Health and Climate Implications of Emissions from Small Scale Industries in Mexico. Rufus Edwards

Transcription

1 Health and Climate Implications of Emissions from Small Scale Industries in Mexico Rufus Edwards

2 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.

3 Black carbon BC radiative forcing at the top-of-the atmosphere is as much as 34-60% of the current radiative forcing due to CO 2 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. Tami Bond 2007 The figure shows ratios between organic matter (OM) and BC; for direct forcing, about a 10:1 ratio is climate neutral.

4 Charcoal Combustion related biomass consumption National charcoal 15% domestic 80% brick 5% Charcoal Pottery Brick Purepecha region brick 22% copper 0% pottery 15% bread 1% domestic 61%

5 Charcoal

6 Global warming compounds produced by biomass combustion Under ideal circumstances carbon based fuels produce only water and CO 2 Carbon fuel CO 2 + H 2 O Circumstances are rarely ideal however Carbon fuel CO 2 + H 2 O inefficient CO + CH combustion 4 + NMHC particulate In addition combustion temperature results in nitrous oxides (N 2 0) + matter

7 Kiln measurements

8

9 Brick kiln CO 2 /(CO 2 +CO) (proxy for combustion efficiency) Fugitive Mean combustion efficiency of ~85% Plume :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 Time Fugitive CO2/(CO2+CO) CO2 CO Fugitive 15% of combusted carbon is being emitted as methane, black carbon, and other products of incomplete combustion. Plume Plume CO 2, CO (ppm)

10 NCE and Emissions Charcoal kiln 1 was more efficient due to air entry

11 Kiln Weight (Kg) Pottery Pottery 2 Firing: 175 Glazing: 101 TOTAL 276 Pottery 3 Firing: 378 Glazing: 389 TOTAL 767 Copper 2 22 Copper 3 85 Copper 4 10 Brick bricks Brick bricks Brick bricks Wood consumption Kiln Weight (Kg) Charcoal (kg) Moisture content Species Charcoal % 95% Q. castanea 5% Q laeta Charcoal % 100% Q. castanea For comparison, the moisture content of air dried fire wood is around 20-25%.

12 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

13 Reduced cell viability 120% 100% µg/ml 25 µg/ml 50 µg/ml 100 Cell viability (%) 80% 60% 40% 20% 0% Diesel Urban dust Brick Charcoal Copper Pottery Higher doses trigger defensive reaction through antioxidant defense mechanisms (Andre Nel)

14 Reduction in ROS production 120% 100% µg/ml 25 µg/ml 50 µg/ml 100 RLU/control RLU 80% 60% 40% 20% 0% Brick Charcoal Copper Pottery

15 NO production NO production/# macrophages (µm) 4E-05 3E-05 2E-05 1E-05 Media µg/ml 25 µg/ml 50 µg/ml 100 0E+00 Control Urban Dust Brick Charcoal Copper Pottery

16 Cell viability per particle mass vs PIC 35.0% 30.0% Charcoal 25.0% Brick PIC 20.0% 15.0% 10.0% Copper Pottery y = 0.51x r 2 = % 0.0% 0.0% 20.0% 40.0% 60.0% 80.0% 100.0% % Cell Viability per particle mass

17 NO production per particle mass vs 35.0% 30.0% 25.0% PIC Charcoal Brick PIC 20.0% Pottery y = -1.2E04x r 2 = % 10.0% Copper 5.0% 0.0% 0.0E E E E E E E-05 NO production per viable cell (µm) Consistent with the cell viability - Peroxynitrite formed from NO attacks cell membranes leading to cell death

18 Reduction is ROS production per viable cell and PIC 35.0% 30.0% 25.0% 20.0% Brick Charcoal Pottery y = -0.29x r 2 = 0.7 PIC 15.0% 10.0% 5.0% Copper 0.0% 0.0% 20.0% 40.0% 60.0% 80.0% 100.0% 120.0% ROS reduction per viable cell

19 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

20 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