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Fine Atmospheric Particles: Do we need to worry about them??. Almost all combustion leads to the formation of fine particles. Mastery of Fire. 400,000 years ago in Europe 100,000 years ago in Africa M. N. Cohne, 1977. Ultimately we learned how to use fire to clear land for crops.

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Mastery of fire

Mastery of Fire particles

400,000 years ago in Europe

100,000 years ago in Africa

M. N. Cohne, 1977



In China 2000 years ago the Loess crops

Plateau was the cradle of ancient Chinese

civilization. Deforestation due to:

Firewood collection Charcoal making

Creation of farm land

Brick making

resulted in a much drier and less

productive climate



When fire was brought inside the home very large smoke exposures resulted:

  • These exposures are often much higher in the developing world than in the industrialized world

  • Women tend to spend more time around unvented fires than men



Exposures are indoors as well as outdoors picture by kirk smith india early 1980s
Exposures are indoors as well as outdoors much higher exposures to indoor fires than males (Kirk Smith, 1983)Picture by Kirk Smith, India, early 1980s


After a few hours
After a few hours much higher exposures to indoor fires than males (Kirk Smith, 1983)


Acute respiratory infections 6 month in rural nepal infants vs time near stove m r panday 1984
Acute Respiratory Infections/6 month in Rural Nepal Infants vs. time Near Stove (M. R. Panday, 1984)




Comparative particulate concentrations in m g m 3
Comparative Near Stove ParticulateConcentrations in mg/m3

  • U.S. Standard (PM2.5) 65

  • Sydney (1996) ~25

  • Traffic- Denmark 60

  • London Smog (1952) 4,500

  • Muese, Belgium 12,500

  • Indian village 1,000(Indoors ) 56,000

  • Malaysia (1997, PM2.5) 800

  • Thailand (1998, PM2.5) 300


Combustion forms a host of toxics that are associated with soot particles
Combustion forms a host of toxics that are associated with soot particles

  • Polynuclear aromatic hydrocarbons (PAH)

  • Chlorinated dioxins and furans

  • Aldehydes and carbonyl compounds


Polynuclear Aromatic Hydrocarbons (PAH) soot particles

as a class of compounds are considered potential carcinogens


Combustion formation of pah
Combustion Formation of PAH soot particles

Badger and Spotswood 1960


Combustion formation of dioxins from polychlorinated phenol
Combustion Formation of Dioxins from Polychlorinated phenol soot particles

O

H

C

l

x

.

OH

Flame

C

l

x

.

O

O

H

+

Polychlorinated

Phenol

C

l

y

O

+ OH

O

C

l

y

O

C

l

x

O

H

C

l

x

C

l

y

Chlorinated dibenzo dioxin

Shaub & Tsang, ES&T 1983.



Many of these compounds exist as a free gas and on particles this influences
Many of these compounds exist as a free gas and on particles. This influences:

  • how they will be deposited on the earth's surface

  • the types of chemical reactions they can undergo

  • the route by which they enter the food chain and are sorbed or deposited in the lungs


Gas particle partitioning
Gas Particle Partitioning particles. This influences:

toxic gas

particle


Langmuirian adsorption 1918
Langmuirian Adsorption (1918) particles. This influences:

gas

surface

  •  = fraction of total sites occupied

  • Rateon= kon (Pg) (1- );

  • Rateoff= koff;

  • kon/koff= Keq


Langmuirian isotherm
Langmuirian Isotherm particles. This influences:

  • if Keq Cgas<< 1; = Keq Cgas


Junge 1977
Junge (1977) particles. This influences:

  •  = jcj /(Po + jcj)

    • = fraction in aerosol phase

    • Po= sat. vapor pressure of the pure compound

    • j = conc. of aerosol surface (cm2/cm3)

    • cj =const, bBET, moles of sites/cm2,temp

    • cj=RTNse(Qi-Ql)/RT


anthracene particles. This influences:

A vapor pressure calculation for the liquid vapor for anthracene

Tb= 198 + S DTb ; C14H18

anthracene has10, =CH- , carbons and each carbon = 26.73oK/carbon

It also has 4, =C< at 31.01OK/carbon

Tb = 198 + 267.3 + 124.04 = 589;

Published boiling point is = 613K

At 298K, lnPoL = -12.76; p = 2.87 x10-6atm = 0.0022 torr


Percent in the aerosol phase at different aerosol concentrations 25 o c
Percent in the Aerosol Phase at Different Aerosol Concentrations (25oC)

Phen Pyrene BaP

8x10-4 6x10-5 2x10-7

10g/m3 0.2 2 91

100g/m3 3.1 23 99

500g/m3 18 68 100

rural= 0.5m, high urban 0.35m, Bangkok =0.25m


Yamasaki et al 1982
Yamasaki et al.(1982) Concentrations (25

  • Langmuirian adsorption

  • Assumes total # sites  TSP (particle conc)

  • log Ky = -a(1/T)+ b


Yamasaki 1982

filter Concentrations (25

BaA

log Ky

PUF

1/Tx1000

Yamasaki (1982)

  • Collects Hi-vol filters+PUF

  • Analyzes for PAHs


Yamasaki s relationship
Yamasaki’s relationship Concentrations (25

  • This gives a log Ky = -a(1/T)+ bwhich is compound specific

  • Ideally from the regression values of a and b, one can estimate the partitioning of a given compound in any atmosphere at a given temp. and TSP



Application of this theory Concentrations (25


A number of years ago we conducted two wood smoke experiments in our Teflon film chambers to evaluate the stability of 9,10 anthraquinone.

The average chamber temperature for one experiment was 20oC and the other was 38oC. A third experiment was conducted at 30oC, but only filters were analyzed. Data from these experiments are given below.


Unc 25m 3 teflon film chambers
UNC 25m experiments in our Teflon film chambers to evaluate the stability of 3Teflon Film Chambers


Three years later it became very important to know the PUF ( experiments in our Teflon film chambers to evaluate the stability of gas phase) and particle phase distribution of anthraquinone at the 30oC experiment.

It costs, however, 10,000 USD to re-run experiments.


9,10-anthraquinone data in the gas (PUF) and particle (filter) phases

Temp gas (PUF) particle (filter) TSP ng/m3 ng/m3 mg/m3

38oC 228 105 0.512 20oC 38 381 0.366 30oC ? 440 0.832

So what do we do??

lnKy = -a(1/T)+ bTemp is in Kelven


PAH (filter) phasesGas

PAHpart

lnKy = -a(1/T)+ b


Log k p log p o l const k p part gasxtsp

log K (filter) phasesp = -log Po(L) + const. Kp= part/(gasxTSP)

slope = -1

log Kp

  • Ambient data of Pankow and Bidleman

    • PAHs, alkanes

    • chlorinated organics

log Po(L)


For liquid like particles partitioning coefficient k p is
For liquid like particles partitioning coefficient, K (filter) phasesp, is:

  • Kip = 760 RT fomx10-6/{iPLtorrig MWavg}

    log Kip= - log iPo(L) +C -log ig

  • C= log [fom (7.501 RT)/ (106Mwom)]

    • fom = fraction of particle organic mass

    • Mwom = avg. Mw of om in the particle


Calculating activity coefs i g
Calculating Activity Coefs, (filter) phasesig

  • RT lnigom= iV[(omdd - idd)2 +ib(omdp - idp)2+ ib(omdh - idh)2] + RT [ln(iV/Vom) +1- iV/Vom]

  • Vom is the molar volume of the mix

  • ds are solubility parameters

  • dd = S Fd,j / iV


Partitioning uptake by the lungs
Partitioning & uptake by the lungs (filter) phases

  • Nicotine (Pankow’s group)


Uptake by the lungs nicotine
Uptake by the lungs (Nicotine) (filter) phases

  • Under normal circumstances Nicotine can exist as a neutral “free base” or as a protonated mono or di-acid and will appear predominately in the particle phase.

  • Typically cigarette smoke has pH values ³3 and much of the nicotine exists in the acidified form on particles.


Nicotine
Nicotine (filter) phases

  • The acidified form can not partition between the gas and particle phase.

  • If ammonia is added to the tobacco smoke, “as a flavor enhancement”, the pH increases moving the equilibrium on the particles from the mono-acid to the neutral form.


Impact and “advantages” of ammonia “flavor enhancement” on partitioning

  • In the neutral form nicotine can partition to the gas phase.

  • neutral nicotine can then be readily absorbed by the wet surface of the inner lung (Pankow’s group)

  • loss of nicotine to the lungs “pulls” more nicotine off the particles


What are aerosols
What are aerosols? enhancement” on partitioning

  • Aerosols are simply airborne particles

  • They can be solids or liquids or both

  • They can be generated from some of the following sources:


What are aerosols1
What are aerosols? enhancement” on partitioning

  • Aerosols are simply airborne particles

  • They can be solids or liquids or both

  • They can be generated from some of the following sources: 1. combustion emissions 2. atmospheric reactions 3. re-entrainment



What are some of the terms used to describe aerosols1
What are some of the terms used to describe aerosols? enhancement” on partitioning

  • Diameters are usually used to describe aerosol sizes, but aerosols have different shapes.


Often particles are sized by their aerodynamic diameter
Often particles are sized by their aerodynamic diameter enhancement” on partitioning

  • The aerodynamic diameter of a particle is defined as the diameter of an equivalent spherical particle (of unit density) which has the same settling velocity.

  • It is possible to calculate the settling velocity of a spherical particle with a density =1


  • Density = mass/volume enhancement” on partitioning DensityH20 = 1gram/cm3= 1

  • Terminal Settling velocity (Vs ) is the rate that a particle falls due to gravity




A Log normal distribution is often applied to the size data by plotting the logs of the particles size vs frequency

The log of the geometric mean is

log diameter


The log normal distribution
The log normal distribution by plotting the logs of the particles size vs frequency


Aerodynamic diameters of some particles
Aerodynamic diameters of some particles by plotting the logs of the particles size vs frequency

  • tobacco smoke 0.25 mm

  • ammonium chloride 0.1

  • flour dust 15- 20

  • fogs 1- 5

  • pollens 15- 70

  • talc 10

  • photochemical aerosols 0.01-1


Aerosol exposures
Aerosol exposures by plotting the logs of the particles size vs frequency

  • Indoors

  • Outdoors

  • Cars

  • Work place


Aerosol exposures1
Aerosol exposures by plotting the logs of the particles size vs frequency

  • Indoors (90% of our time)

    • ventilation systems

    • mechanically re-entrain particles (dust mites)

    • cooking


Indoor activities generate particles by plotting the logs of the particles size vs frequency


Activities that generate aerosols in kamens home
Activities that generate aerosols in Kamens home by plotting the logs of the particles size vs frequency


Cooking stir fried vegetables kamens house 1987 eaa data
Cooking stir-fried vegetables: Kamens house, 1987, EAA data by plotting the logs of the particles size vs frequency


Vacuuming in kamens house
Vacuuming in Kamens House by plotting the logs of the particles size vs frequency


Kamens house at night
Kamens house at night by plotting the logs of the particles size vs frequency


How do particle sizes distribute in the atmosphere
How do particle sizes distribute in the atmosphere?? by plotting the logs of the particles size vs frequency


How do particle sizes distribute in the atmosphere1
How do particle sizes distribute in the atmosphere?? by plotting the logs of the particles size vs frequency

.3-.8 um

4-10 um


Particle samplers often collect particles smaller than a given size
Particle samplers often collect particles smaller than a given size

  • PM10 is defined as particles with diameters < 10 mm.

  • It is measured in units of mg/m3 , typically by pulling air through filters.

  • PM2.5 is defined as particles with diameters < 2.5 mm



Why is this important given size???


Why is this important given size???

Naso-oro-pharyngo-

Tracheo-bronchial

Alveolar


Where do particles deposit
Where do particles deposit?? given size

  • Large particles deposit in the Naso-oro-pharyngo- region

  • Very fine particles (< 0.01 mm) deposit in the Tracheo-bronchial

  • About 15-20% of the particles between 0.1 and 1 mm deposit in the Alveolar region



Aerodynamic diameters of some particles1
Aerodynamic diameters of some particles given size

  • tobacco smoke 0.25 mm

  • ammonium chloride 0.1

  • flour dust 15- 20

  • fogs 1- 5

  • pollens 15- 70

  • talc 10

  • photochemical aerosols 0.01-1

  • Car exhaust 0.1- 0.3



Killer Particles and Morbidity


Recent particle health studies
Recent Particle Health Studies and Morbidity

  • Dockery et al., N. Eng .J. Med, vol 329, p1753, 1993)

  • looked at 6 American cities with different annual PM2.5 concentrations

  • From 1974 to 1990, they followed 8111 males and females.

  • Subjects were 25-74 years old


Mortality rates were estimated from
Mortality rates were estimated from: and Morbidity

  • Survival times (date of death minus the start date for that person in the study)

  • Raw mortality rates are computed, for each city, which are the number of deaths/year/100,000 people

  • These were adjusted for smoking, education, body mass index, and other risk factors


Mortality vs particle exposure

1.3 and Morbidity

1.2

mortality ratio

1.1

1.0

10 20 30 40

2.5 mm particle conc. in mg/m3

Mortality vs. particle exposure

On a mass basis urban fine particles may be more toxic than cigarette smoke


Another study by pope et al am j crit care med vol 151 p669 1995
Another Study by and Morbidity(Pope et al., Am J. Crit. Care Med., vol 151, p669, 1995)

  • looked at 151 cities with different annual PM2.5 concentrations in 1980

  • 552,138 mostly white adults


Deaths/10000 and Morbidity

2.5 mm particle conc. in mg/m3


  • Used a Cox and Morbiditymultiple regression analysis proportional hazards model

  • Fleming, T.R. and D.P Harrington Counting Processes and Survival Analysis. John Wiley, New York,1991

  • SAS Technical Report P-217; SAS/STAT Software: The PHREG Procedure. Version 6; SAS Institute, Cary NC,USA


Using their model they could look at the risks associated with:

  • age

  • sex

  • race

  • cigarette smoking

  • passive smoke exposure

  • body mass

  • alcohol intake

  • education

  • occupational exposure


Adjusted Mortality Risk Ratios for exposure to 24.5 with:mg/m3 fine particles

Smokers

  • women 1.16

  • men 1.18

    NEVER SMOKED

  • women 1.22

  • men 1.14


The Pope et al. study concludes that: with:

  • Risks for increased pollution exposure were the same for smokers and non smokers

  • The association between pollution and mortality was not very sensitive to: occupation, education, body mass, alcohol, and temperature

  • occupational differences between men and women did not matter


There are other studies of this type with:

  • Typically they find the strongest relationship with fine particles and sulfate aerosols

  • There is usually an association with all particles < 10 or 15 mm,but it is not as strong as with fine particles

  • Less of a relationship with aerosol acidity and almost none for O3CO, NOx


The latest interpretations do not find the strong relationship that was observed back in 1993, but still report a significant particle exposure and mortality relationship (this is what is in your book chapter, Figure 2-21)


In a particle study in bangkok 1998
In A Particle Study relationship that was observed back in 1993, but still report a significant particle exposure and mortality relationship (this is what is in your book chapter, Figure 2-21) in Bangkok, 1998

  • health effects were associated with airborne particles

  • They measured PM10

  • Particle concentrations in Bangkok tend to be higher than in other cities around the world


  • The results suggest that at current PM relationship that was observed back in 1993, but still report a significant particle exposure and mortality relationship (this is what is in your book chapter, Figure 2-21)10 concentrations in Bangkok, there are between 1,000 and 2,000 premature deaths each year

  • These deaths are attributable to short-term exposures to outdoor airborne particulate matter

  • This represents about 5% to 10% of all recorded deaths in Bangkok





These types of studies environments, the average outdoor particulate matter during the winter months still increased their symptoms by about

  • suggest a 1-2% increase in the mortality rate for every 10 ug/m3 of fine particulate matter (Schwartz et al, 1996)

  • Contributed to the US EPA setting a PM2.5 ambient particle standard at65 mg/m3 for 24 hours, not to exceed the 3rd highest value in 3 years; sampling ~1 time per week



Samet et al. at UNC have recently exposed human airway epithelial cells to residual oil fly ash (ROFA) particles

  • cells secreted prostaglandins

  • Prostaglandins are a class of potent inflammatory mediators which play a role in inflammatory, immune and functional responses in the lung


Human volunteers had inert fe 2 o 3 particles introduced into their lungs lay et al 1995
Human volunteers had inert Fe epithelial 2O3 particles introduced into their lungs (Lay et al, 1995)

  • Produced a subclinical inflammatory response in the first 24-48 hours

  • Influx of macrophages and neutrophils onto the alveolar spaces as assessed by bronchoalveolar lavage

  • Protein releases suggests alveolar epithelial damage



Drop in u s air pollution linked to longer life spans

Americans are living longer because the air they breathe is getting cleaner, a new study suggests. The average drop in pollution seen across 51 metropolitan areas between 1980 and 2000 appears to have added nearly five more months to people's lives, according to a study published Wednesday in The New England Journal of Medicine.

Drop in U.S. air pollution linked to longer life-spans

Americans are living longer because the air they breathe is getting cleaner, a new study suggests. The average drop in pollution seen across 51 metropolitan areas between 1980 and 2000 appears to have added nearly five more months to people's lives, according to a study published Wednesday in The New England Journal of Medicine (Pope et. al, 2008.)


Many other factors can boost life expectancy, such as increases in income and education and reductions in smoking prevalence, so the researchers used statistical techniques to control for these and other relevant factors.

After this adjustment, they found that the effect of air pollution reduction remained; for every 10 microgram per cubic meter decrease in fine-particulate air pollution, life expectancies rose by about seven months. Pollution levels averaged about 21 micrograms per cubic meter in 1979-1983 and had fallen to an average of 14 micrograms per cubic meter by 1999-2000.


  • ChiangMai, Thailand increases in income and education and reductions in smoking prevalence, so the researchers used statistical techniques to control for these and other relevant factors.

  • Do we see the same kinds of particle health responses in northern Thai Populations??


  • Currently, there are only a few studies which relate increases in income and education and reductions in smoking prevalence, so the researchers used statistical techniques to control for these and other relevant factors.PM2.5 on a daily basis to mortality and morbidity





In 1998 the us epa provided cmu with particle samplers
IN 1998, The US EPA provided CMU with particle samplers particle concentrations

  • 8 saturation samplers with batteries;

  • more than 1000 Teflon filters; these can be used to obtain particle mass

  • Flow calibration gear

  • 7- small samplers for personal monitoring


PM particle concentrations2.5 or PM10 inlet

  • Saturation sampler for PM2.5 or PM10

47mm filter holder

pump

rotameter

on/off digital timer

lunch

Battery

18cm


pump

Battery

~18cm


So how do these samplers work
So how do these samplers work?? particle concentrations


Sizing particles with impactors
Sizing particles with impactors particle concentrations

  • Impactors bring aerosols through a jet

  • The particles and air speed up as they go through the small orifice


Sizing particles with impactors1
Sizing particles with impactors particle concentrations

  • Impactors bring aerosols through a jetdisk

  • A disk or plate is place down stream of the jet


Sizing particles with impactors2
Sizing particles with impactors particle concentrations

  • Impactors bring aerosols through a jet

  • The disk has grease or oil on the surface


Sizing particles with impactors3
Sizing particles with impactors particle concentrations

  • Depending on the speed through the jet, large particles will hit the disk, while small particles follow the air around the disk


Sizing particles with impactors4
Sizing particles with impactors particle concentrations

Filter

  • A filter is placed under the disk to collect particles that do not hit the disk





Located samplers
Located samplers week

  • residential area in the city- PM2.5

  • 5th roof top- urban sample not influenced by different sources- PM2.5 & PM10

  • high population density area (down town market?)- PM2.5

  • relatively clean air- PM2.5



We located 6 samplers on the 2nd floor outside porch of Nui’s house and sampled for 24 hours on March 1, 1998


We located 6 samplers on 2nd floor outside porch of Nui’s house and sampled for 24 hours on March 1, 1998


average 121 ug/m3 house and sampled for 24 hours on March 1, 1998

2 x % std 8.4%


Four different sampling locations were selected for monitoring pm2 5
Four different sampling locations were selected for monitoring PM2.5

  • Down town area (Nui’s house)

  • Residential area (Dr. Usanee’s house)

  • General city exposure (outside 5th floor of medical school)

  • Background (2nd floor -Galae )


ChiangMai monitoring PM2.5



ChiangMai compare


When we sampled for more than one year
When we sampled for more than one year compare

winter

winter

Summer

Summer



PM 2.5 level number of firesmg/m3

His + of TA100/plate

Mutagenicity vs. PM 2.5

Mar 98

Apr

May

Jun

Jul

Aug

Sep

PM 2.5 levels and air-borne mutagenicity in Chiang Mai ambient air at different monitoring sites in the same month. Bar graph = PM 2.5 level at

= site 1, = site 2, = site 3, = site 4.

Line = mutagenicity at

= site 1, = site 2, = site 3, = site 4, spontaneous revertants have been substracted already.


ChiangMai number of fires


If the downtown site, for example, “experienced” a slightly higher exposure to diesel exhaust which, is much more mutagenic than wood smoke, the PM levels would appear similar, but the mutagenicity would be influenced by the diesel particles and appear higher.


A high prevalence of asthma in children living in Chiang Mai has been reported.

At the present time, however, it is difficult without further study to know if open burning is exacerbating the asthma problem in Chiang Mai.

It would seem prudent, given the high fine particle concentrations, to curtail open burning as much as possible. Future studies should also attempt to identify compounds in Chiang Mai air that are potentially toxic to human health so that these may be used as bench marks for future control strategies.


Recommendations
Recommendations? has been reported.

  • 2 stroke motor cycles account for half of the motor vehicles and can emit more than 10 times the amount that gasoline cars do. We need to go to 4 stroke engines

  • Replace small diesel pick-up trucks gasoline engine pick-up trucks-maintenance off all vehicles

  • Control open burning!!


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