PM10/PM2.5 Emissions and Effects
AUTHOR: Irene M Smith, Lesley L Sloss
DATE: October 1998
Particulate matter is emitted by a wide variety of sources such as road traffic, coal combustion, industry, wind blown soil and dust, and sea spray. Gaseous emissions such as SO2 and Nox are, to a varying extent, oxidised in the atmosphere to form secondary particulate matter. The mechanisms governing the pathways of stack emissions in the ambient air need to be understood in order to assess exposure of a given population to the varied component species of particulate matter. The smallest particles, PM10 and PM2.5, are of most concern and form complex mixtures of pollutants which vary in time and from place to place. PM2.5 are currently defined largely by sampling methods and not by chemical criteria although new monitoring programmes are starting to address this deficiency. Ambient air quality standards and monitoring networks ar discussed to identify important issues and potential problems with compliance. Emissions from coal-fired power stations are compared with those from other sources. Progress in the application of particulate.
SO2 and Nox emissions control technologies is examined, highlighting the achievements of specific plant configurations. Modelling techniques to ascertain the role of different emission sources are reviewed. Some regional characteristics of PM10 and PM2.5 concentrations as well as current and future trends are examined briefly. The many epidemiological studies which correlate health effects with particulate matter are summarised before a more detailed discussion of the limited information relating different constituents of particulate matter to actual biological responses in the human body. Major research needs are identified as a means of ensuring that new and proposed standards for particulate matter are workable.