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Again, thanks to Kirk for some VERY interesting inputs of
expert-comments and data that I and many other Stovers do not
sufficiently appreciate. His attachment gives valuable ammunition
for the fight against Household Air Pollution (HAP)<br>
<div class="moz-forward-container"><br>
A quote from the linked report by CNN:<br>
<blockquote type="cite">In the poorer regions, such as South Asia
and most of Sub-Saharan Africa, where cooking with solid fuels
is common, household air pollution is the most important single
risk factor for women and girls.</blockquote>
<br>
Kirk wrote:
<blockquote type="cite">Yes, at least a reliable 95% reduction in
emissions over open fires, which actually are not well
characterized. </blockquote>
PSA: And if open fires are not well characterized (partly
because there are so many different configurations and fuels), our
baseline data is also rather "loose". And our own understanding
(by experienced Stovers who design and make stoves) is also with
problems because so much of stove production is really of stoves
that contribute little to the HEALTH solutions (but do reduce
forest destruction). Too many are merely Tier 1 or Tier 2 for PM
and CO emissions. But that is "techy-talk."<br>
<br>
I am trying to get to a better "visualization" (or written
expression) of HAP amounts that are sufficiently low to make a
major difference. <br>
<br>
Kirk concluded with "Stay tuned." so I await his reply to my
comment that I repeat here:<br>
<blockquote type="cite">Another way of saying the same thing:
When the current technology /equipment for testing stove
emissions is in use (such as for 75 minutes, which is 30 minutes
to boil plus 45 minutes for simmer), what would be the
equivalent of passive smoke from how many cigarettes that would
equal the Tier 0, 1, 2, 3, and Tier 4 levels? Think of this as
one person smoking (exhaling smoke) under the hood of the
equipment.
[Added: or into a small kitchen-size area.]<br>
<br>
I think that these comparisons can be useful, but only when we
have some numbers will we be able to see if the info is useful.
</blockquote>
<br>
I hope that someone is forwarding these messages to people
(medical types, etc.) who are not subscribed to the Stoves
Listserv. I have been assured in the past that leadership in the
GACC does monitor the Stoves List messages. But I am not sure
that other groups such as ACESS and regional groups do monitor and
do forward useful messages to their contacts.<br>
<br>
PLUG: This summer at Stove Camp at Aprovecho (22 - 26 July) we
will be measuring emissions for different comparisons about
emissions (same equipment, but not just WBT data). As one of the
main presenters and organizers of the activities, I hope that many
of you will consider attending. <br>
<br>
Paul (and be sure to read the attached document)<br>
<br>
<pre class="moz-signature" cols="72">Paul S. Anderson, PhD aka "Dr TLUD"
Email: <a class="moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a> Skype: paultlud Phone: +1-309-452-7072
Website: <a class="moz-txt-link-abbreviated" href="http://www.drtlud.com">www.drtlud.com</a></pre>
<br>
<br>
-------- Original Message --------
<table class="moz-email-headers-table" border="0" cellpadding="0"
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<th nowrap="nowrap" valign="BASELINE" align="RIGHT">Subject:
</th>
<td>Re: Between PM 2.5 and PM 10</td>
</tr>
<tr>
<th nowrap="nowrap" valign="BASELINE" align="RIGHT">Date: </th>
<td>Tue, 04 Jun 2013 22:08:07 -0700</td>
</tr>
<tr>
<th nowrap="nowrap" valign="BASELINE" align="RIGHT">From: </th>
<td>Kirk R. Smith <a class="moz-txt-link-rfc2396E" href="mailto:krksmith@berkeley.edu"><krksmith@berkeley.edu></a></td>
</tr>
<tr>
<th nowrap="nowrap" valign="BASELINE" align="RIGHT">To: </th>
<td>Paul Anderson <a class="moz-txt-link-rfc2396E" href="mailto:psanders@ilstu.edu"><psanders@ilstu.edu></a></td>
</tr>
</tbody>
</table>
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<br>
<pre>At 09:31 PM 6/4/2013, you wrote:
>Dear Kirk,
>
>Your reply (below) is quite useful, and I hope the Stovers on the
>Listserv will read it. And it leads to further questions:
>
>1. Did I understand correctly? You say that HALF of a single
>cigarette per day (directly inhaled) is equal to the PM 2.5 inhaled
>(as "secondary" smoke in the kitchen) by a cook or child who is in a
>typically poorly enclosed "smoky kitchen" with a 3-stone fire . WOW!!
Cannot say exactly for the child, but yes for an adult. Worse thing
you can do is stick burning stuff in your mouth. Next worse is have
a bunch of it burning in your house (HAP: household air
pollution). Next is having someone else sticking in their mouth near
you. And not even so great having it burning somewhere in your
city. See the post on the CNN website:
<a class="moz-txt-link-freetext" href="http://globalpublicsquare.blogs.cnn.com/2013/01/18/tackling-the-worlds-forgotten-killer/">http://globalpublicsquare.blogs.cnn.com/2013/01/18/tackling-the-worlds-forgotten-killer/</a>
>2. And that a
>>typical open wood cookfire produces about 400 cigarettes an hour
>>worth of PM2.5
>(that I assume can also be inside a poorly enclosed cooking
>space). If a person takes 12 minutes to smoke one cigarette, that
>is 5 per hour for one person. So the 3-stone fire creates a smoky
>environment that is the equivalent of 80 persons smoking 5
>cigarettes per hour in an enclosed space. That helps explain the
>smoke billowing out under the eaves and through the door and cracks
>of many "kitchens" with 3-stone fires.
>(Did I express that correctly?)
yes
>I was in one of these kitchens 10 days ago in Uganda, and I sat low
>to the floor because higher up was so horrible. But being in such a
>setting even for many hours would only equal the equivalent of half
>of one cigarette that is inhaled per day. BUT THAT CONSTITUTES THE
>FOURTH WORSE HEALTH HAZARD FOR PEOPLE IN THE LEAST DEVELOPED COUNTRIES.
Yes, the exposure response relationship is highly non-linear. For
example, the heart disease risk for a secondhand tobacco smoker is
maybe 1.8 while the risk for active smoking is perhaps 2.5. And yet
the active smoker experiences hundreds of times more dose (say 60
versus 20,000 ug/m3 equivalent). HAP is in between (at around
300). Thus, burden from smoking, while bigger, is not orders of
magnitude so - 6 million premature deaths annually compared to 3-4
for HAP. See the attached commentary.
>3. And from the above, can we say the following:
>Improved biomass-burning cookstoves need to be soooo clean burning
>that the air in the kitchen should cleaner than that of a kitchen in
>which only 10? or 5? (or 2? or how many?) cigarettes are smoked per hour.
>Of course the number will vary depending on the openness or
>enclosed-ness of the kitchen.
Yes, at least a reliable 95% reduction in emissions over open fires,
which actually are not well characterized. To be reliably 95%, it
probably means 99% reduction in controlled testing. A cigarette
emits 12 mg, roughly. Probably need to limit to no more than a few
per day (equivalent) to meet the WHO IT-1 guideline of 35 ug/m3 mean,
depending on household size and ventilation rate. We are developing
these relationships more formally in the WHO Indoor AIr Quality
Guidelines Expert Group -- also using a monte carlo approach to
express results as probabilities. In its second draft and under
review at present. Plan is that the WHO guidelines will be
incorporated into the final ISO standards down the road.
Stay tuned.
>Another way of saying the same thing: When the current technology
>/equipment for testing stove emissions is in use (such as for 75
>minutes, which is 30 minutes to boil plus 45 minutes for simmer),
>what would be the equivalent of passive smoke from how many
>cigarettes that would equal the Tier 0, 1, 2, 3, and Tier 4
>levels? Think of this a one person smoking (exhaling smoke) under
>the hood of the equipment.
>
>I think that these comparisons can be useful, but only when we have
>some numbers will we be able to see if the info is useful.
>
>Paul
>
>Paul S. Anderson, PhD aka "Dr TLUD"
>Email: <a class="moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a> Skype: paultlud Phone: +1-309-452-7072
>Website: <a class="moz-txt-link-abbreviated" href="http://www.drtlud.com">www.drtlud.com</a>
>
>On 6/4/2013 5:40 PM, Kirk R. Smith wrote:
>>
>>
>>At 02:30 PM 6/4/2013, you wrote:
>>
>>>Thank you to Kirk Smith for his reply (below for all Stove
>>>Listmembers to read).
>>>
>>>I think someone told me that <2.5 PM cannot be seen. But if
>>>there is a lot of it, is it visibly detectable (like the haze of a
>>>smoky room, or is that just the larger particles that we are seeing?)
>>
>>yes, but the coefficient of haze measured in outdoor settings is
>>highly correlated with PM2.5, but only if adjusted for humidity.
>>
>>
>>>Related question: For a small child besides it mother in a smoky
>>>cooking shack, cooking "typically" 2 - 3 times per day, what is
>>>the "equivalent" as expressed in cigarettes smoked per
>>>day? And can that be expressed as equivalent of SECONDARY
>>>smoke from being in a room with smokers in it (but that becomes
>>>confused because of room size and number of smokers in it)?
>>
>>Not an answerable question since small children do not smoke (who
>>knows how much they would breath in if they did). For an adult,
>>the levels are a about half a cigarette or so equivalent in daily
>>dose (PM2.5 inhaled), depending of course on how polluted the house is.
>>In terms of secondhand tobacco smoke, a typical open wood cookfire
>>produces about 400 cigarettes an hour worth of PM2.5. More in
>>terms of some other pollutants, for example BAP.
>>
>>All this is laid out in some detail in my book "Biofuels, Air
>>Pollution, and Health" (Plenum, 1987)/k
>>
>>
>>>I am trying to visualize this as a mother/cook smoking cigarettes,
>>>and as a baby or a 2-year old child smoking cigarettes (an
>>>unnatural but powerful visual image).
>>>
>>>Paul
>>>
>>>Paul S. Anderson, PhD aka "Dr TLUD"
>>>Email: <a class="moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a> Skype: paultlud Phone: +1-309-452-7072
>>>Website: <a class="moz-txt-link-abbreviated" href="http://www.drtlud.com">www.drtlud.com</a>
>>>
>>>On 6/4/2013 9:15 AM, Kirk R. Smith wrote:
>>>>Quick responses below
>>>>
>>>>At 06:27 AM 6/4/2013, Paul Anderson wrote:
>>>>
>>>>>Stovers,
>>>>>
>>>>>Please tell me or direct me to an explanation of the impact of
>>>>>the PM that is BETWEEN PM 2.5 and PM 10.
>>>>>
>>>>>I believe that the experts say that under 2.5 is the bad stuff
>>>>>for respiratory health, and that over 10 is not sufficiently
>>>>>important even to be measured.
>>>>
>>>>Yes, material over PM10 generally is caught in the upper
>>>>respiratory system (nose, etc) and does not penetrate the body
>>>>sufficiently to be a health hazard. May be a nuisance, of
>>>>course. Major reviews of health impacts, however, show that the
>>>>fine fraction (less than 2.5) is the best single indicator for
>>>>health, but that the coarse fraction (between 2.5-10) also shows
>>>>effects. Thus, no agency has abandoned PM10 regs, but most are
>>>>moving to add PM2.5 regs as well.
>>>>Issue for measurements right at the combustion source is that
>>>>nearly all is PM2.5.
>>>>
>>>>
>>>>>Is PM size 10 to 25 (twenty five) ( 50 or 100) "visible"?
>>>>>Detectable to the nose or eyes?
>>>>
>>>>yes, which is a reason that perception is not a great indicator of hazard
>>>>
>>>>
>>>>>What causes cataracts?
>>>>
>>>>not known for sure, but probably from internal, not external
>>>>exposure to combustion-related pollutants in any case. Chemical
>>>>carried to the eye through the blood. Eye is well protected
>>>>externally. Need to think of PM2.5 as the best indicator of a
>>>>mixture, not that itself causes all effects. Like "tar" for
>>>>cigarettes, which is essentially PM2.5
>>>>
>>>>
>>>>>How important is the PM larger than 2.5?
>>>>
>>>>See above.
>>>>
>>>>
>>>>>Please forward this inquiry to the stove-medical people who are
>>>>>not readers of this Listserv.
>>>>>
>>>>>Paul
>>>>>
>>>>>--
>>>>>Paul S. Anderson, PhD aka "Dr TLUD"
>>>>>Email: <a class="moz-txt-link-abbreviated" href="mailto:psanders@ilstu.edu">psanders@ilstu.edu</a> Skype: paultlud Phone: +1-309-452-7072
>>>>>Website: <a class="moz-txt-link-abbreviated" href="http://www.drtlud.com">www.drtlud.com</a>
>
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