Dirty Wood-Heaters

– by Dr. Dorothy Robinson, Woodsmoke.3sc.net 

The most health-hazardous air pollutant is PM2.5 (tiny particles less than 2.5 millionth of a metre in diameter) that cause 10 to 20 times as many premature deaths as the next worst pollutant (ozone).

PM2.5 penetrate the deepest recesses of our lungs.  As well as causing lung disease, PM2.5 can enter the bloodstream and transport the toxins in air pollution all round the body, causing inflammation, heart disease, cancers, dementia, genetic damage in babies, increased risk of childhood asthma, autism, reduced IQ when children start school and attention problems.

Not installing a new wood heater worth $82,000!!

Woodsmoke is reported to be worse than car exhausts.  New wood-heaters have real-life emissions of about 9.8 grams of PM2.5 per kg of firewood burnt. So a wood-heater burning Sydney’s average of 3.43 tonnes emits 33.6 kilograms of PM2.5 per year. With an 0.4 kg reduction in annual PM2.5 emissions worth an additional $980 on the cost of a new diesel, not emitting 33.6 kg of PM2.5 a year by not installing a new wood-heater burning an average amount of firewood, is worth a whopping $82,354!  Even if we could halve average emissions from a new heater, the estimated health cost would still exceed $40,000.

Wood-heating Industry opposed cleaner wood-heaters

The Senate Inquiry “Impacts on health of air quality in Australia” concluded that the failure to manage wood-heater pollution was“a failure of the technical committee to reach consensus within the meaning of Standards Australia’s rules, which according to the minutes supplied to the committee was a result of opposition from industry representatives.”  What a terrible tragedy that the health benefits of new vehicle standards are being undone by increased wood-heater use.

Largest source of PM2.5 pollution increasing due to regulatory failure

As shown in the NSW EPA graph (latest emissions inventory data – for the year 2008, published 2012), wood-heaters cause the lion’s share of Sydney’s wintertime health-hazardous PM2.5 emissions.Other major sources, road transport, industry, and non-road equipment are a much smaller fraction of the total.

Do people know that new wood-heaters emit more PM2.5 pollution (the most health-hazardous air pollutant) per year than 1,000 petrol or 200 diesel cars, or are they deceived by slick advertising?

PM2.5 pollution of 25 ug/m3 = everyone smoking 3 cigarettes per day = as damaging as current smoking rates 

At a recent Senate Inquiry hearing into Air Pollution Prof Higginbotham stated that breathing air at the standard of 25 ug/m3was equivalent to actively smoking 3 cigarettes.  One day in 2012, Armidale’s daily average PM2.5 from wood-smoke measured 65 ug/m3, as bad as forcing everyone – women, children, elderly residents, asthmatics and even babies – to smoke 7 cigarettes that day!  With tests on mice and bacteria showing woodsmoke causes 12 to 30 times as many tumours and mutations as the same amount of cigarette smoke, the total health effects of involuntarily breathing woodsmoke could be at least as serious as voluntary active smoking.

Health benefits of tackling woodsmoke pollution

Tackling wood-heater pollution has tremendous health benefits.  Deaths from respiratory diseases in winter fell by a whopping 28% and cardiovascular deaths by 20%, after Launceston’s $2.05 million program reduced use of wood-burning stoves from 66% to 30% of households.

Many woodsmoke pollution programs fail because local people do not know that new wood-heaters are almost as polluting as older models, or that the average brand-new wood-heater emits as many in PM2.5 in the first hour of operation as the average modern passenger car in an entire year.

Tandem health and climate benefits

Prof Piers Forster, lead author of the IPCC’s AR4 chapter Changes in Atmospheric Constituents and in Radiative Forcing (which sets out the scientific evidence that atmosphere changes are causing global warming) stated that “Reducing emissions from diesel engines and domestic wood and coal fires is a no-brainer as there are tandem health and climate benefits.

Prof Drew Shindell, lead author of the Anthropogenic & Natural Radiative Forcing chapter of the IPCC’s Climate Change 2013: The Physical Science Basis also chaired the UN Environment Program (UNEP) research that recommended phasing out log-burning heaters in developed countries to reduce global warming.

A most significant threat to our planet is the warming that will occur in the next 20 years, while we develop cost-effective alternatives, such as wind, solar (with storage) and electric cars running off solar electricity. All these are likely to provide cheaper, cleaner alternatives within 20 years to digging fossil fuels out of the ground.

Warming over the next 20 years (called short or near-term warming) is critical.  The UNEP report explains: “Near-term warming is pushing natural systems closer to thresholds that may lead to a further acceleration of climate change. For example, the melting of permafrost in the Arctic is releasing additional quantities of methane into the atmosphere, which in turn contribute to additional global warming“.

The Copenhagen target of limiting warming to 2°C will not be met unless we tackle near-term warming. In the first 20 years after emission, every kg of methane emitted from a domestic log-burning heater causes 88 times as much global warming as 1 kg of CO2, so, because of the substantial amount of methane they emit, log-burning heaters bring us nearer to exceeding the Copenhagen target than electric or gas heating for up to 12 similar houses.

Earlier assessments (when the prospect of exceeding the 2°C target seemed a long way off), concentrated on warming over 100 years.  This is no longer a sensible strategy.  Even biomass power plants (that produce no methane) are now considered likely to increase short-term global warming. Because of their methane emissions, domestic log-burning heaters are a much greater threat to the climate than biomass power plants.  Unfortunately, the peak wood heating industry body, who lied to the Senate Inquiry about their key role opposing new wood-heater standards, also lies to consumers by quoting inappropriate, out-of-date studies that ignore near-term warming, and glosses over the fact that much of Australian firewood production is from unsustainable sources.

Need new standard based on real-life operation

With no safe level of PM2.5 pollution, and the availability of cost-effective alternative such as reverse cycle airconditioners that (even when outside temperatures are as low as 7 degrees centigrade, can deliver 5.9 times as much heat to the living areas as they use in power), the best option is not to install any new wood-heaters until clean ones have been developed that meet a satisfactory health-based standard.

The Australian Lung Foundation recommends using alternative methods (to wood-heaters) for climate control.  The American Lung Association notes some of the dangerous chemicals in woodsmoke (dioxin, arsenic and formaldehyde”) and“strongly recommends using cleaner, less toxic sources of heat (than wood heating)”.

Brian Moench, president of Utah Physicians for a Healthy Environment wrote: ‘If you are not a smoker, burning wood is probably the greatest threat to your health as anything that you do. But it is also a threat to your neighbors’ health, as inappropriate as blowing cigarette smoke in the face of the passenger in the seat next to you. More than likely your neighbors are less than enthusiastic about sacrificing their health for your freedom to burn wood. A civilized society would suggest they shouldn’t have to.

Although this article focuses on Australian standards, the same problems apply in the U.S. Even after a $2.5 million program that replaced every old wood stove in Libby, Montana with a new one, this small town of 2,600 residents still had many days of totally unacceptable air quality.

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