Tag Archives: woodsmoke
– by Erin Voegele, October 14, 2016, Biomass Magazine
The U.S. Energy Information Administration has released the October edition of its Short-Term Energy Outlook, along with its Winter Fuels Outlook, predicting household expenditures on natural gas, heating oil, electricity and propane will increase this winter.
According to EIA, the National Oceanic and Atmospheric Administration predicts this winter, measured in heating degree days, will be 3 percent warmer than the previous 10-year average, but much colder than last winter, which averaged 15 percent warmer than the 10-year average nationally.
Within the report, the EIA notes the number of households using cord wood or wood pellets as the primary spacing heating fuel has increased 26 percent since 2005, reaching approximately 2.5 billion households in 2015. In addition, approximately 8 percent of households use wood as a secondary source of heat, making wood second only to electricity as a supplemental heating fuel.
[Read the opposing view to this opinion piece, “Renewability: Congress Confirms Biomass Energy is Renewable,” by Roger Sedjo and Stephen Shaler.]
– by Christopher D. Ahlers, Adjunct Professor, Vermont Law School
There has been increased public attention to the use of biomass as a means to address climate change. Recently, the Senate approved the Energy Policy Modernization Act, which would require the federal government to consider certain biomass projects as “carbon-neutral.” The bill attempts to circumvent the authority of the Environmental Protection Agency, which has been working on a policy relating to biogenic carbon dioxide emissions for over five years (biogenic emissions are those generated from the combustion of biomass, or biological materials such as plants and trees).
But the prevailing debate ignores the real problem of biomass. It overlooks the harm to public health.
– by Josh Schlossberg, The Biomass Monitor
Wood heating is on the rise. 2.7 million U.S. households, making up roughly 2% of the population, are projected to burn wood as a primary heating source over the winter of 2014-2015, a 3.9% increase from the previous year, according to the U.S. Energy Information Administration. Approximately 7.7% of households use a wood or pellet stove as a secondary heating source, based on 2012 census data.
In every state except for the balmy locales of Louisiana, Mississippi, Florida and Hawaii, wood heating has increased over the last decade, largely due to lower costs in comparison to oil and local sourcing opportunities.
Despite some recent advances in stove technology, wood heating still involves combustion, a process that emits air pollutants that have been linked to various health concerns. With the recent uptick in residential and industrial wood burning, it’s in the public’s best interest to be mindful of the risks that come from stoking up the stove.
1) Respiratory Problems
Residential wood burning “greatly increases” the amount of particulate matter (PM) in the air, pollutants smaller in diameter than a human hair, that can lodge deep inside the lungs, as well as enter the bloodstream and organs. Exposure to particulate matter can result in “aggravated asthma, chronic bronchitis, non-fatal heart attacks, and premature death,” according to the U.S. Environmental Protection Agency (EPA). PM can also trigger emphysema and strokes, with children, the elderly, sufferers of lung and heart disease, and those of lower income at highest risk.
A study by the California Air Resources Board reported that “wood smoke can cause a 10 percent increase of hospital admissions for respiratory problems among children, who are at most risk since their lungs are still developing.” Particulate matter can harm lungs during only a four hour exposure and cause even greater damage over the long-term.
The chance of premature death is 17% more likely in cities with high particulates compared to those with cleaner air, with every increase of 50 µg/m3 (microgram per square meter) of PM into the air resulting in a 6% spike in deaths and 18.5% increase in hospital admissions results, according to a study from the Harvard School of Public Health. In some cases, up to 90% of PM pollution can come from residential burning, with wood smoke regularly responsible for half of the California Bay area’s winter PM pollution.
Other health concerns related to wood smoke include “irritated eyes, throat, sinuses, and lungs; headaches; reduced lung function, especially in children; lung inflammation or swelling; increased risk of lower respiratory diseases; more severe or frequent symptoms from existing lung diseases.”
Health costs related to wood smoke particulate matter in the U.S. have been estimated at up to $150 billion a year.
Despite wood’s natural origin, wood smoke includes known carcinogenic chemicals such as benzene, formaldehyde, acetaldehyde, acrolein, and polycyclic aromatic hydrocarbons (PAHs), with studies demonstrating that wood smoke can cause lung cancer.
Wood burning is the largest source of PAHs in the US, with studies showing it to be the “worst contribution” to the air’s mutagenicity (likely to cause mutations in DNA, including cancer). One study concluded that burning two cords of wood can emit the same amount of PAHs as driving 13 gasoline powered cars 10,000 miles each at 20 miles/gallon.
Other studies have shown that wood smoke causes mouth, throat, lung, breast, and cervical cancer, in scientific literature compiled by Dr. Dorothy L. Robinson. Even more studies linking wood smoke and cancer can be found at the Australian Air Quality Group’s website.
3) Toxic Chemicals
Combustion of wood also re-releases heavy metals and radioactive pollution that have been absorbed by trees, in amounts significant enough that wood ash can qualify as hazardous waste under Europe’s definitions, if the standards for coal ash were applied to wood ash.
4) Worse Than Cigarettes
The health impacts of cigarettes was one of the biggest public health scandals of the 1980’s, resulting in smoking being banned in restaurants, bars, and other businesses and public places around the world. Despite the risks of cigarettes, you’re twelve times more likely to get cancer from wood smoke in comparison to an equal volume of second hand cigarette smoke, according to the EPA, cited in the Washington State Department of Ecology’s The Health Effects of Wood Smoke.
Wood smoke is thirty times more potent than cigarette smoke, according to “tumor initiation” tests done on laboratory mice, with another study showing that burning hardwood created three times the likelihood of tumors in mice than cigarette smoke, and more than fifteen times when burning softwood.
A fireplace burning for an hour puts out 4,300 times more PAHs than a pack and a half of cigarettes. Additionally, wood smoke “attacks” the cells of the body forty times longer than tobacco, with free radicals from wood smoke chemically active for twenty minutes, with those of tobacco lasting only thirty seconds.
Burning 1 kg of wood can emit more carcinogenic benzo[a]pyrene than 27,000 cigarettes and more formaldehyde than 6,000 cigarettes, according to Comparison of Toxic Chemicals in Wood and Cigarette Smoke, while another study calculated ambient air levels of benzo[a]pyrene from wood smoke the same as smoking two to sixteen cigarettes/day.
More comparisons of wood smoke to cigarette smoke are studied in Impact of Fuel Choice on Comparative Cancer Risk of Emissions,by Joellen Lewtas, Health Effects Research Laboratory, U.S. Environmental Protection Agency.
5) Exceeds Federal Standards
The World Health Organization maintains that exposure to fine particulate matter 2.5 (PM 2.5) shouldn’t exceed 25 μg/m3 (micrograms per cubic meter) over a 24 hour average, though the U.S. Environmental Protection Agency (EPA) has established a much laxer 35 μg/m3 under its National Ambient Air Quality Standards (NAAQS).
Yet even with the EPA’s leniency, a single wood stove can be responsible for a neighborhood exceeding even those levels, according to the American Lung Association. Since the beginning of the 2012-2013 winter stove season, the greater Fairbanks, Alaska area has logged 48 days that exceeded EPA standards. In November 2012, the air quality in the town of North Pole, Alaska, was measured as being twice as bad as Beijing’s, primarily due to wood smoke.
New Hampshire monitoring showed wood smoke violating PM standards by almost double the allowed levels in January 2009, with many communities in southwestern New Hampshire recording 35 μg/m3 and higher.
A study in New York — where up to 90% of the Particulate Matter measured came from wood combustion — found 26% of the population was exposed to wood smoke, with the poorer, more crowded and less-white populations receiving the highest levels of PM. Spikes of over 100 μg/m3 per cubic meter occurred during nighttime mobile monitoring, with the report linking such peaks to heart and lung problems, including heart attacks and asthma.
6) Smoke Enters Homes
It’s a common misconception that the only exposure to wood smoke occurs outdoors. However, a substantial amount of smoke actually enters the homes of wood burners, with particulate matter levels found to be 26% higher, benzene levels 29% higher, and PAHs 300% to 500% higher in the homes of wood burners, compared to those who use other heating sources. Another study estimated 70% of outdoor smoke can re-enter a home.
Those who don’t burn wood themselves, yet live in a neighborhood of wood burners, experience indoor particulate levels 50-70% of outdoor levels, according to a Seattle study, as wood smoke has the tendency to hang close to the ground and infiltrate homes, schools, and hospitals.
7) EPA Stoves Not Much Better
EPA stoves have improved somewhat upon conventional woodstoves. Instead of emitting 250 times more particulate matter than an oil or gas furnace, EPA stoves now emit eighty-five times more.
In Libby, Montana over $2.5 million financed the replacement of old wood stoves with EPA certified stoves, resulting in only a 28% reduction in emissions. Measures to further improve wood stove emissions are getting major pushback from the wood heating industry and some politicians.
8) Doctors Want Ban
Some medical professionals who have been studying the health impacts of wood smoke are concerned about the health ramifications, while others are calling for a phasing out of wood stoves. Dr. Brian Moench, president of Utah Physicians for a Healthy Environment, wants to see an end to residential wood burning. “We don’t have a lot of options,” he said. “We can accept our air pollution is not solvable, we can stop driving all our cars, we can tell industry to shut down, or we can stop burning wood.”
American Lung Association urges that the public “should avoid burning wood in houses where less polluting heating alternatives are available.”
9) Taxpayer Subsidized
Trends show more and more Americans burning wood to heat their homes, causing shortages of cordwood and pellets in some regions and the resulting price spikes. While an individual may choose not to operate a wood stove, a portion of his or her tax dollars may still subsidize those who do.
A $300 federal tax credit has been available to those purchasing new wood stoves or pellet stoves, with the policy set to expire in January 1, 2014, though industry groups claim an extension is possible. Eight states provide tax credits, rebates or deductions for wood heating, including Alabama, Arizona, Idaho, Maine, Maryland, Montana, and Oregon, with New York State offering a $1,000 tax credit for the purchase of a new pellet stove.
10) Alternatives to Burning
There are options for those seeking non-combustion technologies to heat their homes. Alternatives include ground source heat pumps, air source heat pumps, solar thermal, passive solar, and even experimental technologies, such as compost heating. No matter the heating source, the most basic and important step any homeowner can take to reduce energy demands is through insulation and other conservation and efficiency measures.
In some areas, you might not have a choice about whether you burn wood or not. Many states, such as Arizona, California, and Washington, enforce burn bans and restrictions, based on changes in air quality.
Several court cases, including one in Nebraska, have determined that a neighbor’s wood stove is a nuisance. A recently adopted bylaw in the County of Essex, Ontario, Canada states that one or more complaints in regards to smoke that has a “detrimental impact on the use and enjoyment” of property, will result in a cease and desist order barring future burning.
Montreal has taken things a step further, with plans to phase out wood stoves altogether by 2020.
– 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.