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AIMS: The growing need to access recycled water as a source for drinking water supply necessitates management of perceived risks. This study aimed to use quantitative microbial risk analysis (QMRA) to evaluate microbiological risks of indirect water recycling. METHODS AND RESULTS: Scenario analyses of risk probabilities of pathogen infection were conducted to investigate four key quantitative microbial risk assessment model assumptions: treatment process failure, drinking water consumption events per day, inclusion or exclusion of an engineered storage buffer, and treatment process redundancy. Results demonstrated that the proposed water recycling scheme could meet WHO pathogen risk guidelines of ∼10-3 annual risk of infection under 18 simulated scenarios.

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Public drinking water system decisions about treatment processes are becoming more challenging, especially as regulations become more stringent and source water quality degrades. For small systems that serve <10,000 people, treatment decisions are particularly difficult due to limited resources and because they do not currently have resources to help them make informed and sustainable decisions using environmental, social, and economic criteria. Therefore, a user-friendly sustainability assessment framework, which compares treatment processes relevant to a wide variety of small drinking water systems, was constructed. In summary, the framework uses life cycle assessment and multiple-criteria decision analysis to comprehensively evaluate twelve decision criteria, developed specific to small drinking water systems; the framework then uses an aggregation approach to identify and navigate multiple trade-offs and make a final recommendation based on stakeholder values. Four hypothetical scenarios were examined to show the framework's applicability to diverse small systems, ability to help stakeholders navigate trade-offs, and engineering relevance. The framework is universal in its capacity to evaluate systems with different design parameters, source waters, treatment criteria, and stakeholder preferences.

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Small drinking water systems serve a fifth of the U.S. population and rely heavily on disinfection. While chlorine disinfection is common, there is interest in minimizing chemical addition, especially due to carcinogenic disinfection byproducts and chlorine-resistant pathogens, by using ultraviolet technologies; however, the relative, broader environmental impacts of these technologies are not well established, especially in the context of small (<10 000 people) water systems. The objective of this study was to identify environmental trade-offs between chlorine and ultraviolet disinfection via comparative life cycle assessment. The functional unit was the production of 1 m3 of drinking water to U.S. STANDARDS: Treatment included cartridge filtration followed by either chlorine disinfection or ultraviolet disinfection with chlorine residual addition. Environmental performance was evaluated for various chlorine contact zone materials (plastic, concrete, steel), ultraviolet validation factors (1.2 to 4.4), and electricity sources (renewable; U.S. average, high, and low impact grids). Performance was also evaluated when filtration and chlorine residual were not required. From a life cycle assessment perspective, replacing chlorine with UV was preferred only in a limited number of cases (i.e., high pumping pressure but filtration is not required). In all others, chlorine was environmentally preferred, although some contact zone materials and energy sources had an impact on the comparison. Utilities can use these data to inform their disinfection technology selection and operation to minimize environmental and human health impacts.

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BACKGROUND: Coronary artery disease (CAD) is the leading cause of death and a leading cause of disability in the developed world. Early onset (premature) coronary artery disease (EOCAD) is known to have a particularly strong genetic component. However, the actual genes leading to this increased risk of CAD remain obscure. METHODS: The primary goal of the Genetics of Early Onset Cardiovascular Disease (GENECARD) study is to perform a genetic linkage study in 920 families with at least 1 sibling pair having EOCAD. The study sites include a US network of 15 cardiology practices and 5 additional sites located in Europe and the United States. We propose to identify chromosomal regions associated with increased susceptibility to EOCAD in this large sample of affected sibling pairs and nuclear families, where EOCAD is defined on the basis of having acute coronary syndrome (unstable angina or myocardial infarction), a revascularization procedure, or a positive functional imaging study at or before the age of 50 years in men or 55 years in women. To identify which genomic regions and genes are associated with increased susceptibility to EOCAD, we will use a comprehensive strategy comprising genomic screening, fine mapping, candidate gene analysis, and family-based association studies. RESULTS: Herein we describe the clinical characteristics, family history, and risk factor profiles of the 1168 members from 438 nuclear families included in the first, exploratory analysis. Analysis of the study population revealed a strong concordance of known cardiac risk factors among affected sibling pairs. There was significant concordance (P <. 01) among siblings with EOCAD for presence of diabetes (78% concordance), dyslipoproteinemia (67%), obesity (63%), and hypertension (56%). This level of concordance of risk factors among siblings might be expected, given the significant genetic components demonstrated for these metabolic susceptibility traits. However, there was also substantial sibling pair concordance (P <.01) for smoking history (74%), regular alcohol consumption (81%), and sedentary lifestyle (63%), environmental traits without known inherited predisposition. CONCLUSIONS: Analyses such as these will have implications for stratifying populations for the statistical analysis of the genome scan and on the choice of covariates for the follow-up studies of the initial genome screen analysis.

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