[Stoves] Between PM 2.5 and PM 10

[Paul Anderson]

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?)

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)?

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:  psanders at ilstu.edu   Skype: paultlud  Phone: +1-309-452-7072
Website:  www.drtlud.com

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:  psanders at ilstu.edu   Skype: paultlud  Phone: +1-309-452-7072
>> Website:  www.drtlud.com
>>
>