Health and Climate Implications of Emissions from Small Scale

Industries in MexicoRufus Edwards

Small scale industries• Climate and air quality implications of emissions from small scale solid fuel

use are being assessed with woefully incomplete knowledge. • Rural small scale industries are practically uncharacterized, and we don’t

know a) how many there are, b) their emissions, or c) what fraction of biomass use they constitute. Even if we did know numbers and locations, application of industrialized country emission factors, such as those from the USEPA’s AP-42 database, would almost certainly result in considerable errors in climate and pollution transport models, and would not be appropriate for particulate emissions.

• Little information is available on the toxicity of aerosol emissions and how these compare to diesel or Urban PM

• In Asia, models systematically underestimate atmospheric CO concentrations and black carbon concentrations. Recent work has pointed to small-scale combustion, including cooking stoves and small-scale industry, as a reason for these underestimates.

• Emissions from these sectors have major global health effects in directly impacted communities and through background ozone which affects global health.

Black carbon

Tami Bond 2007

BC radiative forcing at the top-of-the atmosphere is as much as 34-60% of the current radiative forcing due to CO2

Rural small scale industries and residential sectors are estimated to be 34% of the total

Global emissions of black carbon (year 2000), and the ratio of primary OM to BC for each category.

The figure shows ratios between organic matter (OM) and BC; for direct forcing, about a 10:1 ratio is “climate neutral.”

Combustion related biomass consumption

CharcoalCharcoal Pottery

Purepecha regionbrick 22%copper 0%pottery 15%bread 1%domestic 61%

Nationalcharcoal 15%domestic 80%brick 5%

Brick

Charcoal

Global warming compounds produced by biomass combustion

• Under ideal circumstances carbon based fuels produce only water and CO2

• Circumstances are rarely ideal however

• In addition combustion temperature results in nitrous oxides (N20)

OHCOCarbonfuel 22 +⇒

OHCOCarbonfuel 22 +⇒

mattereparticulatNMHCCHCO

combustiontinefficien

+++⇓

4

Kiln measurements

Brick kiln

0

1000

2000

3000

4000

5000

6000

7000

0.6

0.65

0.7

0.75

0.8

0.85

0.9

0.95

1

12:43:12 12:50:24 12:57:36 13:04:48 13:12:00 13:19:12 13:26:24 13:33:36 13:40:48 13:48:00

CO

2, C

O (p

pm)

CO

2/(C

O2+

CO

) (p

roxy

for c

ombu

stio

n ef

ficie

ncy)

Time

CO2/(CO2+CO)CO2CO

Fugitive

Plume

Fugitive

Plume

Fugitive

Plume

Mean combustion efficiency of ~85%

15% of combusted carbon is being emitted as methane, black carbon, and other products of incomplete combustion.

NCE and Emissions

Charcoal kiln 1 was more efficient due to air entry

Wood consumptionKiln Weight (Kg)

Pottery 1 269Pottery 2 Firing: 175

Glazing: 101TOTAL 276

Pottery 3 Firing: 378Glazing: 389TOTAL 767

Copper 2 22Copper 3 85Copper 4 10Brick 1 6808 25000 bricksBrick 2 8430 30000 bricksBrick 3 4113 12000 bricks

Kiln Weight (Kg) Charcoal (kg) Moisture content SpeciesCharcoal 1 3047 518 40% 95% Q. castanea 5% Q laetaCharcoal 2 7303 1292 41% 100% Q. castanea For comparison, the moisture content of air dried fire wood is around 20-25%.

Invitro Assays• Live/Dead Viability/Cytotoxicity Assay, by Neutral red

assay with absorbance Spectrometry. Neutral red picked up by live cells and stored in vescicles

• Superoxide Production During Respiratory Burst Activity following stimulation with PMA (phorbol 12-myristate 13-acetate) by lucigenin-amplified chemiluminescence. Macrophages generate ROS in order to kill some types of bacteria that they engulf by phagocytosis. In vivo and in vitro models show suppression of defense against infection after exposure to particulate matter.

• Griess Reagent System, Nitric Oxide (NO) Determination by Absorbance Spectrometry. NO production has been repeatedly shown to be a major antimicrobial mechanism of macrophages. Increased NO production indicates an activation of immune inflammatory response.

• Doses approximately equivalent to a cumulative 5 day work week exposure in Los Angeles – less in rural Mexico

Reduced cell viability

0%

20%

40%

60%

80%

100%

120%

Diesel Urban dust Brick Charcoal Copper Pottery

Cel

l via

bilit

y (%

)

µg/mL 25µg/mL 50µg/mL 100

Higher doses trigger defensive reaction through antioxidant defense mechanisms (Andre Nel)

Reduction in ROS production

0%

20%

40%

60%

80%

100%

120%

Brick Charcoal Copper Pottery

RLU

/con

trol

RLU

µg/mL 25µg/mL 50µg/mL 100

NO production

0E+00

1E-05

2E-05

3E-05

4E-05

Control UrbanDust

Brick Charcoal Copper Pottery

NO

pro

duct

ion/

# m

acro

phag

es (

µM)

Mediaµg/mL 25µg/mL 50µg/mL 100

Cell viability per particle mass vs PIC

y = 0.51x - 0.16r2 = 0.96

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

35.0%

0.0% 20.0% 40.0% 60.0% 80.0% 100.0%% Cell Viability per particle mass

PIC

Charcoal

Brick

Pottery

Copper

y = -1.2E04x + 0.46r2 = 0.75

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

35.0%

0.0E+00 5.0E-06 1.0E-05 1.5E-05 2.0E-05 2.5E-05 3.0E-05NO production per viable cell (µM)

PIC

NO production per particle mass vs PIC

Charcoal

Brick

Pottery

Copper

Consistent with the cell viability - Peroxynitrite formed from NO attacks cell membranes leading to cell death

y = -0.29x + 0.43r2 = 0.7

0.0%

5.0%

10.0%

15.0%

20.0%

25.0%

30.0%

35.0%

0.0% 20.0% 40.0% 60.0% 80.0% 100.0% 120.0%

PIC

ROS reduction per viable cell

Reduction is ROS production per viable cell and PIC

Charcoal

Brick

Pottery

Copper

Conclusions•Combustion in Small scale industries is largely inefficient and contributes substantially to regional PIC emissions.•Particle emissions impact macrophages which are a primary defense mechanism of the body. Decrease free radical production which impairs defense against infection. Increase NO production indicating an activation of immune inflammatory response•Toxicity of particles varies for different small scale industries both on a particle mass basis and an overall emission basis. Currently we are not sure of the drivers of the differential toxicity•Health implications and emissions of greenhouse species should not be generalized across types

Acknowledgements

•UC Mexus•UCI Environment Institute•Dr. Omar Maser•Dr Adrian Ghilardi•Dr Loyda Mendez•Dr Mike Kleinman•Dr Michael Johnson•Alejandro del Valle Reynoso•Melissa Benitez