Health impact assessment of coal-fired boiler retirement at the Martin Drake and Comanche power plants

Includes bibliographical references.Health impact assessment (HIA) is a suite of tools used to characterize potential health effects of policies, projects, or regulations. The objective of this HIA was to understand the impact of decommissioning units at two large coal-fired power plants on mortality and morbidity in the Southern Front Range region of Colorado. Based on Community Multiscale Air Quality (CMAQ) chemical transport models of fine particulate matter with an aerodynamic diameter less than 2.5 μm (PM2.5) and ozone (O3), we modeled five potential emissions reductions scenarios and estimated the potential health benefits of reduced exposures to PM2.5 and ozone for premature deaths, cardiovascular and respiratory hospitalizations, and other health outcomes for ZIP codes in the Southern Front Range region, including the cities of Denver, Colorado Springs, and Pueblo. Health Benefits Scenarios 1 and 2 estimated the health benefits of shutting down most units at the Comanche plant in Pueblo, CO (one newer unit remained operational) relative to a baseline scenario using emissions from 2011 (Scenario 1) or a counterfactual baseline scenario that accounted for sulfur dioxide emissions controls (scrubbers) installed at the Martin Drake plant in Colorado Springs in 2016 (Scenario 2). Health Benefits Scenario 3 estimated the benefits of shutting down the Martin Drake plant relative to the 2011 baseline. Health Benefits Scenario 4 estimated the health benefits of shutting down the Martin Drake power plant and shutting down all but one boiler at the Comanche power plant relative to a 2011 emissions baseline. Health Benefits Scenario 5 estimated the marginal health benefits of decommissioning these plants (with one remaining coal-fired boiler at Comanche) relative to a counterfactual baseline year that considered emissions controls installed at the Martin Drake facility in 2016. In addition to estimating the number of deaths, hospitalizations, and other health outcomes that would potentially be avoided by reducing emissions at these facilities, we also estimated the monetary impact using outcome valuations typically used in US EPA health benefits analyses and examined the environmental justice implications of reduced emissions and exposures across the Southern Front Range. • For Health Benefits Scenario 1 (Comanche Units 3 and 4 were “zeroed out” and compared to a baseline where all other emissions were at 2011 levels), we estimated that reducing population exposures to PM2.5 would result in 1 (95% CI: 0 - 1) fewer premature death each year. Reductions in PM2.5 and O3 exposures would also result in fewer restricted activity days among adults [5 (95% CI: -3 – 95)] and fewer missed school days for children [27 (95% CI: -19- 582)]. Benefits of retiring the Comanche units were similar when emissions controls at Martin Drake are taken into account (Health Benefits Scenario 2). • For Health Benefits Scenario 3 (emissions at Martin Drake were “zeroed out”), we estimated that reducing population exposures to PM2.5 and O3 would result in 4 (95% CI: 2 - 5) and < 1 (95% CI: 0 - 1) fewer premature deaths each year, respectively. Reductions in PM2.5 and O3 exposures would also result in fewer restricted activity days among adults [10 (95% CI: 0 – 74)] and fewer missed school days for children [4 (95% CI: 2- 5)]. • For Health Benefits Scenario 4, we estimated that reducing population exposures to PM2.5 and O3 would result in 4 (95% CI: 2 - 6) and < 1 (95% CI: 0 - 1) fewer premature deaths each year, respectively. Among the largest annual health benefits are avoided asthma symptom days among children [16 (95% CI: -1 – 141) due to PM2.5 and 13 (95% CI: -348 - 972) due to O3] and minor restricted activity days among adults [69 (95% CI: 0 - 488) due to PM2.5 and 71 (95% CI: -31 - 750) due to O3]. We also estimated that, for Health Benefits Scenario 1, children in the study area would miss 77 (95% CI: -77 - 1180) fewer days of school each year due to lower O3 exposures. • Annual health benefits were lower for Health Benefits Scenario 5 compared to Scenario 4 due to the smaller change in exposure concentration after accounting for the control technologies installed at Martin Drake in 2016. For Health Benefits Scenario 5, we estimated that reducing population exposures to PM2.5 and O3 would result in 2 (95% CI: 1 - 3) and < 1 (95% CI: 0 - 1) fewer premature deaths each year, respectively. Other annual benefits under Health Benefits Scenario 2 included 2 (95% CI: -17 – 44) and 9 (-242 – 678) avoided asthma symptom days due to PM2.5 and O3 exposures, respectively; 28 (95%CI: -2 – 188) and 48 (95%CI: -16 – 513) minor restricted activity days due to PM2.5 and O3 exposures; and 53 (95% CI: -48 – 833) avoided school absences among children due to O3 exposures. • Monetized health benefits when both plants were “zeroed out” ranged from $4.2 million (95$2.1 million - $7.2 million) for Health Benefits Scenario 4 to$1.7 million (95% CI: $0.8 million – 3.2 million) for Health Benefits Scenario 5. Benefits tended to be smaller when only one plant was considered. In all of the analyses, the monetized impacts were driven by the value of avoided premature mortality. In addition, we found that ZIP codes with lower median incomes tended to receive a greater share of the health benefits of decreasing exposures to PM2.5 and O3 resulting from power plant shutdowns. This finding suggests that reducing emissions at the power plants could potentially alleviate some environmental justice concerns in the area

Perspectives on decision making amongst older people with end‐stage renal disease and caregivers in Singapore: a qualitative study

Background End‐stage renal disease (ESRD) is increasing both globally and in Asia. Singapore has the fifth highest incidence of ESRD worldwide, a trend that is predicted to rise. Older patients with ESRD are faced with a choice of haemodialysis, peritoneal dialysis or conservative management, all of which have their risks and benefits. Objective This study seeks to explore perspectives on decision making amongst older (≥70) Singaporean ESRD patients and their caregivers to undergo (or not to undergo) dialysis. Design Qualitative study design using semi‐structured interviews. Setting and participants Twenty‐three participants were recruited from the largest tertiary hospital in Singapore: seven peritoneal dialysis patients, five haemodialysis patients, four patients on conservative management and seven caregivers. Results While some patients believed that they had made an independent treatment decision, others reported feeling like they had no choice in the matter or that they were strongly persuaded by their doctors and/or family members to undergo dialysis. Patients reported decision‐making factors including loss of autonomy in daily life, financial burden (on themselves or on their families), caregiving burden, alternative medicine, symptoms and disease progression. Caregivers also reported concerns about financial and caregiving burden. Discussion and conclusion This study has identified several factors that should be considered in the design and implementation of decision aids to help older ESRD patients in Singapore make informed treatment decisions, including patients' and caregivers' decision‐making factors as well as the relational dynamics between patients, caregivers and doctors.This research was supported by the National Medical Research Council of Singapore (Grant Number: NMRC/HSRG/0080/2017), the Lien Centre for Palliative Care at Duke NUS Medical School and the National University Health System (NUHS) Singapore Population Health Improvement Centre (SPHERiC)(Grant Number: NMRC/CG/C026/2017_NUHS)

The Elderly Patient with End-Stage Renal Disease: Is Dialysis the Best and Only Option?

Singapore is facing an ageing population. This is reflected in the growing number of patients needing to consider starting dialysis in their golden years. In our review, we have found that there is a survival benefit for starting dialysis in our geriatric end-stage renal disease (ESRD) patient with low comorbidity. However, this comes at an expense of reduced quality of life, increased hospitalisation and reduced functional status. The decision to start or withhold dialysis in an elderly patient is a complex one and has to be considered on an individual basis with continuous discussions with the patient and loved ones. Advance Care Planning is a useful tool that can assist in this process

Global burden of mortalities due to chronic exposure to ambient PM2.5 from open combustion of domestic waste

Uncontrolled combustion of domestic waste has been observed in many countries, creating concerns for air quality; however, the health implications have not yet been quantified. We incorporate the Wiedinmyer et al (2014 Environ. Sci. Technol. https://doi.org/10.1021/es502250z 48 https://doi.org/10.1021/es502250z ) emissions inventory into the global chemical-transport model, GEOS-Chem, and provide a first estimate of premature adult mortalities from chronic exposure to ambient PM _2.5 from uncontrolled combustion of domestic waste. Using the concentration-response functions (CRFs) of Burnett et al (2014 Environ. Health Perspect. https://doi.org/10.1289/ehp.122-a94 122 https://doi.org/10.1289/ehp.122-a94 ), we estimate that waste-combustion emissions result in 270 000 (5th–95th: 213 000–328 000) premature adult mortalities per year. The confidence interval results only from uncertainty in the CRFs and assumes equal toxicity of waste-combustion PM _2.5 to all other PM _2.5 sources. We acknowledge that this result is likely sensitive to choice of chemical-transport model, CRFs, and emission inventories. Our central estimate equates to 9% of adult mortalities from exposure to ambient PM _2.5 reported in the Global Burden of Disease Study 2010. Exposure to PM _2.5 from waste combustion increases the risk of premature mortality by more than 0.5% for greater than 50% of the population. We consider sensitivity simulations to uncertainty in waste-combustion emission mass, the removal of waste-combustion emissions, and model resolution. A factor-of-2 uncertainty in waste-combustion PM _2.5 leads to central estimates ranging from 138 000 to 518 000 mortalities per year for factors-of-2 reductions and increases, respectively. Complete removal of waste combustion would only avoid 191 000 (5th–95th: 151 000–224 000) mortalities per year (smaller than the total contributed premature mortalities due to nonlinear CRFs). Decreasing model resolution from 2° × 2.5° to 4° × 5° results in 16% fewer mortalities attributed to waste-combustion PM _2.5 , and over Asia, decreasing resolution from 0.5° × 0.666° to 2° × 2.5° results in 21% fewer mortalities attributed to waste-combustion PM _2.5. Owing to coarse model resolution, our global estimates of premature mortality from waste-combustion PM _2.5 are likely a lower bound

Patient Decision Aid Development for Older Adults With End-Stage Kidney Disease in Singapore

10.1016/j.ekir.2021.08.027Kidney International Reports6112885-289

Discovery of new genes involved in curli production by a uropathogenic Escherichia coli strain from the highly virulent O45:K1:H7 lineage

Curli are bacterial surface-associated amyloid fibers that bind to the dye Congo red (CR) and facilitate uropathogenic Escherichia coli (UPEC) biofilm formation and protection against host innate defenses. Here we sequenced the genome of the curli-producing UPEC pyelonephritis strain MS7163 and showed it belongs to the highly virulent O45:K1:H7 neonatal meningitis-associated clone. MS7163 produced curli at human physiological temperature, and this correlated with biofilm growth, resistance of sessile cells to the human cationic peptide cathelicidin, and enhanced colonization of the mouse bladder. We devised a forward genetic screen using CR staining as a proxy for curli production and identified 41 genes that were required for optimal CR binding, of which 19 genes were essential for curli synthesis. Ten of these genes were novel or poorly characterized with respect to curli synthesis and included genes involved in purine de novo biosynthesis, a regulator that controls the Rcs phosphorelay system, and a novel repressor of curli production (referred to as rcpA). The involvement of these genes in curli production was confirmed by the construction of defined mutants and their complementation. The mutants did not express the curli major subunit CsgA and failed to produce curli based on CR binding. Mutation of purF (the first gene in the purine biosynthesis pathway) and rcpA also led to attenuated colonization of the mouse bladder. Overall, this work has provided new insight into the regulation of curli and the role of these amyloid fibers in UPEC biofilm formation and pathogenesis.IMPORTANCE Uropathogenic Escherichia coli (UPEC) strains are the most common cause of urinary tract infection, a disease increasingly associated with escalating antibiotic resistance. UPEC strains possess multiple surface-associated factors that enable their colonization of the urinary tract, including fimbriae, curli, and autotransporters. Curli are extracellular amyloid fibers that enhance UPEC virulence and promote biofilm formation. Here we examined the function and regulation of curli in a UPEC pyelonephritis strain belonging to the highly virulent O45:K1:H7 neonatal meningitis-associated clone. Curli expression at human physiological temperature led to increased biofilm formation, resistance of sessile cells to the human cationic peptide LL-37, and enhanced bladder colonization. Using a comprehensive genetic screen, we identified multiple genes involved in curli production, including several that were novel or poorly characterized with respect to curli synthesis. In total, this study demonstrates an important role for curli as a UPEC virulence factor that promotes biofilm formation, resistance, and pathogenesis