Sadly, the paper it is based on seems to be behind a pay wall; but indeed, it seems to be about the properties of the properties of wood smoke and the potential problems it could cause—rather than an investigation into actual health consequences.
So, until further notice, I’m filing this story under “Cocktail party factoids”...
EDIT: actually, it seems the paper mentioned is available online—see RichardKennaway’s comment. I’m reading it now—and notice the acute danger of confirmation bias to somehow not contradict my pre-EDIT comment… In short it seems there is indeed a real danger coming from wood smoke, however the examples all seem to be from bush fires etc., and the gasses that fireplaces put in the atmosphere, less so from people looking at a fireplace (but obviously inhaling the smoke won’t do you much good).
Abstracting this a bit, I did not have the non-rational reactions that Harris predicted; instead (like many people here), my first reaction was skepticism. After reading the paper, I’m a bit less skeptical. But I’d still like to know specifically about the health effects of using a fireplace in one’s house.
I can attest to the main point of the article: the irrational ire that this issue invokes in people. This letter to the editor is in no way unique in my neck of the woods. Though that can also come from it being a highly religious, republican/libertarian sort of place. Amongst my friends, there is much less of this rage Harris speaks of. We readily admit the down sides, but up here, a blackout of sufficient duration (a couple hours, maybe?) could be lethal, and would certainly cost thousands of dollars in damage if water pipes freeze up.
Harris did seem to commit one of the gravest wikipedian sins: citation needed.
Here’s a little more info, for your edification.
The EPA talks about health effects stemming from Carbon Monoxide, Nitrogen Dioxide, structural damage resulting from particles abrading soft tissues, and cancer from deposited carcinogens that hitchhike on the small particles. One of the sources cited in that list is Zelikoff’s The Toxicology Of Inhaled Woodsmoke in the Journal of Toxicology, which I think is a good place to start.
There’s also some downloadable articles on this site which might be of use as gateways to more info.
Edit: It occurs to me that since I’m enjoying reading the Zelikoff article that I should summarize some interesting points.
-The WHO estimates that indoor air pollution (no clue if there were other major sources beyond wood and dung burning) accounts for 2.2 to 2.5 million annual deaths around the world.
-Biomass fuel is not terribly good in terms of combustion efficiency, which is why they produce so much crap.
-Emissions include -aldehydes, hydrocarbons, CO, NO_x and SO_x, volatile organics, chlorinated dioxins, and free radicals.
-Cooking smoke increases risk of chronic obstructive lung disease, respiratory infections, and in children pulmonary tuberculosis.
-Most woodburning in the United States is done by middle to upper-middle income, and use has risen dramatically since the 1980s.
-Temperature inversions trap these particles, which is bad for places like British Columbia (and incidentally my town)
-Upwards of 70% of outdoor woodsmoke reenters the house and neighboring houses (that is sourced to Pierson et al. 1989).
-Fireplaces are about as bad as non-airtight stoves, but worse than airtight ones. Except that airtight ones have less oxygen, which apparently facilitates making more exotic organic chemicals.
-Now it starts talking specifics. CO levels in woodstove homes have been shown to make carboxyhemoglobin and increases angina in people with cardiac disease. Nitrogen oxides bind to hemoglobin to produce methemoglobin and hematologic aberrations, which messes up enzyme systems, injure vascular membranes, which leads to edema and bronchoconstriction in asthmatics. The hydrocarbons are immunosuppresants and obviously carcinogenic (both are known in animals and suspected in humans). Formaldehyde and acrolein are the primary aldehydes, and they are associated with upper airway irritation, headaches, exacerbating bronchial asthma, and cancer.
-One of the most interesting thing about scientists is they can talk about horrible things like this, and start a paragraph with “One of the most interesting components of woodsmoke pollution is PM” (Particulate matter).
-Short-term exposure to particles is linked with a lot of bad shit. Including death and reduced recovery rates from infectious diseases.
-They’ve done animal studies and found direct links between woodsmoke and scary sounding names like necrotizing tracheobronchial epithelial cell injury, lung cancer, decreased ventilatory frequency and response to CO2.
-Adults with prolonged exposure get: chronic bronchitis, chronic interstitial pneumonitis and fibrosis, cor pulmodale, interstitial lung disease, pulmonary arterial hypertension, and altered pulmonary immune defense mechanisms.
-Children have it worse: decreased pulmonary lung function in asthmatics, increased rates of acute bronchitis (increased severity and frequency of wheezing and coughing), increased incidence, duration and severity of acute respiratory infections.
Then there’s immune system issues, which are of a persistent and progressive nature. They talk about some rat studies and how particles <2.5 microns made pneumonia worse. Most of this section went right over my head.
-”While the mechanisms by which woodsmoke may have acted to persistently suppress bacterial clearance are not yet clear, results from this part of the study demonstrated that short-term repeated inhalation of woodsmoke [...] compromised pulmonary host resistance against an infection, pneumonia-producing lung pathogen well after exposure ceased.”
-This study displayed that recovery rates were lessened in woodsmoke-exposed rodents in a time-dependent manner. A different study showed that decreased immune system starts about 4 days from exposure (not sure the exposure regimen) and lasted up to 25 days with repeated exposure. That study also showed that it was because particles release formaldehyde slowly over the course of being in the body, which is how it is a continuous progressive effect.
I always hate reading abstracts before reading an interesting paper. It should say Spoiler Alert, not Abstract… Also, I really like how a paper with good citations is several pages shorter than the size of the document. Hitting Summary before expected always gives me a slight endorphin rush.
Sadly, the paper it is based on seems to be behind a pay wall; but indeed, it seems to be about the properties of the properties of wood smoke and the potential problems it could cause—rather than an investigation into actual health consequences.
So, until further notice, I’m filing this story under “Cocktail party factoids”...
EDIT: actually, it seems the paper mentioned is available online—see RichardKennaway’s comment. I’m reading it now—and notice the acute danger of confirmation bias to somehow not contradict my pre-EDIT comment… In short it seems there is indeed a real danger coming from wood smoke, however the examples all seem to be from bush fires etc., and the gasses that fireplaces put in the atmosphere, less so from people looking at a fireplace (but obviously inhaling the smoke won’t do you much good).
Abstracting this a bit, I did not have the non-rational reactions that Harris predicted; instead (like many people here), my first reaction was skepticism. After reading the paper, I’m a bit less skeptical. But I’d still like to know specifically about the health effects of using a fireplace in one’s house.
I can attest to the main point of the article: the irrational ire that this issue invokes in people. This letter to the editor is in no way unique in my neck of the woods. Though that can also come from it being a highly religious, republican/libertarian sort of place. Amongst my friends, there is much less of this rage Harris speaks of. We readily admit the down sides, but up here, a blackout of sufficient duration (a couple hours, maybe?) could be lethal, and would certainly cost thousands of dollars in damage if water pipes freeze up.
Harris did seem to commit one of the gravest wikipedian sins: citation needed. Here’s a little more info, for your edification.
A copy of Harris’ cited source that isn’t paywalled.
The EPA talks about health effects stemming from Carbon Monoxide, Nitrogen Dioxide, structural damage resulting from particles abrading soft tissues, and cancer from deposited carcinogens that hitchhike on the small particles. One of the sources cited in that list is Zelikoff’s The Toxicology Of Inhaled Woodsmoke in the Journal of Toxicology, which I think is a good place to start. There’s also some downloadable articles on this site which might be of use as gateways to more info.
Edit: It occurs to me that since I’m enjoying reading the Zelikoff article that I should summarize some interesting points. -The WHO estimates that indoor air pollution (no clue if there were other major sources beyond wood and dung burning) accounts for 2.2 to 2.5 million annual deaths around the world. -Biomass fuel is not terribly good in terms of combustion efficiency, which is why they produce so much crap. -Emissions include -aldehydes, hydrocarbons, CO, NO_x and SO_x, volatile organics, chlorinated dioxins, and free radicals. -Cooking smoke increases risk of chronic obstructive lung disease, respiratory infections, and in children pulmonary tuberculosis. -Most woodburning in the United States is done by middle to upper-middle income, and use has risen dramatically since the 1980s. -Temperature inversions trap these particles, which is bad for places like British Columbia (and incidentally my town) -Upwards of 70% of outdoor woodsmoke reenters the house and neighboring houses (that is sourced to Pierson et al. 1989). -Fireplaces are about as bad as non-airtight stoves, but worse than airtight ones. Except that airtight ones have less oxygen, which apparently facilitates making more exotic organic chemicals.
-Now it starts talking specifics. CO levels in woodstove homes have been shown to make carboxyhemoglobin and increases angina in people with cardiac disease. Nitrogen oxides bind to hemoglobin to produce methemoglobin and hematologic aberrations, which messes up enzyme systems, injure vascular membranes, which leads to edema and bronchoconstriction in asthmatics. The hydrocarbons are immunosuppresants and obviously carcinogenic (both are known in animals and suspected in humans). Formaldehyde and acrolein are the primary aldehydes, and they are associated with upper airway irritation, headaches, exacerbating bronchial asthma, and cancer. -One of the most interesting thing about scientists is they can talk about horrible things like this, and start a paragraph with “One of the most interesting components of woodsmoke pollution is PM” (Particulate matter). -Short-term exposure to particles is linked with a lot of bad shit. Including death and reduced recovery rates from infectious diseases. -They’ve done animal studies and found direct links between woodsmoke and scary sounding names like necrotizing tracheobronchial epithelial cell injury, lung cancer, decreased ventilatory frequency and response to CO2. -Adults with prolonged exposure get: chronic bronchitis, chronic interstitial pneumonitis and fibrosis, cor pulmodale, interstitial lung disease, pulmonary arterial hypertension, and altered pulmonary immune defense mechanisms. -Children have it worse: decreased pulmonary lung function in asthmatics, increased rates of acute bronchitis (increased severity and frequency of wheezing and coughing), increased incidence, duration and severity of acute respiratory infections.
Then there’s immune system issues, which are of a persistent and progressive nature. They talk about some rat studies and how particles <2.5 microns made pneumonia worse. Most of this section went right over my head. -”While the mechanisms by which woodsmoke may have acted to persistently suppress bacterial clearance are not yet clear, results from this part of the study demonstrated that short-term repeated inhalation of woodsmoke [...] compromised pulmonary host resistance against an infection, pneumonia-producing lung pathogen well after exposure ceased.” -This study displayed that recovery rates were lessened in woodsmoke-exposed rodents in a time-dependent manner. A different study showed that decreased immune system starts about 4 days from exposure (not sure the exposure regimen) and lasted up to 25 days with repeated exposure. That study also showed that it was because particles release formaldehyde slowly over the course of being in the body, which is how it is a continuous progressive effect.
I always hate reading abstracts before reading an interesting paper. It should say Spoiler Alert, not Abstract… Also, I really like how a paper with good citations is several pages shorter than the size of the document. Hitting Summary before expected always gives me a slight endorphin rush.