[Stoves] Air pollution kills

Xavier Brandao xav.brandao at gmail.com
Fri May 11 16:31:12 CDT 2018


Dear Crispin,

 

OK, but maybe not all studies are like the Korean one.

Then, for Ulan-Bator, for Mongolia, and as well for the world, there is a
need of a serious meta-analysis, which also reviews and criticizes the
methodology of the epidemiological studies on air pollution.

 

Then only, we might have a better view on the current landscape of research,
of the state-of-the-art on air pollution and health.

 

« There is correlation between OAP and IAP and infections, but they are
associations, not causal relationships.”

Sure, I understand the difference. But from what I understand there are
fields of research where this is the best you can get. That doesn’t mean it
doesn’t have grounds.

I wouldn’t throw epidemiology with the bath water. It seems to me that it is
epidemiology which found the link between smoking and lung cancer:

https://www.theguardian.com/society/2005/apr/24/smoking.medicineandhealth 

 

“The claim that 4.3m people ‘die from air pollution’ per annum is clearly
false”

Indeed, but they might say instead: “Based on our data and statistics and
methodology, we have attributed the death of around 4.3 million people to
air pollution. It might be less, or more. We might be wrong, but this is the
best we have, sorry. The fact is that we highly suspect air pollution to be
dangerous for human health, so beware.”

That would be more correct. Would that change the outcome, which is to take
public policy measures to try to mitigate air pollution?

 

« Who simple is this statement? Did anyone measure IAP in the rural areas
where they burn dung for heating and cooking? Many people in the rural areas
are reasonably well fed and clothed. A lot of people in Ulaanbaatar were
driven there by absolute poverty and live in desperate conditions, some
depending on coal vouchers to obtain fuel. How did the temperature of the
home affect the incidence, and what is the socioeconomic conditions of the
families with high occurrence? Are there bronchitis epidemics in town that
do not occur in rural areas because the possibility of transmission is so
much lower? Yes the OAP is much lower in rural areas, but is their exposure
to smoke, for example, lower or higher?”

Sure, it raises a lot of questions. But let’s say we believe the data the
doctors have. I’d say this is a fact:

”Children in Ulaanbaatar, are taken bronchitis in 1.4-2.7 times and
bronchitis asthma in 5.5-7.9 times more than children who are living in
rural areas”

Mentioning this “less air pollution.” is already attributing a cause. 

 

“Prof Lodoysamba confirmed the ‘colder’ hypothesis this winter using a
pretty sophisticated monitoring station at his home in Nalaikh with
thermometers at different heights above the ground.”

Maybe the cold is responsible of the bronchitis in Nalaikh, but not in Ulan
Bator. Maybe the cold is responsible everywhere and that is not well
measured or known.

Then, that “colder hypothesis” would infirm what was found in this study,
that air pollution from stoves was the main cause. Prof. Lodoysamba was one
of the co-writers of this study:

http://www.urbanemissions.info/wp-content/uploads/docs/2013-09-AQAH-Ulaanbaa
tar-PM-Pollution.pdf 

 

“Attributing something as a cause does not mean that removing the attributed
cause avoids the problem. Suppose the attribution was in error by 80%?”

Sure, it could well be that: “oh, every household has an electric stove now,
but still the number of bronchitis cases are high.”

Science is never definitive, always evolving.

 

“Regarding proximity to highways: who lives next to noisy and polluted
highways in California: the well fed and exercised with good medical
treatment? Or poor people with poor health coverage, bad diets and no access
to recreational facilities?  Correlation is not  causation. “

We’d need to look at the study methodology to know if they took this factor
into account. Maybe they did. Maybe they compared poor people next to
highways, to poor people remote from highways.

 

“There must be children for whom it is the worst environmental risk, and
others for whom it is now.”

Sure, but if there are 10 000 children in the first group and 2000 in the
second group, then air pollution is the biggest environmental risk for
children in UB.

 

“The major impediment to achieving this is the parade of baseless claims
that coal cannot be burned cleanly”

Sure, if coal stoves can burn cleanly like or almost like electric stoves,
that’s fine by me.

 

“That is unbelievable. The “main source”? The cause? That is a clear claim
that second hand smoke causes bronchitis.”

Well, cause, by association. Actually, it doesn’t necessarily makes a
hierarchy between causes, it also says: “Second, other potential risk
factors of LRTI-related hospital admissions might have been overlooked in
our investigation, such as the type of fuel used in household stoves,
nutrition, antenatal cigarette smoke exposure, and nursery attendance, where
children might contract an infection from others.Therefore, caution should
be taken in interpreting these study findings.“

 

”Think about that. The record low for Ulaanbaatar is -54 C (2002). The
annual average is -2C. Is it possible that people earning $2500 per year
live in a chronically underheated home? Ya think??”

If millions of dollars should go to preventing under-heating rather than
clean stoves, then that is worth a medical study, to attribute deaths to
cold. If there is no such study, it is understandable public deciders well,
decide, to focus on air pollution.

It seems to me that the good news is that solving the issue of cold in homes
and IAP go hand-in-hand.

 

”Some say 45% depending on where you measure it. It was improved uuugely.
Yet people popped up to say nothing was achieved by the programme. Short
memories.”

For sure, celebrating successes and giving credit where credit is due is
really important. Otherwise we tend to think we live in a bleak world where
nothing happens.

 

”I am sure asthma attacks decreased because air pollution aggravates asthma.
I do not have stats, however. It just seems likely.”

It seems to me also. And until you have a cohort of doctors, statisticians,
scientists to make more studies with a large number of variables, and check,
this is the best a public decider can get.

 

”Now we need to address the low pressure boilers which are more and more
common and burn 4 times as much fuel as the ger stoves, at least. They were
not included in the ger stove programme. We are working on the at the
moment.”

That seems exciting! Good luck with that.


Best,


Xavier

 

 

 

De : Stoves [mailto:stoves-bounces at lists.bioenergylists.org] De la part de
Crispin Pemberton-Pigott
Envoyé : mercredi 9 mai 2018 00:20
À : Discussion of biomass cooking stoves
Objet : Re: [Stoves] Air pollution kills

 

Dear Xavier

 

Thank you for being skeptical. Science works on challenges, nullis in verba.

 

On the IAP matter in UB, there are generalisations one can make and specific
circumstances worth noting. There is a study of the effect on indoor air
pollution from the improved stoves (Korean study, available in English). The
concluded that the improved stoves which reduce PM2.5 output by 90-98%
increased indoor air pollution, which was so unbelievable that I bothered to
investigate the study quite carefully.

 

What I found was that they did indeed measure an increase, on average, in
IAP but: the difference was well inside their margin of error (a small
fraction of the variations measured, rendering the conclusion meaningless.
Further, on those days when they were measuring, the ambient (outdoor) air
pollution closely matched the claimed indoor air quality, save that in every
case the IAP was lower than the OAP.  In short, all the Koreans measured was
the effect on IAP from outside air.

 

The worst aspect of the paper was that they claimed a statistically
significant difference: the new stoves provided worse IAP than the old
stoves – which the numbers did not support at all. There was a difference in
the averages, and the new stove measurements were higher, but the difference
was a small fraction of the Sigma 1 of their numbers, which is to say, the
difference was not statistically significant. 

 

Decent chimney stoves with a correctly fitted chimney have very little
effect on IAP. We have ample recent evidence of this in Kyrgyzstan if there
was any doubt. Improper operation can lead to fugitive emissions from the
stove – for example leaving the ash drawer open a bit ‘to give more power’
breaks the draft from the chimney and the top surfaces can leak smoke into
the room as they are no longer under negative pressure.

 

There is correlation between OAP and IAP and infections, but they are
associations, not causal relationships. We can ask Nikhil about which words
to use exactly. The claim that 4.3m people ‘die from air pollution’ per
annum is clearly false and a misrepresentation of the published evidence
used to support the claims that air pollution shortens lives – by
attribution (not medical evidence).

 

« Children in Ulaanbaatar, are taken bronchitis in 1.4-2.7 times and
bronchitis asthma in 5.5-7.9 times more than children who are living in
rural areas of less air pollution. » says Social Health institute.
http://www.unoosa.org/documents/pdf/psa/activities/2006/graz/presentations/0
102.pdf p 12.

 

Who simple is this statement? Did anyone measure IAP in the rural areas
where they burn dung for heating and cooking? Many people in the rural areas
are reasonably well fed and clothed. A lot of people in Ulaanbaatar were
driven there by absolute poverty and live in desperate conditions, some
depending on coal vouchers to obtain fuel. How did the temperature of the
home affect the incidence, and what is the socioeconomic conditions of the
families with high occurrence? Are there bronchitis epidemics in town that
do not occur in rural areas because the possibility of transmission is so
much lower? Yes the OAP is much lower in rural areas, but is their exposure
to smoke, for example, lower or higher?

 

When the Kyrgyz villagers were keeping their homes free of IAP (with
chimneys and non-leaking stoves) and 5 degrees warmer the incidence of
bronchitis dropped to zero (51 homes, 2016-17 season). I interviewed parents
in February in the Naryn region and they all said before they got the new
stove the children were “sick all winter” before and “much sicker than this
winter” and so on. Chronic cold spreads disease among children. Bronchitis
is a bacterial infection. PM2.5 is sterilized. So you are looking for
pre-dispositions caused by PM2.5, not ‘causes’. 

 

It is dusty pretty much everywhere. The city is definitely smokier, and it
can be quite bad if the wind drops, because below -30 the city is colder
than the mountains around, or communities at higher elevation such as nearby
Nalaikh where the coal comes from.  Prof Lodoysamba confirmed the ‘colder’
hypothesis this winter using a pretty sophisticated monitoring station at
his home in Nalaikh with thermometers at different heights above the ground.
The city, below -30, is colder, smokier, has a poorer diet and more fugitive
dust than rural areas. But a traditional stove burning dung can be pretty
smoky, and we have zero measurement of IAP in rural homes.

 

«So we concluded that the level of urban air pollution in the capital city
is clearly having an adverse impact on the pulmonary health of urban
Mongolian children.»

 

They can conclude that but that is no proof. That is an association. It is
why Nikhil keeps pointing out that you cannot make claims for causes and
avoidances without knowing a heck of a lot about the sub-population you are
examining.  Attributing something as a cause does not mean that removing the
attributed cause avoids the problem. Suppose the attribution was in error by
80%?

 

Regarding proximity to highways: who lives next to noisy and polluted
highways in California: the well fed and exercised with good medical
treatment? Or poor people with poor health coverage, bad diets and no access
to recreational facilities?  Correlation is not  causation. 

 

“UNICEF says: « Outdoor air pollution is the most significant environmental
risk faced by children in Ulaanbaatar.”

 

Hmm
  Is alcohol an environmental risk? What about smoking?  The air
pollution is awful on some days, and visible, and variable from place to
place. There must be children for whom it is the worst environmental risk,
and others for whom it is now. The point is that we can remove virtually all
of it with improved combustion of the very same fuels they now use. The
major impediment to achieving this is the parade of baseless claims that
coal cannot be burned cleanly, and therefore they must ban it – the only
fuel available at a price they can afford. The sheer stupidity of blaming
the fuel for the performance of the stove cannot have a greater effect on
the people. Those advocates of fuel bans based on the misbelief that the
fuel is the problem, are partnering with the advocates of ‘alternatives’
costing multiple times as much and which provide no additional benefit save
in some cases, convenience. Free electricity is lovely – if the nation can
afford it. No nation I know of can, so how can Mongolia?  Other countries
are now depending on the great progress made in coal stove designs from
Mongolia. How is it possible that the Mongolians are deprived of the
benefits of this work? Advocates, that’s how. Advocators of heat pumps,
subsidised electricity, dimethyl ether, natural gas, LPG, wood pellets,
processed coal – every and anything that costs a lot, but not
ultra-clean-burning coal stoves developed right up the road in a
university-owned, government-supported stove development centre!

 

“For bronchitis, this study points to indoor smoking from parents as the
main source of children’s bronchitis cases:”

 

That is unbelievable. The “main source”? The cause? That is a clear claim
that second hand smoke causes bronchitis.

 

“I didn’t see anywhere that respiratory diseases were due to the cold in
Mongolia.”

 

Think about that. The record low for Ulaanbaatar is -54 C (2002). The annual
average is -2C. Is it possible that people earning $2500 per year live in a
chronically underheated home? Ya think??

 

« With 50 % of the ambient PM pollution (and more in the winter months)
originating from household stoves for cooking and heating, this sector tops
the list of the most opportunistic of the interventions for better air
quality. »

 

That is 2013. Times have changed. The stove programme was in full swing in
2013. The % dropped from 88% (2010) in one district to an average of 45% in
2015 (in winter).  In summer the air is very clean (12 µg/m3, for example).

 

So, if « 7 million deaths » from WHO may be far fetched, it seems reasonable
to me to call for cleaner stoves.

And, in the case of Ulan Bator, to sensitize people against indoor smoking:
is it actually being done?

 

Preaching against smoking is everywhere. The number f people smoking in
developing countries is increasing rapidly because they are targeted by
vendors. The advertising has been driven out of developed country media. It
is very reasonable to call for clean stoves. Very clean. Why not? The
benefits are huge, but it is not the entire problem. Without doubt the
strangest country I have worked in is Mongolia because the clean burning
solutions were developed there, tested there, supported financially yet are
maligned for political purposes. Everyone wants to blame others for “not
solving the air pollution problem”. After the stove replacement programme
stopped at the end of 2015, air pollution was down 65%. Some say 45%
depending on where you measure it. It was improved uuugely. Yet people
popped up to say nothing was achieved by the programme. Short memories. 

 

I am sure asthma attacks decreased because air pollution aggravates asthma.
I do not have stats, however. It just seems likely. Now we need to address
the low pressure boilers which are more and more common and burn 4 times as
much fuel as the ger stoves, at least. They were not included in the ger
stove programme. We are working on the at the moment.  Products were tested
last week – efficiency was too high. I will reduce it.

 

In the meantime, Kyrgyzstan starts rolling out improved stoves (locally
made) to 14,000 homes, slowly at first. The coal combustors are all based on
the Mongolian developments. South Africa localised the design and we have a
model ready for testing since last Monday. It is a beauty, and will
incorporate lessons learned from the use of the plastic refractory materials
in Ulaanbaatar last year. It is a game-changer.

 

Keep pushing! Rocks don’t move by themselves.

Crispin

 



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