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Particulate matter - PM10 and smaller

particulate matter of diameter less than or equal to 10 micrometers (microns)

SPRI Emission Reporting Threshold
10,000 Kg/yr Pollutant Emissions to Air
This sheet is a generic summary, designed to give the reader a basic level of background information about the substance in question. Great care has been taken to represent as effectively and correctly as possible the broad range of (not necessarily consistent) information which is available from a variety of sources. The reader must accept therefore that this sheet has no legal status and cannot be relied upon in any legal proceedings. SEPA disclaims any responsibility or liability whatsoever for errors and omissions in this sheet.
What is it?
Particulate matter is the term used to describe particles of soot (carbon), metals or inorganic salts. They vary in size and shape and are usually classified according to size categories: typically less than or equal to 10micron, PM10; and less than or equal to 2.5micron, PM2.5 (1 micron = 1 millionth of a meter).
What is it used for?
Particulate forms of many substances are used in a variety of industrial applications: steel processing, in cement works and in rubber manufacture. On a smaller scale, there are also many everyday uses such as in photocopier inks.
Where does it come from?
Particles of soot (carbon) are released from combustion processes (including vehicles), from waste incineration and from other industrial processes. Other types of particulates are released from construction and quarrying processes. Some particulates are released naturally from forest fires, volcanoes and from dust storms.
How might it affect the environment?
Local environmental damage is incurred from particulate pollution and includes damage to plants, materials and buildings. At a global level, recent research suggests that particulate pollution may contribute to global warming. It it thought that particulates may contaminate and reduce the reflective properties of other species in the atmosphere, which result in absorption rather than reflection of the suns rays and hence gives rise to a heating effect.
How might exposure to it affect human health?
Exposure to particulate pollution has been linked to adverse health effects. When inhaled, particles can be carried into the lung and exacerbate respiratory conditions such as asthma. There has also been concern that some particulates may be carcinogenic. Smaller particles are thought to pose the most serious threats as they can be carried deeper into the lungs.
What steps are being taken to limit the potential impacts?
In the UK (including Scotland) releases of particulate matter of less than or equal to 10micron (PM10) are controlled through the Pollution Prevention and Control regulations; and the National Air Quality Strategy, in which it is one of eight key substances being targeted. European Directives controlling emissions of particulates include those concerned with the assessment and management of ambient air quality (96/62/EC); and on setting air quality limit values for sulfur dioxide and related suspended particles (80/779).