Issue link: https://hi.iaq.net/i/670243
It will be noted that the estimate for PM 2.5 by COMEAP, presented above, is higher than the GBD estimate by about 20%. The COMEAP estimate is preferred here, because it is based on much finer-scale modelling. The two sets of results are, however, sufficiently close to provide a good level of corroboration. The GBD analysis addresses household air pollution in relation to emissions generated from solid fuel use, and particularly from crude, poorly ventilated stoves used in the developing world. Results for the UK for this source are negligible. There are further indoor air quality issues considered in the GBD work, some of which are highlighted towards the end of this chapter. 6.2.4 USEPA analyses USEPA has quantified health benefits of the US Clean Air Act of 1970 and subsequent legislation, including quantification of the costs and benefits of the 1990 Clean Air Act Amendments. 4 Estimated health impacts and associated economic benefits for the USA are shown in Table 3. Like most other analysis, the US work is focused on impacts related to PM and O 3 exposure, of which the PM effects are predominant. While the economic assessment is driven largely by mortality, the results showing change in incidence demonstrate a substantial burden on a wide range of morbidity endpoints. The costs of the US Clean Air Act Amendments are large, with an estimated net present value of $380 billion from 1990 to 2020. However, the overall benefits to society are considerably greater, estimated Table 3. USEPA results showing the estimated benefits of the US Clean Air Act Amendments for the USA in 2020. 4 Values are expressed in $million, price year 2006 Health effect Pollutant Incidence Value ($million) Mortality, attributed deaths* PM, O 3 230,000 1,800,000 Chronic bronchitis PM 75,000 36,000 Non-fatal myocardial infarction PM 200,000 21,000 Respiratory hospital admissions PM, O 3 66,000 1,100 Cardiovascular hospital admissions PM 69,000 2,000 Respiratory emergency room visits PM, O 3 120,000 44 Acute bronchitis PM 180,000 94 Lower respiratory symptom days PM 2,300,000 42 Upper respiratory symptom days PM 3,300,000 60 Asthma exacerbation days PM 6,700,000 130 Minor restricted activity days PM, O 3 140,000,000 6,700 Work loss days PM 19,000,000 2,700 School loss days O 3 8,600,000 480 Outdoor worker productivity O 3 Not applicable 170 *The mortality estimate shown includes effects on infants as well as adults. Source: USEPA, 4 Tables 5–7. © Royal College of Physicians 2016 83 6 The heavy cost of air pollution