demonstrates a scalable, citizen science-based drinking water testing strategy for Pb at childcare centers. Licensed childcare centers in four North Carolina counties were recruited. One administrator per center completed a survey and was trained to collect first-draw drinking water samples in their center. Samples were shipped with pre-paid labels for laboratory analysis using inductively coupled plasma mass spectrometry. Multilevel logistic regression and Bayesian network analysis were used to identify factors associated with a risk of exceeding the 1 μg/L American Academy of Pediatrics reference level and the US Environmental Protection Agency (US EPA) 15 μg/L treatment-based action level. Results were provided to centers along with risk mitigation recommendations. Of 103 enrolled centers, 86 completed the study, submitting 1,266 drinking water samples in total. Approximately 77% of drinking water samples contained detectable Pb (≥0.1 μg/L), and 97% of centers had at least one drinking water sample with detectable Pb. More than 63% of centers had at least one drinking water sample with >1 μg/L Pb, and 17% of centers had at least one drinking water sample with Pb above 15 μg/L. There was high variability in Pb concentrations at water points within the same center. This study demonstrated a high prevalence and variability of Pb in first-draw samples of drinking water at childcare centers in North Carolina, US. Results underscore the importance of testing for Pb at every tap used for drinking and cooking in childcare centers. The use of employees as citizen scientists is a feasible strategy to identify Pb in specific drinking water taps.

Beer has been a popular beverage for millennia. As water is a main component of beer and the brewing process, we surmised that the polyfluoroalkyl substances (PFAS) presence and spatial variability in drinking water systems are a PFAS source in beers. This is the first study to adapt EPA Method 533 to measure PFAS in beer from various regions, brewery types, and water sources. Statistical analyses were conducted to correlate PFAS in state-reported drinking water, and beers were analyzed by brewing location. PFAS were detected in most beers, particularly from smaller scale breweries located near drinking water sources with known PFAS. Perfluorosulfonic acids, particularly PFOS, were frequently detected, with PFOA or PFOS above U.S. EPA's Maximum Contaminant Limits in some beers. There was also a county-level correlation between the total PFAS, PFOA, and PFBS concentrations in drinking water and beers. Given that approximately 18% of U.S. breweries are located within zip codes with detectable PFAS in municipal drinking water, our findings, which link PFAS in beer to the brewery water source, are intended to help inform data-driven policies on PFAS in beverages for governmental agencies, provide insights for brewers and water utilities on treatment needs, and support informed decision-making for consumers.