Filters, particulates and deaths from emissions to air
Some waste incinerator emissions are trapped in filter bags, however the smallest particles (known as ‘PMs’ for ‘particulate matter’) are not. Information from a multi-national waste management company (Veolia) show that “…baghouse filter collection efficiency was 95-99% for PM10s, 65-70% for PM2.5s, and only 5-30% for particles smaller than 2.5 microns, even before the filters become coated with lime and activated carbon [from Howard C.V. The health impacts of incineration, with particular reference to the toxicological effects of ultrafine particulate aerosols, organo-chlorines and other emissions. Proof of Evidence submitted to East Sussex and Brighton and Hove Local Plan Public Inquiry, 2003].
L M Brown and his colleagues have pointed out that “long-term exposure to even low concentrations of fine particles may be associated with reduced life expectancy” [Brown L.M., Collings N., Harrison R.M., Maynard A.D. and Maynard R.L. Ultrafine particles in the atmosphere: introduction. Philosophical Transactions of the Royal Society of London A 358 (2000) 2563-2565].
Airborne particles are classified according to their size. Particles with a diameter of ≤ 10 microns (1 micron (1 µm) = 10-6 metre) are potentially dangerous because they are small enough to be drawn into the lung; such particles are designated PM10s. Particles with a diameter of ≤ 2.5 microns are more dangerous because they can be drawn deeper into the lung; they are designated PM2.5s. Even smaller particles are considered by many to be even more dangerous. The Environmental Protection Agency cites health studies indicating that particles smaller than 2.5 micrometers (PM2.5) are “the major contributor to serious health problems like respiratory illness and premature mortality” [http://www.crwi.org/textfiles/partem.htm].
There is a vast literature concerning the health effects of airborne particulate matter [Pope C.A. and Dockery D.W. Health effects of fine particulate air pollution: lines that connect. Journal of the Air and Waste Management Association 56 (2006) 709-742].
Whatever the technical details, everyone agrees that waste incinerators emit dangerous substances – the debate is around how much is emitted, and how dangerous these emissions are. The fact that research into incinerator emissions is still being conducted demonstrates that the scientific knowledge is far from complete, and that uncertainties remain over safety. A recent study (Aboh, et al. 2007) that looked into a medium sized city in southwestern Sweden, clearly identified their new modern incinerator as the single most significant source of PM2.5’s.
Another recent study (Mao, et al. 2007) found that the concentrations of PM2.5 and PM10 in the study area located downwind of the incinerator were significantly higher (between 220% and 700% higher) than the study area upwind of the incinerator. The study indicated that the air had “significant contamination by air pollutants emitted” from a waste incinerator, representing a public health problem for nearby residents, despite the facility being equipped with a modern air pollution control system.
Many studies, old and new, show that communities all around the world, living close to incinerators, even modern facilities, suffer higher rates of cancer and respiratory problems (e.g. http://tinyurl.com/y7dteo). The recently released Paris Appeal Memorandum, supported by the European Standing Committee of Doctors (representing 2 million doctors), urged a moratorium on building any new incinerators (www.artac.info/static.php?op=MemorandumParisAppeal.txt&npds=1).
It is now established beyond reasonable doubt that particulate air pollution causes death by various means. Research shows these include:
- Cardiovascular morbidity and mortality [Miller K.A., Siscovick D.S., Sheppard L., Shepherd K., Sullivan J.H., Anderson G.L. and Kaufman J.D. Long-term exposure to air pollution and incidence of cardiovascular events in women. New England Journal of Medicine 356 (2007) 447-458]
- Cardiopulmonary mortality [Pope C.A. Mortality effects of longer term exposures to fine particulate air pollution: review of recent epidemiological evidence. Inhalation Toxicology 19 (2007) 33-38]
- Respiratory, immunological, haematological, neurological and reproductive / developmental problems, sometimes with long time-lags between exposure and health effects [Curtis L., Rea W., Smith-Willis P., Fenyves E. and Pan Y. Adverse health effects of outdoor air pollutants. Environment International 32 (2006) 815-830]
- Every 10 µg/m3 increase in fine particulate levels was associated with a 4% increase in deaths from all causes, a 6% increase in deaths from cardiopulmonary illness and an 8% increase in lung cancer mortality [Pope C.A., Burnett R.T., Thun M.J., Calle E.E., Krewski D., Ito K. and Thurston G.D. Lung cancer, cardiopulmonary mortality, and long-term exposure to fine particulate air pollution. Journal of the American Medical Association 287 (2002) 1132-1141]
- There is particular concern about the effects of particulate pollution on infants. Increases in infant deaths from respiratory causes with a 10 µg/m3 increase in PM2.5s have been identified [Woodruff T.J., Darrow L.A. and Parker J.D. Air pollution and postneonatal infant mortality in the United States, 1999-2002. Environmental Health Perspectives 116 (2008) 110-115]
- A 10 µg/m3 increase in PM2.5s was related to a 5% increase in the risk for wheezing bronchitis [Pino P., Walter T., Oyarzun M., Villegas R. and Romieu I. Fine particulate matter and wheezing illness in the first year of life. Epidemiology 15 (2004) 702-708]
And sometimes these filter bags tear. The Sunday Herald (Scotland) discovered a major incident on 19 June 2001 which will lead to Dundee Energy Recycling Limited filing a formal report with Scottish Environment Protection Agency (SEPA). “A spokesman for SEPA said that a lot of black dust had poured from the incinerator for an hour after filter bags suddenly burst. The pollution emission dials went off-scale, so there were no readings for the amounts that were discharged. The incinerator was shut down and the operators are trying to find out why the filter bags, which were new, had failed”