§ Mr. Amess:To ask the Secretary of State for Environment, Food and Rural Affairs what estimate she has made of the number of tonnes of particulates saved from emission to the atmosphere in the UK as a result of accumulated switching from conventional automotive fuels to (a) LPG, (1)) CNG, (c) LNG and (d) hydrogen. [131715]
§ Mr. Bradshaw:Industry sources suggest there are around 100,000 vehicles currently running on LPG. It is not possible to precisely estimate the particulate matter emissions savings (a) because there are no measurements of particulate matter emissions from LPG fuelled vehicles and (b) there are no records of which fuel, petrol or diesel, was replaced. It is however estimated that around one third of LPG fuelled vehicles were converted from diesel. In this case, there would be savings of particulate matter emissions of around 130 tonnes per year. This is out of a total of 30,000 tonnes of PM emitted from UK road transport in 2001.
Industry sources suggest approximately 850 vehicles currently run on CNG/LNG. These are mainly heavy-duty vehicles that would otherwise be running on diesel. On the basis of this figure, it is estimated that 13 tonnes of PM have been saved in the UK by these conversions to CNG.
While comparatively small, these emissions savings contribute to improved air quality and help the UK move towards meeting its air quality objectives.
There are presently only a few prototype/demonstration vehicles in the whole of the UK running on hydrogen. Therefore, the particulate matter emission savings from converting to hydrogen are currently negligible. There is, however, long-term potential for significant particulate matter emissions savings by replacing conventional fuelled vehicles with hydrogen fuelled vehicles.
§ Mr. Amess:To ask the Secretary of State for Environment, Food and Rural Affairs what estimate she has made of the monetary value to the (a) environment and (b) human health of averting the emission of one tonne of particulates to the atmosphere. [131716]
§ Mr. Bradshaw:The external costs of air pollution is a subject where considerable research work is being undertaken to improve our scientific and economic understanding of the health and environmental damages of air pollution. This work is important to provide the evidence base on which policies are developed.
137WThe framework for estimating the external costs of one tonne of particulates to the atmosphere requires a detailed step-by-step analysis to assess the effect of emissions on local and regional air concentrations; quantify the health and environmental impacts using dose response functions and data on population exposed and value these health and environmental impacts in monetary terms where appropriate. Many factors including location of emissions will determine the extent of damages from a tonne of particulates.
In September 2001, the Interdepartmental Group on Costs and Benefits published "An Economic Analysis to Inform the Review of the Air Quality Strategy Objectives for Particles". This quantified a range of environmental and health effects arising from particulate emissions. Direct environmental effects of particles include damages from soiling of buildings. Evidence on the health effects of particles has been accumulating. Day to day variations in concentration of airborne particles are associated with day to day variations in a range of health end points. These include daily deaths, admissions to hospital for the treatment of both respiratory and cardiovascular diseases and symptoms among patients suffering from asthma. In addition, there is evidence from the United States that long-term exposure to particulate air pollution is associated with a decrease in life expectancy. In 2001, COMEAP (Committee on the Medical Effects of Air Pollutants) reviewed the evidence on the long-term effects of particles on mortality and concluded that it was more likely than not that a causal association existed between long-term exposure to particles and mortality. The IGCB Report took on board this advice in quantifying the long-term mortality effects of particles. However, the health benefits were not presented in monetary terms due to the uncertainties over valuation in the air pollution context where empirical studies are not yet available.