Health and Climate Change 2 Public health benefits of strategies to reduce greenhouse-gas emissions: urban land transport

Department of Epidemiology and Population Health, London School of Hygiene and Tropical Medicine, London, UK.
The Lancet (Impact Factor: 45.22). 11/2009; 374(9705):1930-43. DOI: 10.1016/S0140-6736(09)61714-1
Source: PubMed

ABSTRACT We used Comparative Risk Assessment methods to estimate the health effects of alternative urban land transport scenarios for two settings-London, UK, and Delhi, India. For each setting, we compared a business-as-usual 2030 projection (without policies for reduction of greenhouse gases) with alternative scenarios-lower-carbon-emission motor vehicles, increased active travel, and a combination of the two. We developed separate models that linked transport scenarios with physical activity, air pollution, and risk of road traffic injury. In both cities, we noted that reduction in carbon dioxide emissions through an increase in active travel and less use of motor vehicles had larger health benefits per million population (7332 disability-adjusted life-years [DALYs] in London, and 12 516 in Delhi in 1 year) than from the increased use of lower-emission motor vehicles (160 DALYs in London, and 1696 in Delhi). However, combination of active travel and lower-emission motor vehicles would give the largest benefits (7439 DALYs in London, 12 995 in Delhi), notably from a reduction in the number of years of life lost from ischaemic heart disease (10-19% in London, 11-25% in Delhi). Although uncertainties remain, climate change mitigation in transport should benefit public health substantially. Policies to increase the acceptability, appeal, and safety of active urban travel, and discourage travel in private motor vehicles would provide larger health benefits than would policies that focus solely on lower-emission motor vehicles.

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Available from: Graeme Lindsay, Sep 28, 2015
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    • "Recently, a number of studies have attempted to quantify the overall health co-benefits of replacing car travel with alternative transport (Macmillan et al., 2014; Maizlish et al., 2013; Rojas-Rueda et al., 2012). For instance, a UK study (Woodcock et al., 2009) projected the environmental and health benefits of various alternative transport scenarios for 2030 in London. The study indicated that over 500 premature deaths and over 7000 disability-adjusted life-years (DALYs) could be saved under alternative transport scenarios. "
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    ABSTRACT: Background: Motor vehicle emissions contribute nearly a quarter of the world's energy-related greenhouse gases and cause non-negligible air pollution, primarily in urban areas. Changing people's travel behaviour towards alternative transport is an efficient approach to mitigate harmful environmental impacts caused by a large number of vehicles. Such a strategy also provides an opportunity to gain health co-benefits of improved air quality and enhanced physical activities. This study aimed at quantifying co-benefit effects of alternative transport use in Adelaide, South Australia. Method: We made projections for a business-as-usual scenario for 2030 with alternative transport scenarios. Separate models including air pollution models and comparative risk assessment health models were developed to link alternative transport scenarios with possible environmental and health benefits. Results: In the study region with an estimated population of 1.4 million in 2030, by shifting 40% of vehicle kilometres travelled (VKT) by passenger vehicles to alternative transport, annual average urban PM2.5 would decline by approximately 0.4μg/m(3) compared to business-as-usual, resulting in net health benefits of an estimated 13deaths/year prevented and 118 disability-adjusted life years (DALYs) prevented per year due to improved air quality. Further health benefits would be obtained from improved physical fitness through active transport (508deaths/year prevented, 6569DALYs/year prevented), and changes in traffic injuries (21 deaths and, 960 DALYs prevented). Conclusion: Although uncertainties remain, our findings suggest that significant environmental and health benefits are possible if alternative transport replaces even a relatively small portion of car trips. The results may provide assistance to various government organisations and relevant service providers and promote collaboration in policy-making, city planning and infrastructure establishment.
    Environment International 01/2015; 74. DOI:10.1016/j.envint.2014.10.004 · 5.56 Impact Factor
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    • "Active travel, in particular active commuting, is associated with higher total physical activity [5,6] and physical wellbeing [7] and lower cardiovascular risk [8,9]. Over half of journeys in the UK are made by car [10], modelling suggests that increases in active travel and reductions in motor vehicle use would have public health benefits [11], and promoting the use of public transport can facilitate walking [12,13] and cycling [14]. "
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    ABSTRACT: Background Media content can increase awareness of, and shape interactions with, public health interventions. As part of a natural experimental evaluation of the travel, physical activity and health impacts of the Cambridgeshire Guided Busway, we analysed print and social media discourse and interview data to understand the nature of new transport infrastructure and how it was experienced. Methods Newspaper articles were systematically retrieved from the LexisNexis database and tweets were identified from an online archive. Interviews were conducted as part of the larger evaluation study with 38 adults. Inductive thematic analysis was performed and comparisons were drawn between datasets. Results The findings are discussed in relation to five themes. First, an understanding of the intervention context and how the intervention was experienced was developed through accounts of events occurring pre and post the busway’s opening. Second, the media captured the dynamic nature of the intervention. Third, the media constructed idealised portrayals of the anticipated busway which in some cases were contradicted by the impact of the busway on the existing context and people’s lived experiences. Fourth, differential media coverage of the intervention components suggested that a lesser value was placed on promoting active travel compared with public transport. Lastly, interview data provided support for the hypothesis that the media increased awareness of the busway and served as a frame of reference for constructing expectations and comparing experiences. Conclusions This analysis has contributed to the wider evaluation of the busway, helping to understand its nature and implementation and informing hypotheses about how the local population interact with the infrastructure by attending to the significance of representations in the media.
    BMC Public Health 05/2014; 14(1):482. DOI:10.1186/1471-2458-14-482 · 2.26 Impact Factor
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    • "An example of an adverse impact with a relatively simple causal pathway is increased pedestrian and cyclist exposure to road traffic injuries resulting from an increase in active transport (DiGuiseppi et al. 1997; Jarrett et al. 2012; Woodcock et al. 2009). In one analysis, estimated increases in morbidity and mortality from pedestrian and cyclist road traffic injuries in London (UK) were more than offset by decreases in disability-adjusted life years (DALYs) lost from physical inactivity and to a lesser extent air pollution (Woodcock et al. 2009), a finding reinforced by Lindsay et al. (2011). More complex, indirect pathways can also yield adverse impacts—for example, switching some agricultural production from food to biofuel feedstocks can have complex, recursive macroeconomic effects including shifts in prices of various food staples (Chakravorty et al. 2009). "
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    ABSTRACT: Climate change mitigation policy decisions are increasingly incorporating the beneficial and adverse health impacts of greenhouse gas emission reduction strategies. Studies of such co-benefits and co-harms involve modeling approaches requiring a range of analytic decisions that affect the model output. Our objective was to assess analytic decisions regarding model framework, structure, choice of parameters, and handling of uncertainty when modeling health co-benefits, and to make recommendations for improvements that could increase policy uptake. We describe the assumptions and analytic decisions underlying models of mitigation co-benefits, examining their effects on modeling outputs, and consider tools for quantifying uncertainty. There is considerable variation in approaches to valuation metrics, discounting methods, uncertainty characterization and propagation, and assessment of low-probability-high-impact events. There is also variable inclusion of adverse impacts of mitigation policies, and limited extension of modeling domains to include implementation considerations. Going forward, co-benefits modeling efforts should be carried out in collaboration with policymakers; include the full range of positive and negative impacts and critical uncertainties; include a range of discount rates; and explicitly characterize uncertainty. We make recommendations to improve the rigor and consistency of modeling of health co-benefits. Modeling health co-benefits requires systematic consideration of the suitability of model assumptions, of what should be included and excluded from the model framework, and how uncertainty should be treated. Increased attention to these and other analytic decisions has the potential to increase the policy relevance and application of co-benefits modeling studies, potentially aiding policymakers in efforts to maximize mitigation potential while simultaneously improving health.
    Environmental Health Perspectives 02/2014; 122(5). DOI:10.1289/ehp.1306744 · 7.98 Impact Factor
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