Meteorological drivers and mortality associated with O3 and PM2.5 air pollution episodes in the UK in 2006

In this study we examine the meteorological drivers resulting in concurrent high levels of ozone (O3) and particulate matter smaller than 2.5 andmu;m in diameter (PM2.5) during two five-day air pollution episodes in 2006 (1st - 5th July and 18th andndash; 22nd July) using an air quality model (AQUM) at 12 km horizontal resolution to simulate air pollutant concentrations. The resultant UK health burden associated with short-term exposure to simulated maximum daily 8-h O3andnbsp;(MDA8 O3) and daily mean PM2.5andnbsp;is estimated at the national and regional level. Both episodes were found to be driven by anticyclonic conditions with light easterly and south easterly winds and high temperatures that aided pollution build up in the UK. The estimated total mortality burden associated with short-term exposure to MDA8 O3andnbsp;is similar during the chosen episodes with about 70 daily deaths brought forward (summed across the UK) during the first and second episode, respectively. The estimated health burden associated with short-term exposure to daily mean PM2.5andnbsp;concentrations differs between the first and second episode resulting in about 43 and 36 daily deaths brought forward, respectively. The corresponding percentage of all-cause mortality due to short-term exposure to MDA8 O3andnbsp;and daily mean PM2.5during these two episodes and across the UK regions, ranges from 3.4% to 5.2% and from 1.6% to 3.9%, respectively. The attributable percentage of all-cause mortality differs between the regions depending on the pollution levels in each episode, but the overall estimated health burdens are highest in regions with higher population totals. We estimate that during these episodes the short-term exposure to MDA8 O3and daily mean PM2.5andnbsp;is between 36-38% and 39andndash;56% higher, respectively, than if the pollution levels represented typical seasonal-mean concentrations. This highlights the potential of air pollution episodes to have substantial short-term impacts on public health.</p

Future air pollution related health burdens associated with RCP emission changes in the UK

Intergovernmental Panel on Climate Change (IPCC) Representative Concentration Pathways (RCPs) are used to simulate future ozone (O3), nitrogen dioxide (NO2), and fine particulate matter (PM2.5) in the United Kingdom (UK) for the 2050s relative to the 2000s with an air quality model (AQUM) at a 12 km horizontal resolution. The present-day and future attributable fractions (AF) of mortality associated with long-term exposure to annual mean O3, NO2 and PM2.5 have accordingly been estimated for the first time for regions across England, Scotland and Wales. Across the three RCPs (RCP2.6, RCP6.0 and RCP8.5), simulated annual mean of the daily maximum 8-hr mean (MDA8) O3 concentrations increase compared to present-day, likely due to decreases in NOx (nitrogen oxides) emissions, leading to less titration of O3 by NO. Annual mean NO2 and PM2.5 concentrations decrease under all RCPs for the 2050s, mostly driven by decreases in NOx and sulphur dioxide (SO2) emissions, respectively. The AF of mortality associated with long-term exposure to annual mean MDA8 O3 is estimated to increase in the future across all the regions and for all RCPs. Reductions in NO2 and PM2.5 concentrations lead to reductions in the AF estimated for future periods under all RCPs, for both pollutants. Total mortality burdens are also highly sensitive to future population projections. Accounting for population projections exacerbates differences in total UK-wide MDA8 O3-health burdens between present-day and future by up to a factor of ~3 but diminishes differences in NO2-health burdens. For PM2.5, accounting for future population projections results in additional UK-wide deaths brought forward compared to present-day under RCP2.6 and RCP6.0, even though the simulated PM2.5 concentrations for the 2050s are estimated to decrease. Thus, these results highlight the sensitivity of future health burdens in the UK to future trends in atmospheric emissions over the UK as well as future population projections

Comparison of built environment adaptations to heat exposure and mortality during hot weather, West Midlands region, UK.

There is growing recognition of the need to improve protection against the adverse health effects of hot weather in the context of climate change. We quantify the impact of the Urban Heat Island (UHI) and selected adaptation measures made to dwellings on temperature exposure and mortality in the West Midlands region of the UK. We used 1) building physics models to assess indoor temperatures, initially in the existing housing stock and then following adaptation measures (energy efficiency building fabric upgrades and/or window shutters), of representative dwelling archetypes using data from the English Housing Survey (EHS), and 2) modelled UHI effect on outdoor temperatures. The ages of residents were combined with evidence on the heat-mortality relationship to estimate mortality risk and to quantify population-level changes in risk following adaptations to reduce summertime heat exposure. Results indicate that the UHI effect accounts for an estimated 21% of mortality. External shutters may reduce heat-related mortality by 30-60% depending on weather conditions, while shutters in conjunction with energy-efficient retrofitting may reduce risk by up to 52%. The use of shutters appears to be one of the most effective measures providing protection against heat-related mortality during periods of high summer temperatures, although their effectiveness may be limited under extreme temperatures. Energy efficiency adaptations to the dwellings and measures to increase green space in the urban environment to combat the UHI effect appear to be less beneficial for reducing heat-related mortality

Health effects of climate change (HECC) in the UK: 2023 report. Chapter 4. Impacts of climate change and policy on air pollution and human health

•Air pollution is one of the greatest environmental risks to public health in the UK and is associated with an estimated 29,000 to 43,000 deaths a year. Chapter 4 considers the relationship between climate change and outdoor air pollution and includes new analyses of the health burden from long-term and short-term exposure to air pollution. The chapter was led by expert scientists in the UK Health Security Agency (UKHSA), with contributions from experts in the University of Edinburgh, UK Centre for Ecology and Hydrology and University College London. •Key outdoor air pollutants include particulate matter (PM), nitrogen dioxide (NO2), and ozone (O3). Exposure to these is known to reduce life expectancy and is associated with a range of negative health effects, including respiratory and cardiovascular disease. People who live near busy roads are generally exposed to higher concentrations of air pollution. Some people are more susceptible to the health effects of air pollution including those with pre-existing cardiovascular and respiratory disease, young people, pregnant women, older people and low income communities. •Climate change will have an impact on air pollution. Changes in weather patterns, particularly temperature, rainfall and wind speed, are expected to have an effect on dispersal and concentrations of PM and O3. However, climate change mitigation measures that reduce emissions of greenhouse gases will help reduce air pollutants and lead to improvements in health outcomes. Evidence shows that emissions of air pollutants will be the dominant driver of air pollution concentrations over the coming decades. In this context, the analyses in the chapter focus on air pollutant emissions rather than climate change projections. •Future air quality in the UK will be determined by recent policy announcements and new legislation, such as the Environment Act 2021, the Environmental Improvement Plan 2023, and the Air Quality Strategy (England), the Environment (Air Quality and Soundscapes) (Wales) Bill, Cleaner Air for Scotland 2 strategy and Clean Air strategy for Northern Ireland. In 2018, the UK government published the 25 Year Environment Plan, which set out the framework and vision for reducing emissions of key air pollutants by setting or meeting legally binding targets. •Analysis of the impacts of air quality controls over the next 2 decades indicate that by 2050, exposure to PM2.5 will decrease by between 28% and 36%, and NO2 exposure will decrease by between 35% and 49%, depending on the region. By 2050, annual mortality attributable to the effects of long-term exposure to PM2.5 and NO2 is projected to decrease roughly by between 25% and 37% compared with a 2018 baseline, depending on future demographic change in the UK. Reducing emissions, therefore, results in benefits to population health. However, due to the complex chemistry in the air, as NO2 levels decrease, there can be local increases in O3 in urban centres, which may increase some harms to health. The analyses in the chapter show that annual estimated emergency respiratory hospital admissions associated with short-term Chapter 4. Impacts of climate change and policy on air pollution and human health 3 effects from O3 exposure are projected to increase by between 4% and 12% by 2050 from a 2018 baseline of 60,488, depending on demographic change. •Overall, these projections reflect significant improvements in outdoor air quality and associated reductions in the burden of long-term health impacts arising from recent and upcoming air quality controls, and the greater the efforts to mitigate emissions of air pollutants, the greater the improvement in air quality. •The results presented in the chapter have several implications for public health. Although air pollutant emission controls will reduce concentrations of some air pollutants (such as PM2.5 and NO2), there may be local increases in O3, which may be exacerbated during heatwaves. Therefore, provision of localised alerting and monitoring will become particularly important. Ensuring that public health professionals and other stakeholders have accessible and high quality information to provide health advice and raise awareness will continue to be important. •This chapter highlights several priority research gaps, including the need to: • develop modelling techniques that consider climate-driven changes in both pollutant emissions and meteorology at spatial resolutions sufficient to quantify exposures to improve health impact assessment projections • develop an evidence base estimating the economic benefits associated with improvements in health from air pollution reduction as a result of strategies to tackle climate change • undertake further work to consider the potential combined effects of air pollution and other environment stressors that may be affected by climate change, such as heat and aeroallergens • advance our understanding of how climate change-driven behavioural change could modify personal exposure to air pollution, such as increased time spent outdoors in warmer temperatures •The Department for Environment, Food and Rural Affairs (Defra), Department of Health and Social Care (DHSC) and UKHSA are undertaking a comprehensive review of how to communicate air quality information. The aim is to ensure members of the public, and vulnerable groups in particular, have what they need to protect themselves. UKHSA has also been developing an Air Pollution Exposure Surveillance (APES) vulnerability indicator which aims to indicate areas where population vulnerability to air pollution is elevated

Evaluating model parameterizations of submicron aerosol scattering and absorption with in situ data from ARCTAS 2008

Accurate modeling of the scattering and absorption of ultraviolet and visible radiation by aerosols is essential for accurate simulations of atmospheric chemistry and climate. Closure studies using in situ measurements of aerosol scattering and absorption can be used to evaluate and improve models of aerosol optical properties without interference from model errors in aerosol emissions, transport, chemistry, or deposition rates. Here we evaluate the ability of four externally mixed, fixed size distribution parameterizations used in global models to simulate submicron aerosol scattering and absorption at three wavelengths using in situ data gathered during the 2008 Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS) campaign. The four models are the NASA Global Modeling Initiative (GMI) Combo model, GEOS-Chem v9-02, the baseline configuration of a version of GEOS-Chem with online radiative transfer calculations (called GC-RT), and the Optical Properties of Aerosol and Clouds (OPAC v3.1) package. We also use the ARCTAS data to perform the first evaluation of the ability of the Aerosol Simulation Program (ASP v2.1) to simulate submicron aerosol scattering and absorption when in situ data on the aerosol size distribution are used, and examine the impact of different mixing rules for black carbon (BC) on the results. We find that the GMI model tends to overestimate submicron scattering and absorption at shorter wavelengths by 10–23 %, and that GMI has smaller absolute mean biases for submicron absorption than OPAC v3.1, GEOS-Chem v9-02, or GC-RT. However, the changes to the density and refractive index of BC in GC-RT improve the simulation of submicron aerosol absorption at all wavelengths relative to GEOS-Chem v9-02. Adding a variable size distribution, as in ASP v2.1, improves model performance for scattering but not for absorption, likely due to the assumption in ASP v2.1 that BC is present at a constant mass fraction throughout the aerosol size distribution. Using a core-shell mixing rule in ASP overestimates aerosol absorption, especially for the fresh biomass burning aerosol measured in ARCTAS-B, suggesting the need for modeling the time-varying mixing states of aerosols in future versions of ASP

Do schools differ in suicide risk? the influence of school and neighbourhood on attempted suicide, suicidal ideation and self-harm among secondary school pupils

&lt;br&gt;Background: Rates of suicide and poor mental health are high in environments (neighbourhoods and institutions) where individuals have only weak social ties, feel socially disconnected and experience anomie - a mismatch between individual and community norms and values. Young people spend much of their time within the school environment, but the influence of school context (school connectedness, ethos and contextual factors such as school size or denomination) on suicide-risk is understudied. Our aim is to explore if school context is associated with rates of attempted suicide and suicide-risk at age 15 and self-harm at age 19, adjusting for confounders.&lt;/br&gt; &lt;br&gt;Methods: A longitudinal school-based survey of 1698 young people surveyed when aged 11, (primary school), 15 (secondary school) and in early adulthood (age 19). Participants provided data about attempted suicide and suicide-risk at age 15 and deliberate self-harm at 19. In addition, data were collected about mental health at age 11, social background (gender, religion, etc.), and at age 15, perception of local area (e.g. neighbourhood cohesion, safety/civility and facilities), school connectedness (school engagement, involvement, etc.) and school context (size, denomination, etc.). A dummy variable was created indicating a religious 'mismatch', where pupils held a different faith from their school denomination. Data were analysed using multilevel logistic regression.&lt;/br&gt; &lt;br&gt;Results: After adjustment for confounders, pupils attempted suicide, suicide-risk and self-harm were all more likely among pupils with low school engagement (15-18% increase in odds for each SD change in engagement). While holding Catholic religious beliefs was protective, attending a Catholic school was a risk factor for suicidal behaviours. This pattern was explained by religious 'mismatch': pupils of a different religion from their school were approximately 2-4 times more likely to attempt suicide, be a suicide-risk or self-harm.&lt;/br&gt; &lt;br&gt;Conclusions: With several caveats, we found support for the importance of school context for suicidality and self-harm. School policies promoting school connectedness are uncontroversial. Devising a policy to reduce risks to pupils holding a different faith from that of their school may be more problematic.&lt;/br&gt

What are the health benefits of active travel? A systematic review of trials and cohort studies.

BACKGROUND: Increasing active travel (primarily walking and cycling) has been widely advocated for reducing obesity levels and achieving other population health benefits. However, the strength of evidence underpinning this strategy is unclear. This study aimed to assess the evidence that active travel has significant health benefits. METHODS: The study design was a systematic review of (i) non-randomised and randomised controlled trials, and (ii) prospective observational studies examining either (a) the effects of interventions to promote active travel or (b) the association between active travel and health outcomes. Reports of studies were identified by searching 11 electronic databases, websites, reference lists and papers identified by experts in the field. Prospective observational and intervention studies measuring any health outcome of active travel in the general population were included. Studies of patient groups were excluded. RESULTS: Twenty-four studies from 12 countries were included, of which six were studies conducted with children. Five studies evaluated active travel interventions. Nineteen were prospective cohort studies which did not evaluate the impact of a specific intervention. No studies were identified with obesity as an outcome in adults; one of five prospective cohort studies in children found an association between obesity and active travel. Small positive effects on other health outcomes were found in five intervention studies, but these were all at risk of selection bias. Modest benefits for other health outcomes were identified in five prospective studies. There is suggestive evidence that active travel may have a positive effect on diabetes prevention, which may be an important area for future research. CONCLUSIONS: Active travel may have positive effects on health outcomes, but there is little robust evidence to date of the effectiveness of active transport interventions for reducing obesity. Future evaluations of such interventions should include an assessment of their impacts on obesity and other health outcomes

A randomised controlled trial of supplemental oxygen versus medical air during exercise training in people with chronic obstructive pulmonary disease: Supplemental oxygen in pulmonary rehabilitation trial (SuppORT) (Protocol)

© 2016 Alison et al. Background: Oxygen desaturation during exercise is common in people with chronic obstructive pulmonary disease (COPD). The aim of the study is to determine, in people with COPD who desaturate during exercise, whether supplemental oxygen during an eight-week exercise training program is more effective than medical air (sham intervention) in improving exercise capacity and health-related quality of life both at the completion of training and at six-month follow up. Methods/Design: This is a multi-centre randomised controlled trial with concealed allocation, blinding of participants, exercise trainers and assessors, and intention-to-treat analysis. 110 people with chronic obstructive pulmonary disease who demonstrate oxygen desaturation lower than 90 % during the six-minute walk test will be recruited from pulmonary rehabilitation programs in seven teaching hospitals in Australia. People with chronic obstructive pulmonary disease on long term oxygen therapy will be excluded. After confirmation of eligibility and baseline assessment, participants will be randomised to receive either supplemental oxygen or medical air during an eight-week supervised treadmill and cycle exercise training program, three times per week for eight weeks, in hospital outpatient settings. Primary outcome measures will be endurance walking capacity assessed by the endurance shuttle walk test and health-related quality of life assessed by the Chronic Respiratory Disease Questionnaire. Secondary outcomes will include peak walking capacity measured by the incremental shuttle walk test, dyspnoea via the Dyspnoea-12 questionnaire and physical activity levels measured over seven days using an activity monitor. All outcomes will be measured at baseline, completion of training and at six-month follow up. Discussion: Exercise training is an essential component of pulmonary rehabilitation for people with COPD. This study will determine whether supplemental oxygen during exercise training is more effective than medical air in improving exercise capacity and health-related quality of life in people with COPD who desaturate during exercise. Trial registration: Australian New Zealand Clinical Trials Registry ACTRN12612000395831 , 5th Jan,201