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PURGE final dissemination seminar - London, UK

took place on 23rd July 2014 in...

PURGE dissemination seminar - Beijing, China

took place on Friday 13th June 2014...

PURGE 3rd Consortium Management Meeting

took place on 27.-28. January 2014,...

Work Description

Project work summary (March 2014)


Context and objectives


There is growing evidence that policies to reduce greenhouse-gas (GHG) emissions can have direct and potentially large effects on population health. They are often, but not universally, beneficial.

These ancillary effects for health (sometimes referred to as health ‘co-benefits’) are important because they can provide an additional rationale to pursue mitigation strategies, and demonstrate opportunities by which population health may be improved while pursuing environmental objectives.

The PURGE project aims to add further evidence in this area by developing methods to quantify the positive and negative impacts on health and wellbeing of GHG reduction strategies in urban areas of Europe, China and India, so as to inform policy decisions in such areas as energy, housing/built environment, transport, and food.

The specific objectives may be summarized as follows:

• To define the critical policy choices for mitigation in selected settings in Europe, China and India, and the parameters within which those choices are constrained

• To delineate sets of specific interventions, tailored to local needs, which meet the demanding abatement trajectories at several future time points (2020, 2030, 2050)

• To quantify the changes in health-affecting ‘exposures’ and health behaviours that are likely to accompany those interventions and policies, and hence

• To quantify the health impacts (mortality and morbidity) associated with those policy choices

• To address important evidence gaps about the behaviour changes that are likely from selected mitigation measures, and about forms of economic influence on patterns of energy consumption

• To determine the costs and benefits to health of the mitigation measures examined from societal, household and health service perspectives

• To examine the implications of such evidence for policy decisions, in the context of uncertainty, taking account of both positive and negative potential impacts.

The project develops evidence using eight cities (four large established cities, and four smaller growing cities) with models of change for each city relating to one or more of the four sectors noted above: transport, electricity generation, housing and food.

Its evidence is expected to identify forms of greenhouse gas reduction strategy most likely to be beneficial to health, and to understand potentially adverse unintended consequences so that policies may be better informed to protect and promote health.

Description of work to date


The project is developing methods and evidence relating to the health impacts of greenhouse gas (GHG) reduction strategies in urban environments in Europe and Asia. 

This evidence is developed with respect to interventions in housing, food and agriculture, transport, and electricity generation.  Eight ‘case study’ cities have been chosen across four countries: the UK (London and Milton Keynes), Serbia (Belgrade and Nis), China (Beijing and Wuxi) and India (Delhi and Vishakhapatnam). Greenhouse gas abatement policies and targets up to 2050 (more limited for China) have been identified for these settings. Models of change relating to one or more of the four target sectors have been developed for each city.

Methods to quantify the impact of these scenarios on health have been developed using an integrated modelling framework applied first to the UK housing sector as the test case. This framework allows a flexible specification of intervention scenarios and assessment of the resultant changes in personal exposures in the indoor environment and associated health outcomes.  Similar methods have been developed for diet/agriculture and transport sectors. 

Initial sets of results not only indicate the potential for benefits to health of home energy efficiency interventions, but also potential trade-offs with interventions that reduce uncontrolled ventilation in dwellings. Without mechanical or purpose-provided ventilation, such interventions may have appreciable adverse impact on health through increased exposure to radon, particles of indoor origin, second hand tobacco smoke, mould and other pollutants.

Models of change in dietary patterns suggest that if UK diets were optimized to comply with WHO recommendations, an incidental reduction of 17% in GHG emissions could be achieved, with further reductions obtainable by modifying diets to contain fewer animal products and processed snacks and more fruit, vegetables and cereals. GHG reductions greater than 40% would require fairly radical and probably unpalatable change to consumption patterns. But the changes needed to achieve a 40% reduction would likely entail substantial reductions in mortality and morbidity especially from cardiovascular disease, cancer, and type II diabetes.

Other scenarios explore the improvements in population health through interventions that reduce outdoor air pollution or lead to more sustainable transport by increasing walking and cycling.

Evidence has also been assembled on medical treatment costs, the monetary values of lost productivity, losses of welfare and some values of mortality risk on adults and children to inform subsequent inclusion of costing data in the impact assessments.

The project has also gathered survey data (in Italy, Spain and shortly also in the Czech Republic) on choices in energy efficiency in the residential sector.  The results are relevant to energy efficiency policies and, for example, indicate that Italian tax credits have limited impact on the uptake of heating system upgrades but greater impact to stimulate investments in double glazing.

Finally, a database of selected cities representing low, middle and high income settings is being developed to help assess the potential for public health impacts of GHG reduction policies in urban areas of the target regions beyond the case study cities.

Use, impact and wider social implications 


The PURGE project will yield evidence on the health impacts in urban environments in Europe and Asia of greenhouse gas reduction strategies in the areas of transport, electricity generation, housing and food and agriculture. Its findings will:

(1) Broaden evidence on the forms of impact associated with GHG reduction to include health, which hitherto has received comparatively little attention in debates about the cost-benefit of ‘decarbonization’. It is expected that for many strategies, the net consequences for health will be positive, so adding to the rationale for an accelerated transition to low carbon (low GHG) economies, perhaps by helping to off-set some of the perceived economic costs.

(2) Provide evidence on the types of GHG reduction strategy within each sector that are likely to have the greatest health dividend.

(3) Yield more detailed evidence on both the positive and negative consequences for health of such strategies, so that policies and regulation may be better tailored to ensure opportunities for promoting health are maximized and protective steps can be taken to avoid unintended adverse effects for health.

Such evidence will be useful at various levels of policy: for international negotiations because of its bearing on the argument for wider (health-related) benefits of pursuing GHG abatement; at European and national levels to help guide policies that can capitalize on the opportunities for improving public health through GHG reduction; and within individual sectors, by providing evidence that can help inform regulation and guidance (for example, the setting of building standards) to protect and improve health.

By helping to shape policies that achieve needed transformation in energy use in major sectors of the economy, the findings of PURGE should make an important contribution to decisions that can help promote healthy, sustainable development of society: they will help to ensure that impacts on health are better understood and more visible to consider alongside economic factors.


Health is an important facet of sustainable development which has evident bearing equity – both within current society and across generations. The evidence from PURGE will therefore also contribute to understanding how health inequities and inequalities can be addressed through pursuit of environmental objectives.