Breaking science news: Yak dung burning pollutes indoor air of Tibetan households

From Emory Health Sciences, and the Department of Obvious Science, comes this press release that speaks for itself.

yak-dungTibet, the highest region on Earth and one of the most remote, is associated with vivid blue skies and the crystal clear air of the Himalayas. During the long cold season, however, the traditional nomadic people spend much of their time in snug dwellings where they cook and stay warm by burning yak dung. Their indoor air can be filled with dangerous levels of fine particulate matter, including black carbon, a new study finds.

The journal Atmospheric Environment published the research, led by Eri Saikawa, an assistant professor in the Department of Environmental Sciences at Emory University and in the Department of Environmental Health at the Rollins School of Public Health.

“Indoor air pollution is a huge human health problem throughout the developing world,” Saikawa says. “In a cold region like Tibet, the impact on individuals could be even greater because they spend so much time indoors and try to keep their homes as air tight as possible.”

Globally, the World Health Organization (WHO) estimated that 4.3 million people died prematurely in 2012 due to indoor air pollution from traditional stoves, fueled by coal, wood, dung or crop waste. In comparison, WHO estimated that outdoor air pollution was linked to 3.7 million deaths that year.

Tibet is situated on a plateau northeast of the Himalayas in China. For centuries, nomadic people there have herded yaks, large, long-haired relatives of cattle. Yaks work as pack animals and supply meat, milk, and fiber for fabrics. They also generate heating fuel in the form of dung.

Previous studies had looked at indoor air quality in Tibet during the summer season. Saikawa and her team wanted to investigate indoor emissions during the colder months.

In March of 2013, Qingyang Xiao, a graduate student in Rollins School of Public Health, traveled to the Tibetan region of Nam Co (which means “heavenly lake”) to gather the data. About 4,500 residents live in the region, at an altitude of 4,730 meters.

Xiao used battery powered aerosol monitors to measure indoor concentrations of fine particulate matter, or particles 2.5 micrometers in diameter or smaller, which consists mainly of black carbon and organic carbon. She recorded the measurements in six households with different living conditions and stove types. Yak dung was the main fuel for cooking and the only fuel for heating.

The results showed that the average concentrations for black carbon and fine particulate matter were nearly double those reported by some similar studies of households in areas of lower altitude and warmer climates, such as India and Mexico.

The Tibetan homes included four traditional tents and two simple stone houses. Both the tents and the houses had only one room where all of the family members slept, ate and cooked.

Three of the families used traditional open stoves without chimneys, and three had added chimneys to their stoves. A simple house with a chimney had the lowest indoor concentrations. This household lived on tourism and used liquefied petroleum gas (LPG) for cooking.

However, a stone house with a chimney had the highest black carbon concentrations.

“That was surprising,” Saikawa says. “It shows that it is misleading to think that having a chimney will always improve the situation, unless you can be sure that the home is ventilated correctly and that you have proper air flow within a dwelling.”

Xiao also surveyed members of 23 households on energy use and awareness of indoor air pollution. The families said they spent an average of 16 hours a day indoors during the colder months of the year.

Seventy percent of those surveyed said that they were aware of the health problems associated with indoor air pollution, and some of them did not have the economic means to purchase a chimney. (The average annual income per household is less than $900 a year, and a chimney costs around $60.)

The moisture content of the yak dung is another key factor in the emission levels, Saikawa says. After a rain or snowfall, the piles of uncovered dung are moist, leading to incomplete combustion and more emissions of fine particulate matter due to increased organic carbon by smoldering.

“It’s a complicated issue,” Saikawa says. “It’s much more than just a science problem. You have to understand how people live if you want to help find solutions to improve their lives.”

The Emory research team, including students from environmental sciences and the Rollins School of Public Health, is expanding on the small sample of households in this initial study. They are investigating indoor emissions in other areas of Tibet and plan to link these measurements to a biomarker study based on blood samples of people living in the households.

Saikawa, a specialist in atmospheric chemistry, is also studying levels of black carbon emissions in the outdoor environment generated by the burning of biomass fuels like yak dung.

Black carbon absorbs heat in the atmosphere and reduces the ability to reflect sunlight when deposited on snow and ice. Its impact is greatest at high altitudes. “Black carbon emissions from burning biofuel such as yak dung have not been quantified before in the atmosphere of the Himalayas,” Saikawa says. “We know that many Himalayan glaciers are melting rapidly, and our work suggests that more black carbon is getting deposited on them than previously thought.”

She hopes to eventually work with Georgia Tech engineer Jonathan Colton to develop gasifier cook stoves that would burn yak dung in a more efficient matter, producing fewer emissions. The stove would need to be portable, to suit the nomadic way of life, affordable for the Tibetans and simple to maintain.

“We want to use our data to make the world a better place,” Saikawa says. “The ultimate goal is to reduce pollution from biomass fuels in ways that benefit human health and reduce the climate impact.”

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129 thoughts on “Breaking science news: Yak dung burning pollutes indoor air of Tibetan households

    • This is news ?? I thought cow dung was the traditional renewable clean green free energy resource of India.
      Question is: Do the stoves burning Yak dung have a habit of blowing up like the Indian cow dung ones do. Seems like a lot of house wives in India get burned to death by their exploding kitchen stoves.
      There must be some other indoor animal detritus burning civilizations that also might get black lung disease.
      How about Inuit burning walrus blubber in their igloos with the lid on. They must be breathing sooty air too.
      You have to do scientific research to discover that burning crap, is unhealthy ??

      • The specific problem in Tibet is that you do not have very many trees to use as firewood. Their burial customs are often what is known as “Sky Burial” http://en.wikipedia.org/wiki/Sky_burial for that reason. With little firewood they cannot cremate most folks, with a frozen and rocky soil you can’t bury them either. Bottom line is that you put them out for the vultures (known as sky chariots locally btw) to deflesh. Given that they believe in samsara, the body means little after death. Various religious objects are made out of the skeletons to remind people of the impermanence of their present existence.
        Bottom line, you use what you got. Got Yak and need to keep warm? Go for it.

      • “””””…..
        ShrNfr
        January 16, 2015 at 3:45 pm
        The specific problem in Tibet is that you do not have very many trees to use as firewood. …..”””””
        Well you won’t get any argument from me on that front. Too bad those people are also enslaved in their own country. Another case, where we “failed to notice what was going on.” We are doing a lot of that lately.
        g

      • I would think that another variable that would effect efficient combustion of most things, including dung, would the the altitude in a place like Tibet. Isn’t that what were really talking about here for a stove? An apparatus that will:
        A. Increase the efficiency of combustion there by producing more heat per unit of fuel and thus decreasing the consumption of fuel burned per BTU produced and thus minimizing the unburned elements/smoke.
        B. Divert what gases/smoke that is produced away from the users/living area.

      • ShrNfr.
        It makes you wonder if the religious idea of not worrying about the flesh evolved because they couldn’t do anything about it. A religious reason evolving from a practical one.

      • The “exploding kitchen stoves” are kerosene stoves, not “dung” stoves… Kerosene, locally known as “matti tel” (mud oil, a translitteration of petro-oleum), or even “Krishna oil” (kerosene sounds a little bit like Krishna) in some areas, needs to be pumped up to squirt onto a red-hot metal ring to get ignited. It smells the same as if you were standing behind a jet at an airport. Not sure whether it’s any healthier than burning dung…

      • @ rah: January 16, 2015 at 5:13 pm
        Yup, me thinks your thinking is correct, to wit, ….. quoting article:

        About 4,500 residents live in the region, at an altitude of 4,730 meters (15,518 feet).

        At an altitude of 15,518 feet, ….. the big question is, ……. does one think the burning of Yak dung is a “black carbon” problem …. or an “oxidation” problem?

    • Rinse and repeat?

      Abstract – September 2009
      Total suspended particulate matter and toxic elements indoors during cooking with yak dung
      Many herders in the Tibetan Plateau still inherit the traditional lifestyle, including living in tents and burning yak dung for fuel. This short correspondence reports a pilot study on indoor air quality in the nomadic tents in the Nam Co region, inland Tibetan Plateau. The results showed very high concentrations of total suspended particles (TSP), averaging at 4.45 mg m−3 during the cooking/heating period (with daily value of 3.16 mg m−3). Elevated concentrations of toxic element Cd, As and Pb were also found within the tents, averaging 3.16 μg m−3, 35.00 μg m−3, and 81.39 μg m−3 for a day, respectively, which were not only far higher than those of WHO indoor air quality guidelines, but also more than 104–106 times higher than the outdoor air level in the Nam Co area. The study raises serious concerns over the health of Tibetan herders following their long-term exposure to the tent air.
      http://dx.doi.org/10.1016/j.atmosenv.2009.06.015

  1. The only catch phrase they left out was: “It’s worse than we thought!”
    A trip to an exotic places to ‘discover’ the blatantly obvious….. AKA boondoggle of the highest order…..Here’s where a model might have actually been useful.

  2. Meanwhile, we are constantly being told by Big Brother that we need to make our homes 100% air tight to save energy and rescue the gay baby whales from being steamed alive in the hotting-up oceans.

    • It’s been said that up to 30% of your heating energy is lost through unwanted exfiltration.
      As Joseph Lstiburek says; “build tight and ventilate right.”. His science seems sound, and he’s practical too.
      “gay baby whales”…who knew?

      • In the UK they now have air testing of new houses to ensure they are airtight.
        Having discussed this and other green building policies with the government department which produces the building regulations (building code) I wonder at the competence, or at least the commonsense, of some of the people involved.
        This is roughly what I was told 3 years ago :
        Houses should be airtight to reduce heat loss – but they know that leads to serious condensation problems (a major cause of mould growth and associated severe ill health).
        Mechanical ventilation can remove moist air and bring in fresh air – but neither that nor heat exchangers to reduce heat loss are a requirement even though air tightness is enforced to prevent heat and thus energy loss and waste !
        Air conditioning should be avoided to reduce energy consumption and CO2 emissions – even though mechanical ventilation will on a hot day bring in air which can be 30 deg C making the house uncomfortably hot and on a cold day, cool it dramatically.
        Windows which must be airtight must also incorporate ‘trickle vents’ which allow an airflow through the ‘airtight’ window ……… as I said at the time ‘so you mean the windows are the same as old fashioned windows with drafts ‘ after a slight pause the answer was “yes I suppose you could put it that way”.
        As an aside I recently did the calculations, using UK government data. to compare CO2 emissions from two different forms of heating. Ground or air source heat pumps are promoted to reduce energy use and reduce CO2 emissions. I was intrigued to find that when you include the power loss from resistance through the elecricity grid that a heat pump produces slightly more CO2 emissions per therm of heat generated than does an on-site gas boiler.
        Another odd calculation I did was UK based where it is standard practice for most meat products in supermarkets and stores to contain added water. This can be as much as 15% by weight although more normally is just below 10% where the water content labelling regulations come into force (above that level the actual water content by weight must be displayed on the labelling).
        It clearly benefits sellers to sell meat and bacon by weight when the consumer is buying some very expensive water – although they always counter this by claiming the consumer wants wet meat’ !
        I ran come calcs using government figures for annual sales of various packaged meat products which typically contain added water to see what the energy use, and thus CO2 emissions, were in boiling off this water during the cooking process. The outcomes were significantly large in terms of energy use and the resulting CO2 emissions – I didn’t take into account the energy use in transportation and distribution of all this water but it will not be an insignificant amount.
        The UK Department of Energy and Climate Change (DECC) weren’t in the least interested in any of this or looking into it further despite them being about as warmist as it is possible to get. I am going to play with this again in the next month or two using current figures to come up with a figure for both cooking and transportation.

    • Was speaking with a contractor this morning up here in Northern Vermont. Lately they’ve been virtually shrink wrapping new stick frame construction and applying concrete clapboards. Looks nice. I asked Tom if that didn’t just create a house as a chimney. He said he was more worried about the place not being able to breath.
      I’ve got an 1850’s post and beam farmstead right down the road. Been working on it for over 20 years – new windows, straight grain cedar clapboards from British Columbia, insulation . . . and despite my work, it breathes just great (wife wants tighter buy hey). Tonight it is headed again into minus double digits F and we’re burning wood. Our daughter who is asthmatic never has breathing trouble here, but is uncomfortable in appt in Burlington that seems tight.
      I am doing my level best to release gold old fashioned CO2 into local atmosphere.
      Have a great weekend and it is good to read a piece with actual sampled from the world data – small n, not sure how representative . . . but real.

      • Bubba Cow – I am asthmatic and live in a home which has only wood heat here in northeastern California. I only get asthma during the summer when there is no wood burning in the wood stove.

      • Radon gas is a big concern in much of the country. I have a very low HVAC consumption, even though my circa 1949 house leaks air, mainly by closing off unused rooms, and keeping thermostat at 66 (winter) or 76 (summer). The worst cracks are taped over in winter. I like that there is some “exfiltration” especially when there a good supply of chili laid in. What bothers me more the air incursion is noise incursion – the main attraction for tight, double-pane windows is sound dampening.

      • Here in Michigan we built new. I sealed up everything tight by followed behind the framing crew. Stopping airflow up high reduces the stack effects, air won’t come in low if it can’t go out high. We designed it to be pretty efficient to heat & cool. Bath exhaust fans are automatic, delay after showers. Passive makeup air, hasn’t had any issues relating to chili. I adjust the inlet in the winter to maintain ~30% RH.
        We have low temperature radiant floor heat, and keep the core areas at 73F. It sounds hot, but it’s very comfy, especially the tile, and no air blowing either. The colder the outdoor, the warmer the water gets that feeds the floors. It maxes out at 105F when it gets close to 5F outside, I love the cold now. Radon venting was required by code. Dense pack cellulose and good windows make it hard to tell when it’s storming out.

      • @ Bubba Cow – I agree wholeheartedly with the per se “shrink wrapping” of a house or home ….. but not if the per se “shrink wrap” is applied to the exterior surface prior to the “siding” material being installed. That is a guaranteed way to be “trapping” moisture in exterior/outside partitions.
        I also completely renovated a large 2-story “post and beam” farmstead in the early 1970’s …. only mine was circa 1862 and located in upstate New York (Herkimer County).
        I stripped the interior to the “bare” studding, including the ceilings on both floor. I then installed the 3” foil-backed “pink” insulation between the studding of all outside walls and in the upstairs ceilings. I then per se, “shrink wrapped” it on the inside by tightly stapling 5 mil clear plastic sheeting ….. from floor-to-ceiling, all around the exterior walls and across the upstairs ceilings. 5/8” Imperial board and “skim-coat” plaster was then applied.
        Thus my house was well insulated against those “howling” winter winds and -25 F to -35 F winter temps. And all those exterior walls could “breathe” just fine, without trapping any moisture, whenever the outside temperatures changed. And the couple that now owns it tells me they can also hear those “post n’ beam” joints a creaking n’ a groaning when the wind really gets ta “huffin n’ a puffin”.
        The only purpose the “shrink wrap” or plastic sheeting serves ….. is to STOP the airflow thru the walls, so, when applied to the “inside” it also serves as a “vapor barrier” instead of a “vapor trapper”.
        [Be aware the shrink wrap must be applied differently (often reversed from the above) for warmer, more humid climates with near-constant A/C needed; or eliminated entirely in favor of plain (unwrapped) insulation for half heated, half air-conditioned climates. .mod]

      • The other night I was watching “Whale Wars” on Animal Planet, and all I could think of was; Man I bet that’s good eats! I don’t have a dog in the fight, but ramming big boats with smaller boats didn’t seem all that smart of an idea to me.

  3. “In a cold region like Tibet, the impact on individuals could be even greater because they spend so much time indoors and try to keep their homes as air tight as possible.”
    So their other option is to be outdoors or keep the windows open, and freeze to death. But at least their frozen lungs are clean!

    • Actually, the part of the report that surprised me was that when its -20C they still go out about 8 hours a day! What are they doing out there?!

      • Well, a lot of them are yak herders (that’s where the Yak dung comes from). Hard to be that without going outdoors.

  4. …and do we really “know that many Himalayan glaciers are melting rapidly?” Or is that just received gospel of the Church of AGW?

  5. “Breaking science news: Yak dung burning pollutes indoor air of Tibetan households”
    I see an opportunity:
    develop non-polluting Yak dung.

  6. At least they appear to be making an effort to improve the situation, by developing a cheap gasifier stove. This is unusual behaviour for eco-types, who usually never attempt to do anything remotely useful.

    • Eric Worrall
      At the UK’s Coal Research Establishment (CRE) in the 1980s we devised and perfected the downdraft stove which consumes its own smoke.
      The problem is not the lack of needed technology. The problem is lack of money to adopt the available technology.
      Importantly, if the Tibetan people were sufficiently affluent then they would not need to burn dung. Nobody likes to live in a polluted environment, and everybody pays for the systems to reduce/prevent pollution of their living space when they can.
      Richard

      • Courtney, the solution is of course what feeds and warms people here – individual freedom supported by defense and justice systems.
        Tibet is not free, and herders may not be technically sophisticated (though hopefully they have evolved methods of raising their animals including resisting cold weather, and of making shelter for themselves. (The “Plains Indians” of North America had animal skin tents designed for transport (usually called “tipi” pronounced “teepee”).
        The tipi was optimized for travel – long poles that could be hold a bundle of coverings and be drug behind a human or – after the Spaniards arrived, a horse. (In Yamal people used a similar structure, with reindeer as the beasts of burden.) Other tribal people around the world had lower dwellings, including Inuit (the igloo is a temporary shelter for hunting parties) and the wikiup/wigwam in parts of North America, and more sturdy structures where people weren’t nomadic. All have the challenge of getting rid of the smoke.
        Some tipis and other skin-covered structures had double walls as a method of smoke control – it’s tricky, as an opening at the top lets rain and snow in. Someone in a WUWT thread described what they are like to live in – uncomfortable by our standards.
        The double wall also helped insulate and reduce unwanted drafts. A deluxe dwelling may have had an inner and outer room, the inner for sleeping. Where dogs were kept, as in the Arctic but sometimes further south, they’d sleep in the outer room. Similarly in Mongolia with sheep, but in a spartan dwelling all cuddled together.
        The Tibetan herders may just want to stay out there and be left alone – unlikely in Communist China.
        Or there may be income opportunities – for example, people in the Yamal area of Russia farm small caribou (called “reindeer” in the eastern hemisphere). But that depends on enough vegetation to produce for more than their own use. This thread indicates some are earning income from hosting tourists, as IIRC are some herders in Mongolia. I am skeptical there is much potential in that.
        The benefits of good energy are among the topics covered in Alex Epstein’s book “The Moral Case for Fossil Fuels”.

      • Sketchley
        You say to me

        Courtney, the solution is of course what feeds and warms people here – individual freedom supported by defense and justice systems.

        No. The use of fuels warms people and sufficient food supplies feed people: abstract concepts don’t.
        China has been totalitarian for thousands of years and under several different governments. It will require more than one generation to change such a strongly established culture.
        Richard

    • Worrall,
      There are charities who emphasize actually helping people in practical ways. Many of them are experienced and wise. They aren’t looking for publicity, except to attract donations – and often get those within a small circle, such as a church group, so don’t need wide publicity.
      But even they cannot help where an area is under tyranny.
      People are sending mower parts to Mongolia, where herders have problems with deep snow some years. (Their animals depend on being able to paw through snow to eat dry grass, but some years the snow is too deep. As they have horses the notion is to help them make horse-drawn mowers to stockpile “hay” near their winter settlement, though they also need a shelter over the hay. My memory is that their dwellings are somewhat better than those described herein for Tibetan herders, but that’s only relative.
      Efficient stoves were a technical topic on WUWT a couple of years or so ago, though the emphasis was climates warmer than Tibet, in ventilated environments.

  7. Tibet is noted for longevity so maybe those yak carbon particles are beneficial. Also, what about the high levels of carbon monoxide and carbon dioxide. Maybe we all need to adapt our bodies to thin air. Climb mountains.

  8. My new GMO yak’s dung doesn’t stink, nor does smoke when I burn it. It only emits CO2 and H2O.

  9. Some years ago, China distributed about 800,000 stoves equipped with chimneys in an attempt to reduce the mortality from biomass burning, which is experienced mainly by women and children. I’ve not heard whether the stoves were well accepted and could therefore help the situation in the long term.

  10. . .oh goodness, the only ‘response to this stupid study is ” No SH!T ! ” 🙂 🙂 ( . .sorry for the ‘swearing’ , mods; – I just couldn’t resist . . !)

  11. “Indoor air pollution is a huge human health problem throughout the developing world,” Saikawa says. “In a cold region like Tibet, the impact on individuals could be even greater…”

    But we don’t know, do we? And the study didn’t give us any way to tell. All it did was measure one form (i.e. particulate matter) of indoor air pollution and give some WHO estimates for global effects:

    Globally, the World Health Organization (WHO) estimated that 4.3 million people died prematurely in 2012 due to indoor air pollution from traditional stoves, fueled by coal, wood, dung or crop waste.

    This study is fairly useless without any associated health statistics. Is the measured “indoor air pollution” causing any problems for the study group? As far as we know the study group may not be living long enough for it to be a problem. They could easily be dying of other causes long before the “dangerous levels of fine particulate matter” have any effect.

  12. More than 50 years ago an entire virology laboratory was moved to Tibet to study the viral infectious organisms which were believed by leading infectious disease experts that was leading to the 50% infant mortality being observed. What was found, that the viruses infecting the infants were no different than those viruses found here in the lower 48.. What was further observed, that there was high indoor air pollution from burning Yak Dung in the traditional yurts with a central ceiling hole to let the smoke out.
    In Papua New Guinea, traditional women carry their infants on their backs go inside huts to cook traditional meals.
    In Southwest USA, Navajo Indians had lived and cooked in Hogans, structures constructed similar to the Tibetan Yurt with a hole in the ceiling to let the smoke out.
    These peoples and their traditional ways have exceedingly high infant mortality rates even in otherwise developed countries.
    What is missing from the measurements of particulates, which are indeed very high, are the other smoke compounds: known carcinogens, oils and tars, and the most potent in causing acute respiratory illness are the aldehydes, In the case of burning biofuels, acrolein, a short lived and highly reactive aldehyde damaging the respiratory systems’s host immune and defense system.
    The aldehydes play a significant role in the “sweet” smell of a woodburing fireplace or stove.
    The woodturning fad that swept North America after the First Oil Embargo by OPEC in the 1970,s helped introduce an element of science into studying the issues of biomass burning, science we are still living with today, repeating what had already been discovered..

    • I’ve tried a similar device in Nicaragua with some families there. They do burn more efficiently, but at the end of the day in “dirt floor poor” communities, accidents with indoor cooking and open fires kill or horribly maim so many children that smoke and particulate emissions are a secondary risk. I’m constantly working to convince them to take it all outside and out of reach of the kids. But that brings up another problem – these devices are valuable and easy to steal, whereas an open fire is not.

      • Iffen they built a few “coal fired” generators in Africa or Nicaragua …. then they could give those needy people those “cheapy” 2-burner electric “hotplates” … thus solving the other problems.

    • “More than a billion women still use open flames to cook for their families and to heat and light their homes. Accidents are commonplace. In developing countries, severe burns affect nearly seven million people a year – particularly low-income women and children – according to the World Health Organization’s Global Burden of Disease statistics.
      More women worldwide are severely burned each year than are diagnosed with HIV and TB combined. South Asia is at the epicenter of the burn crisis, where more children die from severe burns than from HIV/AIDS, malaria and respiratory disease combined. Burns are India’s third leading cause of burden of disease, with more than 3 million people burned each year. “

    • Great post Liz. It is a huge problem. Anyone who has been overseas must know how difficult those folks have it compared to those of us in the west. It used to take two washings of my clothes when I came back from overseas to get the smoke smell out. My high efficiency wood fireplace probably cost more than some of these people earn in a decade or two.

      • Jeff Kreiley
        I have the campstove model. Works great, no visible smoke and charges my cell phone as well.

        How does it generate the cell phone energy? Temperature differential doesn’t seem high enough to create enough (voltage x current) even for that.

    • that is a deluxe rocket stove, they can also be made from a couple tin cans, or stacking bricks in the right orientation
      lots of “how to build a rocket stove” videos out of very simple materials on youtube

  13. Sheez guys, at least this research focuses on:
    a.) non-catastrophic climate science
    b.) science to help the poor, especially fuel poverty conditions
    and
    c.) Their abstract indicates that

    BC and PM2.5 concentrations in a stone house using a chimney stove were 24.5 and 873 μg/m3, respectively.

    while the EPA PM2.5 is a 35 μg/m^3 (24-hour).
    Which implies that if they don’t see radical health problems differential between various types of homes
    then the EPA’s insane stance on some of these particulate levels will be in question as there will be data to reign them in.

  14. Actually studies on the effects of lampblack (carbon) show that it is not very harmfull.
    It is more likely that other emissions from the smoke are doing damage, perhaps carbon monoxide or tar

    • Stuart, it is mostly unburned aromatics contained in ‘soot’. Many of those are carcinogenic in animal models at high concentrations. But there are experimental threshhold effects, hence the second hand smoke controversy.

  15. “We want to use our data to make the world a better place,” Saikawa says. “The ultimate goal is to reduce pollution from biomass fuels in ways that benefit human health and reduce the climate impact.”
    ===============
    And you figured that a more efficient method of burning yak dung was the place to start ?
    Every little bit helps, but let’s broaden our horizons some ?

  16. As we’re surrounded by pastureland, I’m going out to forage for ‘cow pats’ first thing tomorrow for our log burner. Bet they don’t roar and spit nearly as much as our recent Christmas tree did – we thought it would explode. Never again. Live and learn, eh.

    • A lot of people newly introduced to fireplaces think they can burn their tree by rapidly stuffing it into the hearth as it is consumed. They cleverly stick the small end in first, knowing it has the least fire potential. The moment of learning comes when the entire tree is afire before they can get it in the fireplace. Christmas trees are about as dangerous as an equivalent weight of gasoline. Yak poo is much safer.

  17. The ultra greens would love to see the Tibetans not burn anything to heat their homes and just freeze to death. Why don’t the greenie heads stump up themselves for environment spoiling wind farms and solar panels so they can have clean electricity for their heating? Better still for the Greenies, get others to pay for it.The effect on global warming from burning Yak dung would have so many zeros after the decimal point that it would use half the ink on the planet to write. I will refrain from the obvious comment about this study-a load of…….

  18. The North American colonists had the same problem with the wood they used to stay warm in the Winter. Benjamin Franklin saved many American lives when he invented the Franklin stove in 1742, which by countercurrent heat exchange, heated homes more efficiently and exposed people to less smoke than the stoves it replaced. However, the American appetite for wood, for heat, industrial energy, and construction, left the Northeast USA almost bare of trees. Today, it is largely dense-second growth forest, due to fossil fuels replacing wood. I live on a street named for the view of the valley it commanded. Today, the forest is so thick, it is like driving through a tunnel, when the leaves are on the trees. There is no view whatsoever. Petroleum also replaced whale oil for light and industrial lubrication.
    People who know history know that fossil fuels are the best thing to ever happen to the environment, when compared with what they replaced.

    • Caveman,
      I came from the western slopes of the Appalachian Mountains in Pennsylvania and my grandfather and great grandfather helped in the removal of those trees – floated many down the local stream into a couple of different rivers and on to Pittsburgh. Often flat bottomed boats were built there and carried people on down the Ohio River.
      Many of the old places now have a newer house and are treed-in, as you say.

    • Caveman,

      …American appetite for wood, for heat, industrial energy, and construction, left the Northeast USA almost bare of trees.

      Don’t forget mining timbers and railroad ties. I think those two were responsible for more deforestation than all the others combined.

    • Quote: “People who know history know that fossil fuels are the best thing to ever happen to the environment, when compared with what they replaced.”
      Yes, you hit the nail on the head! Not only because the woods became the chance of recovery, but also because of the very valuable liberation of fossil carbon back into the cycle of life in form of atmospheric CO2.
      Just imagine, that we started with a lousy and therefore still plant stressing CO2 concentration of only 280 ppm before the industrial revolution ! Just 100 ppm more than the shockingly low 180 ppm we had at the end of the last ice age, when plant life on the continents came dangerously near to the brink of extinction (below 150 ppm).
      Thus, let’s be sensible and liberate as much carbon as possible. Join the carbon liberation brotherhood, the carbonist party, for the sake of Mother Gaia … 😉

    • And CavemanMD, don’t be forgettin about all of that CO2 that is still sequestered in all that “clear-cut” boards, beams and lumber that was used to build the Great Cities from the North central to the East coast of the US.

  19. Obama and his EPA need to get active on this world issue! They might consider a treaty that will prohibit this bad habit. Indeed let them suffer the global warming agenda and freeze to death as opposed to harming not only themselves but our planet! I am not sure about how to include the sarc notation or if it appropriate.

    • The EPA is already active in this through the Global Alliance for Clean Cookstoves which is an initiative of Hillary Clinton, through the United Nations Foundation (look it up before assuming what it is) in turn through the State Department (when she was Secretary).
      The EPA is represented on the ANSI team of 28 people participating in ISO Technical Committee 285 ‘Clean cookstoves and clean cooking solutions’. An EPA staffer is the ANSI team lead and casts the votes. They basically propose an All-American solution which for a few years was assumed to be improved biomass stoves. However that changed when it was revealed by Hillary in November that the long term plan is to move everyone to LPG and electricity and end all solid fuel combustion.
      The EPA under Bush and Obama supported their Partnership for Clean Indoor Air with two minor staffers and still maintain a legacy website.
      The EPA’s war on coal obviously extends to coal stoves needed in North Asia. Not sure what that will lead to as there is nothing else to burn in most places.
      I am in Ulaanbaatar at the moment and if you don’t burn coal and you are poor, you die. Quickly, not from air pollution.
      Improved combustion in domestic stoves has cleared the city air of about 50% of ambient PM2.5 in the past 3 years – through a stove replacement programme. I believe it is the first time, ever, that a city has substantially cleaned it’s air without changing the fuel. Much more can and is still being done.

  20. “Globally, the World Health Organization (WHO) estimated that 4.3 million people died prematurely in 2012 due to indoor air pollution from traditional stoves, fueled by coal, wood, dung or crop waste. In comparison, WHO estimated that outdoor air pollution was linked to 3.7 million deaths that year.”
    And the number that died prematurely or otherwise from breathing increased levels of ambient atmospheric carbon dioxide pollution…………………..Zero.
    And the increase in global temperature from the accelerating increase of CO2 over the past 15+ years………..slightly more than zero.
    More importantly:
    The estimated increase of value in crop yields/world food production from increasing CO2 over the last 50 years?
    That number also has some zero’s in it too……….. 12 to be exact. However, they come before the decimal point.
    $3,000,000,000,000+
    That would be over 3 trillion dollars.
    http://www.co2science.org/education/reports/co2benefits/MonetaryBenefitsofRisingCO2onGlobalFoodProduction.pdf
    What is the number that represents money spent for grants, research, taxes, technology, government programs and so on to study and address carbon dioxide pollution?
    That number also has at least 12 zeros to the left of the decimal point.
    So I guess increasing carbon dioxide is a break even game.
    The huge value of benefits bestowed by CO2 to society are almost completely offset by the huge cost to society from those using it to fund their anti CO2 endeavors.
    Ironic.
    This would be like winning a trillion dollars in the lottery and simultaneously, declaring that $100 bills are dangerous to handle and must be studied.
    Research includes:
    1. Measuring the amount of emissions from burning various sized piles of 100 dollar bills.
    2. Testing the buoyancy of $100 bills by dumping them into deep bodies of water and determining the length of time before they can no longer be detected on the surface.
    3. Measuring how many $100 bills it takes to wipe your ass and studying the pattern of them as they are flushed down the toilet.

    • I’ll see your $3 trillion and . . .
      I drove across the USA last summer to hang out around Yellowstone (and fish for wiggly water creatures) and I stopped and ate and visited in diners. Farmer told me he only harvested 12 or so bushels of soy beans/acre a couple of years ago, but this year has been 75-98 bushels/acre. Iowa was stunningly beautiful cropland, except for those stupid wind machines. Of course this was the warmest year in planetary history. Commented on N Y Times digest of devastations last 2 nights. One with simply a link to WUWT. Gonged both nights. Sorry for rambling, but the breadbasket was a stunner. I’d worked out there in my youth so had some basis for comp.

    • If the greens get their way, someday we’ll be using those $100 bills to light our yak dung fires.

  21. All you get from that lot is yak yak yak
    Okay, no chimney?
    Makes sense, you want all the heat.
    A further problem in a cold climate is humidity, just heat means very dry air. Ventilation with water recovery is not so easy.
    Not so long ago in the UK it was common to use oil heaters with no flue. Still fairly common with gas.

  22. At the risk of belabouring matters. Say you had 300 Liberty ship Nuclear Plants. They could have done WONDERS around the world. Say one (or two or three) of them has a “problem”. Well, you tow it out to the deep ocean and SINK IT…as the Thresher and the Scorpion. Both found, both with minimal detected leakage from the reactor. RIP Thresher and Scorpion! But the net gain in helping around the world, invaluable.

  23. All in all, a very good argument for expanded use of natural gas. Let thousands of years of natural processes refine the organic matter before you burn it.

  24. Seriously?? They were paid for this?? Someone (taxpayers I’ll bet) wasted a bundle on such obvious drivel. Geesh!

  25. Thus the importance of publicizing “The Moral Case For Fossil Fuels”.

    You’ve heard that our addiction to fossil fuels is destroying our planet and our lives. Yet by every measure of human well-being life has been getting better and better. This book explains why humanity’s use of fossil fuels is actually a healthy, moral choice.

  26. Rather than state the obvious, Bjorn Lomborg offers solutions:
    Better stoves can reduce indoor pollution

    According to a new study for the Copenhagen Consensus, the simplest solution is to replace inefficient, smoky stoves by more efficient, less smoky ones. Providing 1.4 billion people with such improved stoves would save almost 450,000 lives a year and avoid almost 2.5 billion days of illness annually.
    Moreover, more efficient stoves would on average save about 30 percent fuel, which translates into a savings of up to $57 per household per year, and at the same time make cooking more efficient and less time consuming. In total, the health and non-health benefits are estimated at $52 billion per year. . .
    So for every dollar spent on better stoves would do $10 worth of good. This gives us an excellent opportunity to compare this target for air pollution with all the other worthy targets proposed for the next 15 years..

    • Thanks for that, SOB!
      Found this web site ‘interesting’. A little bit on the ‘old hippie’ side, but interesting low tech designs for max heat extraction and retention! This may be a viable heater for my detached garage… and a ‘safe’ place to try out a bit more engineered design. The videos waaaaay down the site are more informative about designs and building…..
      Mac
      http://www.richsoil.com/rocket-stove-mass-heater.jsp

  27. As I watch through the glass doors of my wood-burning stove the great quantity of thermal energy returning to space, I enjoy the toasty warmth that fills my house.
    Any recrimination about the inefficiency of the stove is overwhelmed by the knowledge of how the entire planet is squandering the energy it is receiving on an on-going basis, spitting back everything it receives like there’s no tomorrow.
    It is interesting that the Dené people of NW North America didn’t figure out pottery, metals or wheels but they had pretty good chimney systems in all their habitations. Meanwhile people in warmer climes still squint through the haze in their convection-impaired dwellings.

    • Luckily all the energy that there ever was in this universe is and always will be, it just has a thing about staying in the same place for very long.

  28. You could probably sell that stuff by the gram in Boulder Seattle, and they would indeed smoke it, thinking somehow it was a good natural high.

  29. “Globally, the World Health Organization (WHO) estimated that 4.3 million people died prematurely in 2012 due to indoor air pollution from traditional stoves, fueled by coal, wood, dung or crop waste.”

    We’ll since the IPCC is concerned with all global issues concerning energy from fossil fuels to cow dung, they will immediately put a carbon tax on dung and crop waste in addition to coal.

  30. Isn’t this why we tried to start electrifying villages in Africa with solar panels in the late 80’s?
    Yes it is, Other prjindigo, yes it is…

  31. Burning yak dung can be done very cleanly by creating the combustion conditions that provide adequate preheating of the primary air supply and enough flame space above the fuel to complete the breakdown of the longest molecules.
    This was demonstrated by a team of Engineers Without Borders from Colorade State Univ in Tibet a few years ago who burned yak dung at elevations above 13,000 ft. They were investigating the performance of a semi-gasifier at high altitude. They reported that it burned very well. Semi-gasifiers can be refuelled while gasifiers typically are ‘batch stoves’.
    The problem is not burning yak dung, it is NOT burning it completely. This is not a mystery. Dung is a very good fuel. Prakti Design in India also has a novel stove specifically designed to burn dung well.
    Chimney stoves are a very effective and semi-permanent method of dramatically improving indoor air quality. This has been known for centuries.
    The number of ‘deaths’ from indoor air is surprising. I believe the correct metric is not ‘deaths’ but ADALYs or DALYs which is a measurement of ‘life years’ not deaths. The reference would be the WHO’s 12 November 2014 publication. The claimed number of DALYs has been approximately doubled every 18 months which is itself curious as the number of people burning biofuels remains approximately constant.
    Looking into the documents cited by the WHO one finds there is no new data. There are citations of still other documents. In those source documents one finds far more uncertainty than is presented by the WHO. The number is ‘0-4.2 million DALYs’ not ‘4.2’ and not ‘deaths’. So am I misinterpreting the sources? The roots? Maybe, maybe not. Let each read and see. Perhaps my eyes deceive me. What ever the number is, it is quite a leap to take ‘0-4.2m’ and turn it into 4.2m at the stroke of a delete key.
    Similarly, looking into the root citations of the estimated influence of poor air quality outdoor air one finds 0-2.2m and 0-1.5m and so on. This is a very uncertain field where the numbers seem to have a life of their own.
    One of the most curious numbers is that of the claimed required decrease in exposure needed to create a significant, measurable decrease in disease attributable to PM2.5. It is frequently claimed that a reduction of 90% or more is needed to get a solid positive health response. That is for decreases. For increases, however, the effects are claimed to be linear. Thus increasing PM2.5 by 100% has immediate and measurable deleterious effects, but reducing it again by half to the original level creates no measurable reduction. That is illogical. They can’t have it both ways.
    Exposure to PM2.5 (particles with an aerodynamic diameter of less than 2.5 microns) at a low level has no detectable effect. We deal with it. Above this limit, health effects can be detected, and the effects are assumed to increase as the dose increases. That makes sense. Translating that into ‘deaths’ is a dark art, however. That is why there are such huge ranges in the estimates. I don’t think anyone is brave enough to claim that 4.2 million people died from the effects of poor indoor air quality in a journal article.
    In order to address this issue internationally Hillary Clinton announced in New York her plan (the event was 20-21 Nov 2014) through the GACC, to eliminate the burning of solid fuels by promoting LPG and electricity for all the poor in the world. It was an interesting coincidence that the WHO announcement of a large increase in the number of DALYs (interpreted as deaths) was announced the week before. Much was made of it.
    I would like stove science and indoor air quality to be driven by validated models and sound protocols that provide clear guidance as to what the problem is and what the risk/benefit/cost ratios of various interventions are.
    The users of yak dung (which is a very convenient and free fuel) is going to continue for a long time throughout Asia’s grazing lands. The correct interventions are the humble chimney and off the shelf advanced combustion technologies applied in culturally acceptable ways to their cooking and heating needs.

    • Having had some experience of the use of lpg in developing countries, I would suggest that the Tibetans are a damn sight safer burning yak dung.
      Why is it that some people in the ‘developed’ West insist on interfering with the ways of life of others??
      We will all die of something………….. in the case of the lucky Tibetans they have little to fear from traffic accidents.
      However, I am unsure of the figures relating to injury or death from assault by randy yaks

      • Actually Yaks are pretty dangerous. A neighbour of mine had his prize stallion gored to death by his long time pasture mate, a bull Yak. No bull. 😉 Probably made a bad pun, Yakkity Yak.

  32. They ought to have started a study on all those folks smoking legalized shit in Colorado and Oregon.

  33. This study is another hint to the rather obvious fact that cold kills far more people than heat. This time not just the cold alone but also the indoor air pollution produced by the need of fighting the cold to survive at all…

  34. What does a non tea-drinker do when presented with a plethora of tea varieties at xmas ?
    Accept them with a smile ?
    The Boston harbor thing has already been done to death.
    So, where does that leave you ?

    • What does a non tea-drinker do when presented with a plethora of tea varieties at xmas ?
      Same thing a carnivore does when presented with a ‘tofu burger’: Politely decline. And ask them to ’embrace diversity’…. by offering a good cup of coffee, with decent splash of scotch in it! Then brew them a proper cup of ‘Irish coffee’ and settle in for a fine and detailed conversation.

  35. ‘WHO estimated that outdoor air pollution was linked to 3.7 million deaths that year’ I wonder how they came u with that estimate. Could it have been 0n a computer?.

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