Issue link: https://hi.iaq.net/i/670243
Every breath we take: the lifelong impact of air pollution 6.4 Conclusions Despite actions undertaken over many decades, outdoor air pollution remains a major risk to health in the UK and other countries. These risks generate a burden to both mortality and morbidity, with a general consensus around the COMEAP estimate of 29,000 attributable deaths brought forward because of exposure to ambient PM 2.5 air pollution each year in the UK. Reported morbidity effects vary greatly in severity, from impacts that are seriously debilitating, such as COPD or cardiac events, to those that are less serious individually (eg 'restricted activity days' or 'symptom days'), but which affect a large number of people. The costs of these impacts, for welfare, healthcare and productivity, are truly substantial. Quantification of effects associated with exposure to NO 2 remains under discussion, although current indications are that PM 2.5 and NO 2 combined will bring forward around 40,000 attributable deaths annually. Over time, it is to be expected that the costs of controlling air pollution will rise, as the cheapest measures, including efficiency improvements that save money by reducing energy costs, are fully implemented. At some point, then, it is to be expected that the costs of reducing emissions will exceed the benefits gained. However, analyses for the European Commission, USEPA and others suggest that sufficient inexpensive measures remain available to justify continued action. In part, this reflects new understanding of the sources of pollution, with sources that have in the past attracted little attention now being considered important enough to be taken into account. A good example concerns emissions of ammonia from agriculture, which are linked to the formation of secondary sulphate and nitrate particles, an important part of the mixture of pollutants that together form PM. Most measures for reducing emissions of greenhouse gases (eg CO 2 ) also have benefits for reducing emissions of local and regional air pollutants. The 'co-benefits' so generated are substantial and, in some cases, sufficient on their own to justify the abatement measures, irrespective of resulting climate benefits. This results from the two types of pollutant sharing a major common source, the combustion of fossil fuels. In contrast, some measures for control of greenhouse gases may have a negative impact on air quality. Combustion of biomass fuel, for example, which is commonplace in middle- and lower-income countries, has the potential to increase emissions of fine particles, especially where the biomass is burned indoors for domestic heating and cooking. From this limited review of the health effects of indoor pollutants, it has been shown that they cause, at a minimum, several thousands of deaths per year in the UK, and are associated with healthcare costs in the order of tens of millions of pounds. A more systematic approach to the quantification of the effects of indoor air pollution would be beneficial, not least as this is where people in the UK spend most of their time. 6.5 References 1 ExternE (1995) Volume 2: methodology. Method for estimation of physical impacts and monetary valuation for priority impact pathways. ExternE: Externalities of Energy. www.externe.info/externe_d7/?q=node/37 [Accessed 15 December 2015]. 2 Committee on the Medical Effects of Air Pollutants. The mortality effects of long-term exposure to particulate air pollution in the United Kingdom. London: Health Protection Agency, 2010. www.gov.uk/government/ publications/comeap-mortality-effects-of-long-term-exposure-to-particulate-air-pollution-in-the-uk [Accessed 30 November 2015]. 3 Committee on the Medical Effects of Air Pollutants. Statement on the evidence for differential health effects of particulate matter according to source or components. London: Health Protection Agency, 2015. www.gov.uk/ government/publications/particulate-air-pollution-health-effects-of-exposure/ [Accessed 2 April 2015]. 90 © Royal College of Physicians 2016