Intervention Strategies for Woodstove Homes

Transcription

1 Intervention Strategies for Woodstove Homes Tony Ward, Ph.D. The University of Montana Center for Environmental Health Sciences June 16, 2011

2 Mexico City, Mexico

3 Beijing, China

4 Los Angeles, California

5 Source:

6 Ambient PM

7 EPA 24-Hour PM 2.5 Nonattainment Areas *As of Aug 2010 National Ambient Air Quality Standard (NAAQS): Annual, 15 μg/m 3 ; 24-hr, 35 μg/m 3.

8 Woodstoves

9 Chemical Mass Balance (CMB) PM Source 2.5 Apportionment Computer modeling to determine what the sources of PM 2.5 are in the airsheds. 1) Collect PM 2.5 air samples. 2) Analyze the air samples for chemical species. 3) Use an EPA computer model (CMB) to apportion the sources.

10 Air Samplers

11 Sources of Hamilton PM 2.5 Winter 2007/2008 Street Sand 1.0% SO4 4.4% NH4NO3 17.4% Residential Wood Combustion 75.8% Unexplained 1.5% Average PM 2.5 : 11.0 μg/m 3 11/2/07 3/1/08

12 Sources of Butte PM 2.5 Winter 2007/2008 Unexplained 3.2% Street Sand 2.6% SO4 3.2% Diesel 0.2% NH4NO3 10.2% Residential Wood Combustion 77.0% Autos 3.6% Average PM 2.5 : 13.5 μg/m 3 11/8/07 3/1/08

13 Sources of Helena PM 2.5 Winter 2007/2008 Cement Kiln 0.5% Unexplained 3.7% Street Sand 2.9% Diesel 0.3% SO4 4.9% NH4NO3 18.9% RWC 66.4% Autos 2.4% Average PM 2.5 : 9.0 μg/m 3 11/2/07 3/1/08

14 Sources of Kalispell PM 2.5 Winter 2008/2009 Unknown 2.3% Street Sand 1.8% Sulfate 3.8% Ammonium Nitrate 15.5% Diesel 6.9% Residential Wood Combustion 68.8% Automobiles 0.8% Average PM 2.5 : 10.1 μg/m 3 11/2/08 2/24/09 Average PM 2.5 : 9.0 μg/m 3 11/2/07 3/1/08

15 Fairbanks State Building CMB Results (November 11, 2008 April 7, 2009)

16 Fairbanks - North Pole CMB Results (January 25, 2009 April 7, 2009)

17 Woodstoves In the rural Northern Rocky Mountains of western Montana, PM 2.5 is the major ambient air pollution issue (especially during the winter months). The majority of the wintertime PM 2.5 comes from woodstoves (56 77%). Ward T, Lange T. The impact of wood smoke on ambient PM2.5 in northern Rocky Mountain valley communities. Environ Pollut Mar;158(3):723-9.

18 Woodstove Changeouts Woodstove changeouts are becoming a common tool targeting ambient woodsmoke PM 2.5. A good example is Libby, Montana.

19 Woodstove Changeout Old stove g smoke/hr EPA-certified stove 2-5 g smoke/hr

20 PM 2.5 Nonattainment Areas (2003) NAAQS: Annual, 15 μg/m 3 ; 24-hr was 65 μg/m 3.

21 PM Seasonal 2.5 Trends Courthouse Annex-Libby AIRS Code POC 5 (ROUTINE) 10/16/01 12/10/01 2/3/02 3/30/02 5/24/02 7/18/02 7/7/07 9/11/02 11/5/02 12/30/02 2/23/03 4/19/03 6/13/03 8/7/03 10/1/03 11/25/03 1/19/04 3/14/04 5/8/04 7/2/04 8/26/04 10/20/04 12/14/04 2/7/05 4/3/05 5/28/05 7/22/05 9/15/05 11/9/05 1/3/06 2/27/06 4/23/06 6/17/06 8/11/06 10/5/06 11/29/06 1/23/07 3/19/07 5/13/07 8/31/07 Date PM2.5 Concentration (µg/m³)

22 Winter 2003/2004 Libby, Montana Sources of PM 2.5 Street Sand 0% SO4 2% NH4NO3 5% Autos 7% Diesel 4% Residential Wood Combustion 82% Avg PM 2.5 : 28.2 ug/m 3 Ward, T.J., Rinehart, L.R., and Lange, T., The 2003/2004 Libby, Montana PM2.5 source apportionment research study, Aerosol Science and Technology, 40:

23 Temperature Inversions

24 Woodstoves

25 Libby Woodstove Changeout Program Funding provided by Montana DEQ, EPA, and HPBA.

26 Libby Woodstove Changeout Program Nearly 1,200 old woodstoves were changed out, modified, or surrendered between 2005 and 2008.

27 Wood Stove Change-out Program: A Natural Experiment Conduct prospective multi-year study to assess changes in woodsmoke PM 2.5 and impact on health of school children following the intervention. 1. Monitor changes in ambient PM Monitor changes in school indoor PM Evaluate the change in residential indoor PM 2.5 following a changeout. 4. Track changes in reporting of symptoms and illness-related absences among students.

28 PM 2.5 in Libby and NAAQS

29 PM 2.5 in Libby and NAAQS

30 Key Finding - Libby A large woodstove changeout can be effective in reducing ambient levels of PM 2.5. Bergauff, M.A., Ward, T.J., Noonan, C.W., and Palmer C.P The effect of a woodstove changeout on ambient levels of PM 2.5 and chemical tracers for woodsmoke in Libby, Montana. Atmospheric Environment, 43, Ward, T.J., Palmer, C.P., Houck, J.E., Navidi, W.C., Geinitz, S., and Noonan, C.W., A community woodstove changeout and impact on ambient concentrations of polycyclic aromatic hydrocarbons. Environmental Science & Technology, 43(14), Ward, T. J., Palmer, C. P., and Noonan, C. W., 2010, PM 2.5 source apportionment following a large woodstove changeout program in Libby, Montana. Journal of the Air and Waste Management Association, 60:

31 What about the impact of a woodstove changeout on indoor levels of PM 2.5? 1) Libby, Montana. 2) Nez Perce Woodstove Changeout Program.

32 Exposure Assessment Within Homes

33 15:22 Libby 2006/2007 Residential PM 2.5 Program PM 2.5 Mass - Home 4A Before Changeout Concentration (ug/m 3 ) :53 06: Start Sampling: 14:00 End Sampling: 14:00 Avg = Timeμg/m 3

34 2006/2007 Libby Residential PM 2.5 Sampling Program PM 2.5 Sampling focused on 20 homes containing woodstoves. 24-hour PM 2.5 sampling Pre-changeout period (Oct/Nov 2006). Post-changeout (Dec 2006 Feb 2007). The goal of the program was to evaluate the impact of this intervention on indoor air quality within the home.

35 140 Libby PM 2.5 Mass Results Pre and Post Stove Changeout Pre Avg PM2.5 Post Avg PM2.5 Home 1 Home 3 Home 5 Home 6 Home 7 Home 8 Home 9 Home 10 Home 11 Home 12 Home 13 Home 14 Home 15 Home 17 Home 18 Home 20 PM2.5 Concentration (ug/m 3 ) Pre-changeout avg PM 2.5 : 53.4 μg/m 3 Post-changeout avg PM 2.5 : 15.0 μg/m 3

36 PM Maximum 2.5 Spikes Pre and Post Stove Changeout Pre- PM2.5 Post- PM2.5 PM2.5 Concentration (ug/m 3 ) Home 1 Home 3 Home 5 Home 6 Home 7 Home 8 Home 9 Home 10 Home 11 Home 12 Home 13 Home 14 Home 15 Home 17 Home 18 Home 20 Pre-changeout spike avg: 434 μg/m 3 Post-changeout spike avg: 103 μg/m 3

37 Libby Residential Program, cont. Did the stove changeout work over time? Ward, T.J., Palmer, C., Bergauff, M., Hooper, K., and Noonan, C., Results of a residential indoor PM 2.5 sampling program before and after a woodstove changeout, Indoor Air, 18:

38 Followup PM Indoor 2.5 Study Air sampling was conducted in a total of 26 woodstove homes. Five phases: Phase 1 = pre stove change, 2006/2007 winter. Phase 2 = post change, same winter. Phase 3 = post change, 2 nd 2007/2008 winter. Phase 4 = post change, 3 rd 2007/2008 winter. Phase 5 = post change, 4 th 2008/2009 winter.

39 Libby Residential Study (winters of 2006/ /2009 (3 winters) Pre-changeout avg PM 2.5 : 63.2 µg/m 3 Post-changeout avg PM 2.5 : 28.9 µg/m 3

40 Results of Multi-Winter Residential Study Overall reductions following the wood stove changeout were observed in 16 of 21 homes. High variability was observed for post-changeout sampling within some homes, but 14 of the 21 homes still had lower PM 2.5 concentrations for all post-changeout sampling compared to prechangeout PM 2.5 concentrations.

41 Nez Perce Woodstove Changeout Program

42 Nez Perce Woodstove Changeout Conducted during the winters of 2006/2007, 2007/2008, and 2008/2009. Kamiah and Lapwai, Idaho on the Nez Perce Reservation. 16 homes.

43 Nez Perce Woodstove Changeout PM 2.5 Mass Results PM2.5 Concentration (ug/m 3 ) Home Avg PM2.5 Pre (ug/m3) Avg PM2.5 Post (ug/m3) ~278% PM 2.5 increase Pre-changeout avg PM 2.5 : 43.1 μg/m 3 Post-changeout avg PM 2.5 : μg/m 3

44 Importance of Training PM2.5 Concentration (ug/m 3 ) Home 2 Home 6 Home 11 Home Pre Post 1 Post 2 Sampling Event PM 2.5 Mass (µg/m 3 ) Measured in Homes Following Outreach/Education. Ward, T.J., Boulafentis, J., Simpson, J., Hester, C., Moliga, T., Warden, K., and Noonan, C.W., Results of the Nez Perce woodstove changeout program, Science of the Total Environment, 409,

45 Woodstove Changeouts Effective in reducing ambient PM 2.5. Expensive (~$ $4500). Learning curve. Results can be variable for indoor air.

46 Another Indoor Intervention - Filtration Units -

47 Overall Averages for the 3M Study PM 2.5 ug/m With a 3M Filter Without a 3M Filter Samples Averaged Overall Averages Without Outliers Avg ~50% PM 2.5 Reduction in Woodstove Homes

48 A Randomized Trial for Indoor Smoke (ARTIS) 5-year, NIEHS funded study. The Primary Aim of this study is to assess the impact on quality of life among asthmatic children following interventions that reduce in-home woodsmoke PM exposures.

49 Study Design: Randomized Trial Group 1 (n=36) Recruitment Randomization Group 2 (n=36) Group 3 (n=36) Winter #1: Baselines Exposure and Health Outcomes Measures X Tx1: EPA- Certified Woodstove Tx2: Active Air Filter Units In two rooms Tx3: Inactive Air Filter Units (Placebo) Winter #2: Post-intervention Exposure and Health Outcomes Measures

50 Health Outcome Measures PAQoL Peak flow Symptoms eno Biol. samples EBC Urine Dr. Curtis Noonan

51 Indoor Air Sampling

52 ARTIS Preliminary Results

53 Summary Woodstoves are a significant source of PM 2.5 in both ambient and indoor environments. Woodstove changeouts can be effective in reducing ambient wintertime PM 2.5 results are more variable indoors. Filtration units are consistently effective in improving indoor air in homes with woodstoves.

54 Acknowledgements Funding NIH Centers of Biomedical Research Excellence (p20- RR017670). Health Effects Institute (#4743-RFA04-4/06-4). NIEHS (1R01ES ; 3R01ES S1) Montana Department of Environmental Quality (DEQ). Alaska Department of Environmental Conservation (DEC, Barbara Trost and Jim Connor). EPA Region 10 (Mary Manous). Nez Perce ERWM (Johna Boulafentis and Julie Simpson). The 3M Corporation. Toyota USA Foundation.

55 Thank you. Tony Ward (406)